WO2013157014A1 - Group iii-nitride semiconducting material and a method of manufacturing the same - Google Patents

Group iii-nitride semiconducting material and a method of manufacturing the same Download PDF

Info

Publication number
WO2013157014A1
WO2013157014A1 PCT/IN2012/000287 IN2012000287W WO2013157014A1 WO 2013157014 A1 WO2013157014 A1 WO 2013157014A1 IN 2012000287 W IN2012000287 W IN 2012000287W WO 2013157014 A1 WO2013157014 A1 WO 2013157014A1
Authority
WO
WIPO (PCT)
Prior art keywords
nitride
nucleation
group ill
buffer layer
polar
Prior art date
Application number
PCT/IN2012/000287
Other languages
French (fr)
Inventor
Priti Gupta
A. Azizur RAHMAN
Maheshwar Ramchandra GOKHALE
Lokeshwar BANDHU
Mandar Madhukar DESHMUKH
Arnab Bhattacharya
Original Assignee
Tata Institute Of Fundamental Research
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tata Institute Of Fundamental Research filed Critical Tata Institute Of Fundamental Research
Priority to PCT/IN2012/000287 priority Critical patent/WO2013157014A1/en
Publication of WO2013157014A1 publication Critical patent/WO2013157014A1/en

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02436—Intermediate layers between substrates and deposited layers
    • H01L21/02439—Materials
    • H01L21/02441—Group 14 semiconducting materials
    • H01L21/02444—Carbon, e.g. diamond-like carbon
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02436—Intermediate layers between substrates and deposited layers
    • H01L21/02439—Materials
    • H01L21/02455—Group 13/15 materials
    • H01L21/02458—Nitrides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02436—Intermediate layers between substrates and deposited layers
    • H01L21/02494—Structure
    • H01L21/02496—Layer structure
    • H01L21/02502—Layer structure consisting of two layers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02518—Deposited layers
    • H01L21/02521—Materials
    • H01L21/02538—Group 13/15 materials
    • H01L21/0254—Nitrides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02518—Deposited layers
    • H01L21/02609—Crystal orientation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02612—Formation types
    • H01L21/02617—Deposition types
    • H01L21/0262—Reduction or decomposition of gaseous compounds, e.g. CVD
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02367—Substrates
    • H01L21/0237—Materials
    • H01L21/02373—Group 14 semiconducting materials
    • H01L21/02376—Carbon, e.g. diamond-like carbon

Definitions

  • TITLE GROUP III-NITRIDE SEMICONDUCTING MATERIAL AND A METHOD OF MANUFACTURING THE SAME
  • the present invention relates to Group Ill-nitride semiconducting materials comprising a graphene based layer having thereon at least one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group III- nitride semiconducting film selected from alloy family of (AI,Ga,In,B) N on said nitride nucleation/buffer layer, in orientations selected from polar, non-polar and semi-polar with or without a suitable underlying substrate.
  • group III- nitride semiconducting film selected from alloy family of (AI,Ga,In,B) N on said nitride nucleation/buffer layer, in orientations selected from polar, non-polar and semi-polar with or without a suitable underlying substrate.
  • the said Group Ill-nitride semiconducting film in the semiconducting material of the present invention comprises one or more layers of dissimilar compositions of the (Al, Ga, In, B) N alloy family selected from at least one or more of: binary GaN, AIN, InN compound semiconductors; ternary alloys of AIGaN, AIInN, InGaN ; or quaternary alloys of AIGalnN and the like, in said film.
  • the present invention more particularly relates to planar, free-standing said Group Ill-nitride semiconducting material comprising graphene as the selective intermediate layer having deposited thereon at least one Group Ill-nitride semiconducting film in semi-polar orientations such as (10-11), (11-22), (10-13), wherein said graphene as the selective intermediate layer having at least one nitride nucleation/ buffer layer allows the growth of said Group III nitride semiconducting film in said semi-polar orientations.
  • the present invention relates to an improved method of manufacturing said planar, group Ill-nitride semiconducting material scalable to large area preferably in semi-polar orientation, and more preferably, also relates to a method of providing free standing layers/ membrane of said group-Ill nitride semiconducting material that is advantageously transferable to a wide variety of substrates selected from glass or flexible plastic substrates and adapted for the fabrication of various optoelectronic devices including LEDs,' lasers, transistors.
  • Gallium nitride and related ternary and quaternary alloys are well-established as important materials for light emitting diodes and lasers in the UV/visible region.
  • the most stable crystal structure of group III nitrides is the hexagonal wurtzite form.
  • most single crystal thin films of the group III nitrides are grown on the basal plane, i.e. the c-plane or (0001) oriented plane. In this orientation, the alternating layers of Gallium and Nitrogen atoms lead to a spontaneous polarization that induces an internal electric field.
  • most nitrides are grown on sapphire, in which lattice mismatch results in strain, which further leads to piezoelectric polarization.
  • Polarization-related issues are a major cause of concern in the performance of these devices, especially in the widely used crystal orientation-the standard basal plane (0001) of the wurtzite crystal structure.
  • crystal orientation-the standard basal plane (0001) of the wurtzite crystal structure Recent experimental evidence suggests that the use of "semi-polar" planes (wurtzite crystal planes such as ⁇ 11-22 ⁇ , ⁇ 10-11 ⁇ , ⁇ 10-13 ⁇ etc.) are advantageous for optoelectronic devices, and such semi-polar layers have been used to demonstrate the best green LEDs and lasers.
  • US Patents including US 7,687,293, US 7,575,947, US 7,790,584 and US 7,704,324 disclose methods for growing a semi-polar nitride semiconductor thin film on a substrate, all of which require either a complicated multi-step etch, or re-growth processes, or achieve the semi-polar surface only in certain regions of the wafer, or require miscut /(Disoriented substrates.
  • Graphene has been a material of contemporary research interest as it can serve as a transparent conducting electrode for use in various optoelectronic devices.
  • Ill-Nitride materials such as GaN on graphene has not received much attention possibly due to the chemical inertness of the graphene surface.
  • a recent publication by Chung et al. claims that GaN nucleation does not occur on the basal plane of pristine graphene, and some GaN islands grow on roughened graphene surfaces subjected to Oxygen-plasma treatment. They say that even the typical two-temperature growth process using a low-temperature GaN buffer layer does not improve the film properties. Hence they use zinc oxide as an intermediate layer for GaN growth.
  • group Ill-nitride semiconducting (Al, Ga, In, B)N material to enable fabrication of wide range of optoelectronic devices including LEDs, lasers, transistors involving said free-standing layers/ membrane and a method to achieve the same involving the steps of lifting off the group Ill-nitride material from the substrate on which it is deposited so as to transfer it to another substrate.
  • a Group III- nitride semiconducting material comprising of graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on said nitride nucleation /buffer layer.
  • nitride nucleation/buffer layer adapted for conformal coverage of entire graphene based layer and thereon providing for atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on sa jd nitride nucleation /buffer layer, that enabled the provision of the much desired single phase semiconducting material and preferably even in semi-polar orientations.
  • the single phase semiconducting material of the present invention which involves a graphene based layer is also advantageous in that the same is easily scalable to large area and also advantageously transferable to a wide variety of substrates selected from glass or flexible plastic substrates adapted as free standing layers/ membrane of said Group Ill-nitride semiconducting material favouring fabrication of various optoelectronic devices.
  • said Group Ill-nitride semiconducting material wherein said group Ill-nitride semiconducting films of (Al, Ga, In, B) N comprise at least one or more layers of dissimilar compositions within the alloy family of (AI,Ga,In,B)N.
  • Group Ill-nitride semiconducting material wherein graphene based group Ill-nitride semiconducting film is planar with one or more orientations selected from polar, non- polar and semi-polar and selected from the group comprising of GaN, AIN, InN, AIGaN, AIInN, InGaN and AIGalnN.
  • said Group Ill-nitride semiconducting material wherein said graphene based group Ill-nitride semiconducting films comprise one or more layers of dissimilar compositions of the (Al, Ga, In, B) N alloy family selected from at least one or more of: GaN, AIN, InN alloys; ternary alloys of AIGaN, AIInN, InGaN; or quaternary alloys of AIGalnN and the like, in said film.
  • Group Ill-nitride semiconducting material wherein said graphene based group Ill-nitride semiconducting films comprise free standing graphene based films with one or more orientations selected from polar, non-polar and semi-polar preferably with semi-polar orientations selected from (10-11), (11-22), (10-13) as a single phase material.
  • said Group Ill-nitride semiconducting material wherein said graphene based group Ill-nitride semiconducting free standing films shaped and configured for variety of applications.
  • suitable substrates include rigid substrates preferably including glass or transparent conducting oxide (TCO) coated glass, and/or flexible substrates preferably including plastics or metal foils.
  • TCO transparent conducting oxide
  • said Group Ill-nitride semiconducting material wherein said nitride nucleation/buffer layer adapted for conformal coverage of entire graphene surface comprise is an alloy selected from combinations of alloy family (Al, In, Ga)N preferably AIN.
  • said Group III- nitride semiconducting material comprising said graphene based group Ill-nitride semiconducting films on suitable substrates including sapphire, patterned sapphire, silicon, silicon oxide /dioxide coated silicon, silicon nitride coated silicon, silicon carbide and glass.
  • said graphene based group Ill-nitride semiconducting films adapted as free standing films on releasable sacrificial substrate layers including silicon oxide/dioxide, silicon nitride, spin-on-glass, polyimides.
  • said graphene Group Ill-nitride semiconducting films scalable to a large area from 10s to about 100s of cm 2 adapted for various optoelectronic devices.
  • a Group Ill-nitride semiconducting material comprising of graphene based layer having thereon at least one AIN nucleation /buffer layer having conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (Al, Ga, In, B)N on said nitride nucleation /buffer layer with semi-polar orientations selected from (10-11), (11-22), (10-13).
  • a method of manufacture of Group Ill-nitride semiconducting material comprising a) providing a graphene based layer on a substrate;
  • a method of manufacture of Group Ill-nitride semiconducting material comprising a) providing a graphene based layer on a substrate;
  • the single phase semiconducting material of the present invention could avoid the limitations of achieving graphene based semiconducting materials with planar large area films by the above control of process parameters whereby even in the absence of specially miscut or mis-oriented sapphire or spinel substrates allows attainment of said Group Ill-nitride semiconducting material as a single phase material of high material quality with preferred semi-polar orientations that is advantageously both scalable to large area and also transferable to a wide variety of substrates adapted as free standing layers/ membrane of planar large-area films of said Group Ill-nitride semiconductors.
  • said nitride nucleation /buffer layer is grown on said graphene layer such as to achieve said conformai coverage on entire graphene based layer followed by growing thereon said nitride nucleation /buffer layer the said nitride semiconducting film involving a semiconductor deposition system and following one or more of techniques selected from metal organic chemical vapor deposition ( OCVD), metal organic vapour phase epitaxy (OVPE), solid or gas source molecular beam epitaxy (MBE), and hydride vapor phase epitaxy (HVPE). More preferably, said nitride semiconducting film is grown in one or more orientations selected from polar, non-polar and semi-polar. According to another aspect of the present invention said step (b) of providing a nucieation /buffer layer having conformal coverage on entire graphene based layer comprises the steps of
  • said step of providing AIN as nucieation /buffer layer comprises growing said nucieation /buffer layer involving precursors for nucieation involving low pressure in the range of 20 to 100 Torr following stepwise growth preferably involving either (A) two stage growth comprising (i) following a first stage growth for thickness in the range of 10 to 20 nm at temperature in the range of 700 to 800°C followed by (ii) second stage growth for thickness in the range of 25 to 40 nm at temperature in the range of 1000 to 1100 °C or (B) three stage growth (i) following a first stage growth for thickness in the range of 10 to 20 nm at temperature in the range of 600 to 700 °C (ii) second stage growth for thickness in the range of 10 to 20 nm at temperature in the range of 800 to 950 °C and (Mi) third stage growth for thickness in the range of 20 to 30 nm at temperature in the range of 1000 to 1100 °C .
  • said step (c) of providing thereon said nitride nucieation /buffer layer, the group III nitride semiconducting film comprises the steps of providing required metalorganic and hydride precursors in the pressure ranging from 20 to 760 Torr, temperature ranging from 530 to 1100 °C, depending on the particular Ill-Nitride film deposited.
  • said AIN as nucleation /buffer layer is grown in said semipolar orientation (10-11) involving precursors for nucleation and growth involving trimethylaluminium, ammonia and hydrogen carrier gas in the preferred temperature range of 600 to 1100 °C preferably about 1000 °C and pressure in the range of 20 to 100 Torr, preferably 50 Torr and with selective V/III ratio in the range of 2500 to 10000 preferably above 3500.
  • nitride nucleation /buffer layer comprises growing the GaN film involving trimethylgallium, ammonia and hydrogen carrier gas, at 50 to 200 Torr preferably 50 Torr reactor pressure at temperature 1000 to 1100°C preferably of 1040°C to thereby obtain semi-polar oriented said GaN group III nitride semiconducting film as a single phase material.
  • AIN nitride nucleation /buffer layer preferably AIGaN as the group III nitride semiconducting film
  • providing thereon said AIN nitride nucleation /buffer layer, preferably AIGaN as the group III nitride semiconducting film comprises growing said Group Ill-nitride film involving selective precursor involving trimethylgallium, trimethylaluminium and ammonia and hydrogen carrier gas, at 50 to 100 Torr preferably 50 Torr reactor pressure at temperature 1000 to 1100°C preferably of 1040°C to thereby obtain semi-polar oriented said group III nitride semiconducting film comprising AIGaN semi-polar (10-11) layer adapted as a single phase material.
  • providing thereon said AIN nitride nucleation /buffer layer, InN or InGaN or as the group III nitride semiconducting film comprises growing the Group Ill-nitride film involving selective precursor involving trimethylindium, trimethylgallium, and ammonia and nitrogen carrier gas, at 200 to 500 Torr reactor pressure at temperature 530 to 800°C to thereby obtain semi-polar oriented said group III nitride semiconducting film comprising InN semi-polar (10-11) layer or InGaN semi-polar (10-11) layer adapted as a single phase material.
  • said substrate is selected from a group comprising of Sapphire, patterned Sapphire, Silicon, Silicon Oxide/Dioxide coated Silicon, Silicon Nitride coated Silicon, Silicon Carbide and Glass also comprising releasable sacrificial substrate layers including silicon oxide/dioxide, silicon nitride, spin-on-glass, polyimides.
  • said substrate is surface conditioned prior to deposition of said nitride semiconducting film by exposure to oxygen plasma after which thermal cleaning of the substrate is preferably achieved by heating under hydrogen flow just prior to growth in the semiconductor deposition system.
  • nucleation /buffer layer having conformal coverage, atleast one group Ill-nitride semiconducting film selected from alloy family of (Al, Ga, In, B)N to obtain therefrom graphene based group III nitride semiconducting films of desired thickness; and d) removing the sacrificial layer to thereby obtain free standing Group Ill-nitride semiconducting material.
  • a method comprising obtaining free standing graphene based group III nitride semiconducting films wherein said sacrificial substrate is selected from silicon oxide/ dioxide, silicon nitride, spin-on-glass, polyimides which is removed preferably by chemical etching of the said sacrificial layer, e.g. the silicon dioxide layer below said graphene layer is etched using HF/buffered HF.
  • an optoelectronic device comprising Group Ill-nitride semiconducting material comprising of graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on said nitride nucleation /buffer layer with or without a suitable substrate.
  • Group Ill-nitride semiconducting material comprising of graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on said nitride nucleation /buffer layer with or without a suitable substrate.
  • a semiconducting material adapted for facilitating epitaxial growth of semiconducting films as epilayer thereon comprising of graphene based layer and atleast one nitride nucleation /buffer layer comprising an alloy selected from combinations of alloy family (Al, In, Ga)N having conformal coverage of entire graphene surface with or without a suitable substrate.
  • Fig. 1 depicts scanning electron microscope image showing conformal coverage of entire surface with AIN buffer layer on graphene
  • Fig. 3 depicts X-ray diffraction (XRD) profiles of the ⁇ -2 ⁇ scan for on-axis reflections for AIN layers grown on graphene at (a) different substrate temperatures and (b) different V/III ratios;
  • XRD X-ray diffraction
  • Fig. 4 depicts X-ray diffraction (XRD) profiles of the ⁇ -2 ⁇ scan for on-axis reflections showing AIN buffer layer and GaN semi-polar layer (10-11) grown on graphene;
  • Fig. 5 depicts room temperature photoluminescence emission spectra from the semi- polar (10-11) oriented GaN and AIGaN layers showing high material quality;
  • Fig. 6 depicts X-ray diffraction (XRD) profiles of the ⁇ -2 ⁇ scan for on-axis reflections showing patterns of GaN on AIN on graphene grown under different conditions showing mixed phases at low temperature
  • Fig. 7 depicts X-ray diffraction (XRD) profiles of the ⁇ -2 ⁇ scan for on-axis reflections of AIGaN alloy samples of varying aluminium content
  • Fig. 8(a) depicts a process of lift off of free standing GaN layer, after etching the underlying silicon dioxide layer in buffered HF (Fig.8 b), the nitride layer floats up on to the surface (Fig. 8 c), Fig. 8 (d) depicts free-standing GaN layer transferred to a glass slide, and Fig. 8 (e) is a x-ray diffraction pattern of the free-standing GaN showing a semi-polar orientation (10-11). Fig 8 (f) shows room temperature photoluminescence from the free-standing GaN layer, pointing to the high material quality.
  • the present invention provides for Group Ill-nitride semiconducting material comprising graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and at least one group Ill-nitride semiconducting film selected from alloy family of (Al, Ga, In, B)N on said nitride nucleation /buffer layer, in orientations selected from polar, non-polar and semi-polar with or without a suitable substrate.
  • the said Group Ill- nitride semiconducting film of the semiconducting material of the present invention comprises one or more layers of dissimilar compositions of the (Al, Ga, In, B) N alloy family selected from at least one or more of: GaN, AIN, InN alloys; ternary alloys of AIGaN, AIInN, InGaN; or quaternary alloys of AIGalnN and the like.
  • the present invention provides for planar free standing semiconducting material scalable to large area and advantageously transferable to a wide variety of substrates selected from glass or flexible plastic substrates thereby favouring fabrication of various optoelectronic devices including LEDs, lasers, transistors wherein said III- nitride semiconducting film preferably involves semi-polar orientation such as (10-11), (11-22), (10-13).
  • the present invention relates to a method of growing planar group Ill-nitride semiconducting film (AI,Ga,In,B)N on a substrate comprising steps of:
  • the nitride semiconducting film grown by the present method can be deposited more of orientations selected from polar, non-polar and semi-polar orientations. By appropriate choice of growth conditions semi-polar orientations such as (10-11), (11- 22), (10-13) etc. can be obtained.
  • the planar group III nitride semiconducting film that is grown may contain one or more layers of dissimilar compositions of the (AI,Ga,In,B)N alloy family.
  • films which can be grown by the present method can be one or more of GaN, AIN, InN; ternary alloys like AIGaN, AIInN, InGaN; or quaternary alloys like AIGalnN and the like.
  • the planar group III nitride semiconducting film can be grown using one or more techniques selected from metal organic chemical vapor deposition (MOCVD), metalorganic vapour phase epitaxy (MOVPE), solid and gas source molecular beam epitaxy (MBE), or hydride vapor phase epitaxy (HVPE).
  • MOCVD metal organic chemical vapor deposition
  • MOVPE metalorganic vapour phase epitaxy
  • MBE solid and gas source molecular beam epitaxy
  • HVPE hydride vapor phase epitaxy
  • the group Ill-nitride semiconducting film is grown in a semi-polar orientation which is selected from (10-11), (10-13) and (11-22).
  • semi-polar group Ill-nitride semiconducting film can be grown on substrates such as Silicon, Sapphire, Silicon Carbide, or Silicon-dioxide/Silicon-nitride coated Silicon substrates using a graphene interlayer.
  • substrates such as Silicon, Sapphire, Silicon Carbide, or Silicon-dioxide/Silicon-nitride coated Silicon substrates using a graphene interlayer.
  • the present method does not require specially miscut or mis-oriented sapphire or spinel substrates.
  • Large area graphene layers used in the present invention can be synthesized using standard Chemical Vapor Deposition (CVD) techniques as disclosed in the literature, for example, through deposition by cracking of methane at high temperature on copper (or nickel) foils, followed by etching and lift-off.
  • CVD Chemical Vapor Deposition
  • Graphene Synthesis by CVD on Copper Substrates The 2009 NNIN REU Research Accomplishments, p. 71 to 74 and Matthew O'Brien et al, "CVD Synthesis and Characterization of Graphene Thin Films", Army Research Laboratory, 2010, p. 1 to 15, http: //www.arl.army.mil/arlreports/2010/ARL-TR-5047.pdf.
  • nickel see for example, K-S. Kim, et al, Nature 457, 706-710 (2009).
  • surface conditioning of the graphene layer prior to deposition of nitride layer was done by exposure to oxygen plasma.
  • the wafer was loaded into an MOVPE reactor and heated under hydrogen flow and thermally cleaned, typically at 1040°C for 5 min before cooling down for deposition of the nucleation or buffer layer.
  • the nitride nucleation or buffer layer used was AIN, which was grown conformally as detailed below on the graphene layer (Fig. 1), hence permitting the growth of smooth layers of GaN on top of it (Fig 2a), whereas direct deposition of GaN on the graphene layer (at 1040 °C 50 Torr) results in isolated island growth (Fig. 2b).
  • the AIN nucleation layer was grown at a low reactor pressure, for example, 50 Torr, and either as a two step growth - for example, low temperature nucleation step of 15 nm at 600°C, followed by a high temperature grown layer 35 nm at 1040°C, or as a 3-step growth with a low temperature nucleation step of 15 nm at 600°C, followed by 15 nm growth at 900°C, and a high temperature grown buffer layer 35 nm at 1040°C.
  • a low reactor pressure for example, 50 Torr
  • the reactor temperature was further ramped to an appropriate temperature for growth of desired group Ill-nitride semiconducting epilayer.
  • the reactor temperature ranged from 1040°C for GaN to 530°C for InN.
  • Example III Under this example, in accordance with the present invention, the desired group III- nitride semiconducting epilayer was grown on top of an AIN buffer layer by admitting the appropriate metalorganic and hydride precursors at a specific pressure, temperature, V/III ratio, and growth rate to favour a preferential surface orientation of the epilayer. It was noted that typically high temperature and low pressure conditions favored the growth of semi-polar oriented layers while low temperature and high pressure conditions lead to mixed phases with polar and semi-polar oriented domains.
  • Example IV Under this example, AIN layers were grown using trimethylaluminium and ammonia and hydrogen carrier gas, at growth temperatures ranging from 800°C to 1100°C and V/III ratios from 500 to 5000.
  • Fig. 3 (a) shows the X-ray diffraction (XRD) of the ⁇ -2 ⁇ scan for on-axis reflections for a series of AIN layers grown at different growth temperatures in the range 900 to 1040°C keeping other parameters fixed. From the accompanying figure it can been seen at lower temperatures mixed phases are obtained, as the temperature increases the intensity of the (0002) peak drops, and reached a minimum at an optimum temperature of 1000°C.
  • Fig. 3 shows the X-ray diffraction (XRD) of the ⁇ -2 ⁇ scan for on-axis reflections for a series of AIN layers grown at different growth temperatures in the range 900 to 1040°C keeping other parameters fixed. From the accompanying figure it can been seen at lower temperatures mixed phases are obtained, as the temperature increases the intensity of the (0002)
  • 3(b) shows a series of AIN layers growth at different V/III ratios from 500 to 4500 keeping other parameters fixed. From the figure it can be seen that for growth at low V/III ratio other parasitic phases such as the (0002), (10-12) and (11-20) are seen. These phases reduce on increasing the V/III ratio, and almost single phase (10-11) semipolar AIN is obtained at V/III ratios above 3500.
  • GaN and AIGaN layers were grown using trimethylgallium, trimethylaluminium and ammonia and hydrogen carrier gas, growth at 1040°C and 50 Torr reactor pressure leading to layers with a preferential (10-11) orientation (Fig. 4)
  • Fig. 4 shows the X-ray diffraction (XRD) profile of the ⁇ -2 ⁇ scan for on-axis reflections showing AIN buffer layer, GaN semi-polar (10-11) layer and AIGaN semi-polar (lO-l l)layer grown on graphene. A single phase material was thus obtained.
  • Fig. 5 shows the room temperature photoluminescence from these GaN and AIGaN layers pointing to the high quality of the material.
  • Fig. 6 shows the X-ray diffraction (XRD) profile of the ⁇ -2 ⁇ scan for on-axis reflections showing patterns of GaN on AIN on graphene grown under different conditions showing mixed phases at low temperature.
  • XRD X-ray diffraction
  • InN and In-containing alloys were grown in a similar manner as described herein, but by using nitrogen carrier gas instead of hydrogen. After a group III nitride semiconducting layer of a desired thickness was grown, the supply of reagents was switched off and the reactor cooled to room temperature and the sample removed.
  • planar group III nitride films obtained by the present method are found to be advantageously of a large area, limited only by the size of the graphene layer transferred onto the substrate. Since CVD graphene can be grown over large areas (10s to 100s of cm 2 ), semi-polar nitride films of large area can thus be obtained by the method of the present invention.
  • Example VI
  • the graphene layer was transferred to a silicon dioxide or silicon nitride coated substrate (wafer).
  • the silicon dioxide/nitride served as a sacrificial layer in a process for the fabrication of free standing semiconductor layers.
  • the method of the present invention provides for fabrication of free-standing layers of the semi-polar nitride semiconductor film.
  • the free-standing nitride film was obtained by chemical etching of the silicon oxide layer below the graphene layer by using HF/buffered HF etchants. This separated the nitride layer on the graphene from the substrate and releases the nitride layer as a free standing membrane, which was then transferred to other materials, such as glass or flexible plastic substrates.
  • the group III nitride semiconducting material manufactured by the method of the present invention can thus be used advantageously as substrates for a range of optoelectronic device applications such as LEDs, lasers, transistors and the like.
  • a device preferably an optoelectronic device was fabricated comprising Group Ill-nitride semiconducting material comprising of graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on said nitride nucleation /buffer layer with or without a suitable substrate.
  • Group Ill-nitride semiconducting material comprising of graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on said nitride nucleation /buffer layer with or without a suitable substrate.
  • Group Ill-nitride semiconducting material comprising of graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on said nitride nucleation /buffer layer with orientations selected from polar, non-polar and semi-polar comprises one or more layers of dissimilar compositions of the (Al, Ga, In, B) N alloy family selected from the group comprising at least one or more of GaN, AIN, InN, AIGaN, AIInN, InGaN or AIGaInN. :GaN, AIN, InN alloys.
  • the present invention provides for planar free standing layers/ membrane of said Group Ill-nitride semiconducting material scalable to large area and advantageously transferable to a wide variety of substrates selected from glass or flexible plastic substrates thereby favouring fabrication of various optoelectronic devices including LEDs, lasers, transistors, wherein said graphene based group Ill-nitride semiconducting film involves semi-polar orientation selected from (10-11), (11-22), (10- 13) as a single phase material.

Abstract

Group III-nitride semiconducting materials comprising a graphene based layer having thereon at least one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and at least one group III-nitride semiconducting film selected from alloy family of (Al,Ga,In,B) N on said nitride nucleation/buffer layer, in orientations selected from polar, non-polar and semi-polar with or without a suitable underlying substrate, and planar free-standing said Group III-nitride semiconducting material that is advantageously transferable to a wide variety of substrates selected from glass or flexible plastic substrates and adapted for the fabrication of various optoelectronic devices including LEDs, lasers, transistors.

Description

TITLE: GROUP III-NITRIDE SEMICONDUCTING MATERIAL AND A METHOD OF MANUFACTURING THE SAME
FIELD OF INVENTION
The present invention relates to Group Ill-nitride semiconducting materials comprising a graphene based layer having thereon at least one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group III- nitride semiconducting film selected from alloy family of (AI,Ga,In,B) N on said nitride nucleation/buffer layer, in orientations selected from polar, non-polar and semi-polar with or without a suitable underlying substrate. The said Group Ill-nitride semiconducting film in the semiconducting material of the present invention comprises one or more layers of dissimilar compositions of the (Al, Ga, In, B) N alloy family selected from at least one or more of: binary GaN, AIN, InN compound semiconductors; ternary alloys of AIGaN, AIInN, InGaN ; or quaternary alloys of AIGalnN and the like, in said film. The present invention more particularly relates to planar, free-standing said Group Ill-nitride semiconducting material comprising graphene as the selective intermediate layer having deposited thereon at least one Group Ill-nitride semiconducting film in semi-polar orientations such as (10-11), (11-22), (10-13), wherein said graphene as the selective intermediate layer having at least one nitride nucleation/ buffer layer allows the growth of said Group III nitride semiconducting film in said semi-polar orientations. Also the present invention relates to an improved method of manufacturing said planar, group Ill-nitride semiconducting material scalable to large area preferably in semi-polar orientation, and more preferably, also relates to a method of providing free standing layers/ membrane of said group-Ill nitride semiconducting material that is advantageously transferable to a wide variety of substrates selected from glass or flexible plastic substrates and adapted for the fabrication of various optoelectronic devices including LEDs,' lasers, transistors. BACKGROUND ART
Gallium nitride and related ternary and quaternary alloys are well-established as important materials for light emitting diodes and lasers in the UV/visible region. In general, the most stable crystal structure of group III nitrides is the hexagonal wurtzite form. Further, most single crystal thin films of the group III nitrides are grown on the basal plane, i.e. the c-plane or (0001) oriented plane. In this orientation, the alternating layers of Gallium and Nitrogen atoms lead to a spontaneous polarization that induces an internal electric field. In addition, most nitrides are grown on sapphire, in which lattice mismatch results in strain, which further leads to piezoelectric polarization.
Such internal electric fields are often deleterious for optoelectronic devices as they reduce the recombination efficiency of electrons and holes and also make it difficult to push towards the optical emission of lasers and LEDs to longer wavelengths. The problem of polarization is most acute on standard basal plane (0001) of the wurtzite crystal structure. There are other crystal planes perpendicular to the (0001) plane which have equal number of group III and group V atoms, and hence form "non-polar" surfaces. Materials grown on the so-called a-plane [11-20] and m-plane [1-100] directions thus have no net polarization field in the growth direction. Unfortunately, inspite of worldwide efforts on synthesis of non-polar nitrides, there are still difficulties related to obtaining smooth layers as well as there exist problems with indium incorporation in non-polar oriented epilayers.
Furthermore, there exist other planes of wurtzite structure which are at an angle to the basal plane and offer not non-zero, but greatly reduced polarization fields compared to the c-plane. (Such "semi-polar" planes have both two non-zero h, i, or k Miller indices, and a non-zero I Miller index - examples being {11-22}, {10-11}, {10-13} etc.). It is well known from recent experimental studies that these planes are advantageous from the growth standpoint as they offer increased indium incorporation for InGaN quantum wells as well as are smoother and more homogenous layers compared to growth on non- polar orientations. Such semi-polar layers have been used to demonstrate green LEDs and lasers.
Polarization-related issues are a major cause of concern in the performance of these devices, especially in the widely used crystal orientation-the standard basal plane (0001) of the wurtzite crystal structure. Recent experimental evidence suggests that the use of "semi-polar" planes (wurtzite crystal planes such as {11-22}, {10-11}, {10-13} etc.) are advantageous for optoelectronic devices, and such semi-polar layers have been used to demonstrate the best green LEDs and lasers. Unfortunately there is no easy way to grow semi-polar nitride layers on sapphire, even using misoriented substrates.
Till date there is no facile way to produce large area (tens to hundreds of cm2) semi- polar nitride films that would be useful for large-scale industrial applications. Most currently available semi-polar films utilize quasi-bulk semi-polar GaN substrates, which are made by cutting boules of HVPE grown GaN nitrides along semi-polar directions resulting in substrates which are typically only a few mm across and limited by the thickness of the starting HVPE material.
US Patents including US 7,687,293, US 7,575,947, US 7,790,584 and US 7,704,324 disclose methods for growing a semi-polar nitride semiconductor thin film on a substrate, all of which require either a complicated multi-step etch, or re-growth processes, or achieve the semi-polar surface only in certain regions of the wafer, or require miscut /(Disoriented substrates.
Graphene has been a material of contemporary research interest as it can serve as a transparent conducting electrode for use in various optoelectronic devices. However the growth of Ill-Nitride materials such as GaN on graphene has not received much attention possibly due to the chemical inertness of the graphene surface. A recent publication by Chung et al. (Science, 310, 655, 2010) claims that GaN nucleation does not occur on the basal plane of pristine graphene, and some GaN islands grow on roughened graphene surfaces subjected to Oxygen-plasma treatment. They say that even the typical two-temperature growth process using a low-temperature GaN buffer layer does not improve the film properties. Hence they use zinc oxide as an intermediate layer for GaN growth. Thus there is still no clear method for achieving the growth of planar large-area films of Ill-Nitride semiconductors on graphene.
As apparent from the above, there is therefore a longfelt need in the art to overcome the deficiencies of the prior art methods to develop planar group Ill-nitride semiconducting material with semi-polar orientations and a method for growing said material on substrates which would not need any special miscut / misoriented substrates, which method would be scalable, useful for large scale industrial applications and would be industrially facile in not involving a multi-step process such as not requiring plasma processing and re-growth thereafter. Also there is a strong need in the art to explore methodologies that would be advantageous in simultaneously providing for free standing layers/ membrane of said group Ill-nitride semiconducting material transferable to a wide variety of substrates for the purpose of fabrication of wide range of optoelectronic devices.
OBJECTS OF THE INVENTION
It is thus a primary object of the present invention to provide for planar group Ill-nitride semiconducting (Al, Ga, In, B)N material with one or more orientations selected from polar, non-polar and semi-polar, preferably with semi-polar orientations such as (lull), (11-22), (10-13) as a single phase material and a simple yet improved method for manufacturing the same.
It is another object of the present invention to provide for free standing layers/ membrane of said group Ill-nitride semiconducting (Al, Ga, In, B)N material to enable fabrication of wide range of optoelectronic devices including LEDs, lasers, transistors involving said free-standing layers/ membrane and a method to achieve the same involving the steps of lifting off the group Ill-nitride material from the substrate on which it is deposited so as to transfer it to another substrate.
It is another object of the present invention to provide for a method of fabricating said group Ill-nitride semiconducting material under appropriate growth conditions by depositing a selective intermediate layer on a substrate prior to the growth of the nitride semiconducting layer to enable growth of said material in said semipolar orientations.
It is yet another object of the invention to provide a method of growing planar, group Ill-nitride semiconducting (AI,In,Ga,B)N material that would be easily scalable to large area and useful for large scale industrial applications.
It is yet another object of the present invention to provide for a method of manufacturing nitride semiconducting (AI,In,Ga,B)N material that would not require specially miscut/ mis-oriented substrates.
SUMMARY OF THE INVENTION
Thus according to the basic aspect of the present invention there is provided a Group III- nitride semiconducting material comprising of graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on said nitride nucleation /buffer layer. It is by way of the present invention that it has been possible to provide at least one nitride nucleation/buffer layer adapted for conformal coverage of entire graphene based layer and thereon providing for atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on sajd nitride nucleation /buffer layer, that enabled the provision of the much desired single phase semiconducting material and preferably even in semi-polar orientations. The single phase semiconducting material of the present invention which involves a graphene based layer is also advantageous in that the same is easily scalable to large area and also advantageously transferable to a wide variety of substrates selected from glass or flexible plastic substrates adapted as free standing layers/ membrane of said Group Ill-nitride semiconducting material favouring fabrication of various optoelectronic devices.
According to another preferred aspect of the present invention there is provided said Group Ill-nitride semiconducting material wherein said group Ill-nitride semiconducting films of (Al, Ga, In, B) N comprise at least one or more layers of dissimilar compositions within the alloy family of (AI,Ga,In,B)N.
According to yet another preferred aspect of the present invention there is provided said Group Ill-nitride semiconducting material wherein graphene based group Ill-nitride semiconducting film is planar with one or more orientations selected from polar, non- polar and semi-polar and selected from the group comprising of GaN, AIN, InN, AIGaN, AIInN, InGaN and AIGalnN.
According to another preferred aspect of the present invention there is provided said Group Ill-nitride semiconducting material wherein said graphene based group Ill-nitride semiconducting films comprise one or more layers of dissimilar compositions of the (Al, Ga, In, B) N alloy family selected from at least one or more of: GaN, AIN, InN alloys; ternary alloys of AIGaN, AIInN, InGaN; or quaternary alloys of AIGalnN and the like, in said film. According to another aspect of the present invention there is provided Group Ill-nitride semiconducting material wherein said graphene based group Ill-nitride semiconducting films comprise free standing graphene based films with one or more orientations selected from polar, non-polar and semi-polar preferably with semi-polar orientations selected from (10-11), (11-22), (10-13) as a single phase material.
According to another preferred aspect of the present invention there is provided said Group Ill-nitride semiconducting material wherein said graphene based group Ill-nitride semiconducting free standing films shaped and configured for variety of applications.
Said graphene based group Ill-nitride semiconducting films are provided on suitable substrates include rigid substrates preferably including glass or transparent conducting oxide (TCO) coated glass, and/or flexible substrates preferably including plastics or metal foils.
More preferably, said Group Ill-nitride semiconducting material wherein said nitride nucleation/buffer layer adapted for conformal coverage of entire graphene surface comprise is an alloy selected from combinations of alloy family (Al, In, Ga)N preferably AIN.
According to another aspect of the present invention there is provided said Group III- nitride semiconducting material comprising said graphene based group Ill-nitride semiconducting films on suitable substrates including sapphire, patterned sapphire, silicon, silicon oxide /dioxide coated silicon, silicon nitride coated silicon, silicon carbide and glass. According to another aspect of the present invention there is provided said graphene based group Ill-nitride semiconducting films adapted as free standing films on releasable sacrificial substrate layers including silicon oxide/dioxide, silicon nitride, spin-on-glass, polyimides. According to another aspect of the present invention there is provided said graphene Group Ill-nitride semiconducting films scalable to a large area from 10s to about 100s of cm2 adapted for various optoelectronic devices.
According to another aspect of the present invention there is provided a Group Ill-nitride semiconducting material comprising of graphene based layer having thereon at least one AIN nucleation /buffer layer having conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (Al, Ga, In, B)N on said nitride nucleation /buffer layer with semi-polar orientations selected from (10-11), (11-22), (10-13).
According to another aspect of the present invention there is provided a method of manufacture of Group Ill-nitride semiconducting material comprising a) providing a graphene based layer on a substrate;
b) providing said nitride nucleation /buffer layer having conformai coverage on entire graphene based layer; and
c) providing thereon said nucleation /buffer layer, atieast one group Ill-nitride semiconducting film selected from alloy family of (Al, Ga, In, B)IM to obtain therefrom graphene based group III nitride semiconducting films of desired thickness.
According to another preferred aspect of the present invention there is provided a method of manufacture of Group Ill-nitride semiconducting material comprising a) providing a graphene based layer on a substrate;
b) providing said AIN nucleation /buffer layer having conformai coverage on entire graphene based layer; and
c) providing thereon said AIN nucleation /buffer layer having conformai coverage, atieast one group Ill-nitride semiconducting film selected from alloy family of (Al, Ga, In, B)N to obtain therefrom graphene based group III nitride semiconducting films of desired thickness.
The single phase semiconducting material of the present invention could avoid the limitations of achieving graphene based semiconducting materials with planar large area films by the above control of process parameters whereby even in the absence of specially miscut or mis-oriented sapphire or spinel substrates allows attainment of said Group Ill-nitride semiconducting material as a single phase material of high material quality with preferred semi-polar orientations that is advantageously both scalable to large area and also transferable to a wide variety of substrates adapted as free standing layers/ membrane of planar large-area films of said Group Ill-nitride semiconductors.
Preferably, said nitride nucleation /buffer layer is grown on said graphene layer such as to achieve said conformai coverage on entire graphene based layer followed by growing thereon said nitride nucleation /buffer layer the said nitride semiconducting film involving a semiconductor deposition system and following one or more of techniques selected from metal organic chemical vapor deposition ( OCVD), metal organic vapour phase epitaxy ( OVPE), solid or gas source molecular beam epitaxy (MBE), and hydride vapor phase epitaxy (HVPE). More preferably, said nitride semiconducting film is grown in one or more orientations selected from polar, non-polar and semi-polar. According to another aspect of the present invention said step (b) of providing a nucieation /buffer layer having conformal coverage on entire graphene based layer comprises the steps of
(i) surface conditioning of the graphene based layer on the substrate followed by thermal cleaning in the temperature range of 900°C to 1100°C for 3 to 10 min. followed by cooling;
(ii) growing stagewise said nitride nucieation /buffer layer involving required metalorganic and hydride precursors for nucieation of desired thickness under required system pressure and temperature.
According to another preferred aspect of the present invention said step of providing AIN as nucieation /buffer layer comprises growing said nucieation /buffer layer involving precursors for nucieation involving low pressure in the range of 20 to 100 Torr following stepwise growth preferably involving either (A) two stage growth comprising (i) following a first stage growth for thickness in the range of 10 to 20 nm at temperature in the range of 700 to 800°C followed by (ii) second stage growth for thickness in the range of 25 to 40 nm at temperature in the range of 1000 to 1100 °C or (B) three stage growth (i) following a first stage growth for thickness in the range of 10 to 20 nm at temperature in the range of 600 to 700 °C (ii) second stage growth for thickness in the range of 10 to 20 nm at temperature in the range of 800 to 950 °C and (Mi) third stage growth for thickness in the range of 20 to 30 nm at temperature in the range of 1000 to 1100 °C .
According to another aspect of the present invention said step (c) of providing thereon said nitride nucieation /buffer layer, the group III nitride semiconducting film comprises the steps of providing required metalorganic and hydride precursors in the pressure ranging from 20 to 760 Torr, temperature ranging from 530 to 1100 °C, depending on the particular Ill-Nitride film deposited. According to another preferred aspect of the present invention there is provided said method for providing preferred semipolar orientation (10-11) of Group Ill-nitride semiconducting material the said atleast one nitride nucieation /buffer layer is grown in said semipolar orientation (10-11) involving precursors for nucieation and growth in the preferred temperature range of 600 to 1100 °C and pressure in the range of 20 to lOOTorr and with selective V/III ratio in the range of 3500 to 10000. According to yet another aspect of the present invention wherein for providing a preferred semipolar orientation (10-11) of Group Ill-nitride semiconducting material, said AIN as nucleation /buffer layer is grown in said semipolar orientation (10-11) involving precursors for nucleation and growth involving trimethylaluminium, ammonia and hydrogen carrier gas in the preferred temperature range of 600 to 1100 °C preferably about 1000 °C and pressure in the range of 20 to 100 Torr, preferably 50 Torr and with selective V/III ratio in the range of 2500 to 10000 preferably above 3500.
According to yet another preferred aspect of the present invention wherein for providing preferred semipolar orientation (10-11) of GaN semiconducting film provided thereon said nitride nucleation /buffer layer comprises growing the GaN film involving trimethylgallium, ammonia and hydrogen carrier gas, at 50 to 200 Torr preferably 50 Torr reactor pressure at temperature 1000 to 1100°C preferably of 1040°C to thereby obtain semi-polar oriented said GaN group III nitride semiconducting film as a single phase material.
According to another preferred aspect of the present invention for providing preferred semipolar orientation (10-11) of Group Ill-nitride semiconducting material wherein providing thereon said AIN nitride nucleation /buffer layer, preferably AIGaN as the group III nitride semiconducting film comprises growing said Group Ill-nitride film involving selective precursor involving trimethylgallium, trimethylaluminium and ammonia and hydrogen carrier gas, at 50 to 100 Torr preferably 50 Torr reactor pressure at temperature 1000 to 1100°C preferably of 1040°C to thereby obtain semi-polar oriented said group III nitride semiconducting film comprising AIGaN semi-polar (10-11) layer adapted as a single phase material.
According to another preferred aspect of the present invention for providing preferred semipolar orientation (10-11) of Group Ill-nitride semiconducting material wherein providing thereon said AIN nitride nucleation /buffer layer, InN or InGaN or as the group III nitride semiconducting film comprises growing the Group Ill-nitride film involving selective precursor involving trimethylindium, trimethylgallium, and ammonia and nitrogen carrier gas, at 200 to 500 Torr reactor pressure at temperature 530 to 800°C to thereby obtain semi-polar oriented said group III nitride semiconducting film comprising InN semi-polar (10-11) layer or InGaN semi-polar (10-11) layer adapted as a single phase material.
According to yet another preferred aspect of the method of the present invention said substrate is selected from a group comprising of Sapphire, patterned Sapphire, Silicon, Silicon Oxide/Dioxide coated Silicon, Silicon Nitride coated Silicon, Silicon Carbide and Glass also comprising releasable sacrificial substrate layers including silicon oxide/dioxide, silicon nitride, spin-on-glass, polyimides.
Preferably, said substrate is surface conditioned prior to deposition of said nitride semiconducting film by exposure to oxygen plasma after which thermal cleaning of the substrate is preferably achieved by heating under hydrogen flow just prior to growth in the semiconductor deposition system.
According to another aspect of the present invention there is provided a method comprising obtaining free standing graphene based group III nitride semiconducting films comprising
a) providing a graphene based layer on a sacrificial substrate;
b) providing said nitride nucleation /buffer layer having conformal coverage on entire graphene based layer;
c) providing thereon said nucleation /buffer layer having conformal coverage, atleast one group Ill-nitride semiconducting film selected from alloy family of (Al, Ga, In, B)N to obtain therefrom graphene based group III nitride semiconducting films of desired thickness; and d) removing the sacrificial layer to thereby obtain free standing Group Ill-nitride semiconducting material.
According to another aspect of the present invention there is provided a method comprising obtaining free standing graphene based group III nitride semiconducting films wherein said sacrificial substrate is selected from silicon oxide/ dioxide, silicon nitride, spin-on-glass, polyimides which is removed preferably by chemical etching of the said sacrificial layer, e.g. the silicon dioxide layer below said graphene layer is etched using HF/buffered HF. According to another aspect of the present invention there is provided an optoelectronic device comprising Group Ill-nitride semiconducting material comprising of graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on said nitride nucleation /buffer layer with or without a suitable substrate.
According to yet another aspect of the present invention there is provided a semiconducting material adapted for facilitating epitaxial growth of semiconducting films as epilayer thereon comprising of graphene based layer and atleast one nitride nucleation /buffer layer comprising an alloy selected from combinations of alloy family (Al, In, Ga)N having conformal coverage of entire graphene surface with or without a suitable substrate.
The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying figures & tables and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein. BRIEF DESCRIPTION OF FIGURES
Fig. 1: depicts scanning electron microscope image showing conformal coverage of entire surface with AIN buffer layer on graphene;
Fig. 2 (a): scanning electron microscope image showing conformal coverage of entire surface with GaN deposited on top of AIN nucleation and buffer layer on Graphene; 2(b) depicts scanning electron microscope image showing the absence of conformal growth of GaN on the entire surface due to its deposition directly on Graphene;
Fig. 3: depicts X-ray diffraction (XRD) profiles of the ω-2θ scan for on-axis reflections for AIN layers grown on graphene at (a) different substrate temperatures and (b) different V/III ratios;
Fig. 4: depicts X-ray diffraction (XRD) profiles of the ω-2θ scan for on-axis reflections showing AIN buffer layer and GaN semi-polar layer (10-11) grown on graphene;
Fig. 5: depicts room temperature photoluminescence emission spectra from the semi- polar (10-11) oriented GaN and AIGaN layers showing high material quality;
Fig. 6: depicts X-ray diffraction (XRD) profiles of the ω-2θ scan for on-axis reflections showing patterns of GaN on AIN on graphene grown under different conditions showing mixed phases at low temperature; Fig. 7: depicts X-ray diffraction (XRD) profiles of the ω-2θ scan for on-axis reflections of AIGaN alloy samples of varying aluminium content
Fig. 8(a) depicts a process of lift off of free standing GaN layer, after etching the underlying silicon dioxide layer in buffered HF (Fig.8 b), the nitride layer floats up on to the surface (Fig. 8 c), Fig. 8 (d) depicts free-standing GaN layer transferred to a glass slide, and Fig. 8 (e) is a x-ray diffraction pattern of the free-standing GaN showing a semi-polar orientation (10-11). Fig 8 (f) shows room temperature photoluminescence from the free-standing GaN layer, pointing to the high material quality.
DETAILED DESCRIPTION OF THE INVENTION
As discussed hereinbefore, the present invention provides for Group Ill-nitride semiconducting material comprising graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and at least one group Ill-nitride semiconducting film selected from alloy family of (Al, Ga, In, B)N on said nitride nucleation /buffer layer, in orientations selected from polar, non-polar and semi-polar with or without a suitable substrate. The said Group Ill- nitride semiconducting film of the semiconducting material of the present invention comprises one or more layers of dissimilar compositions of the (Al, Ga, In, B) N alloy family selected from at least one or more of: GaN, AIN, InN alloys; ternary alloys of AIGaN, AIInN, InGaN; or quaternary alloys of AIGalnN and the like.
More particularly, the present invention provides for planar free standing semiconducting material scalable to large area and advantageously transferable to a wide variety of substrates selected from glass or flexible plastic substrates thereby favouring fabrication of various optoelectronic devices including LEDs, lasers, transistors wherein said III- nitride semiconducting film preferably involves semi-polar orientation such as (10-11), (11-22), (10-13).
In an embodiment, the present invention relates to a method of growing planar group Ill-nitride semiconducting film (AI,Ga,In,B)N on a substrate comprising steps of:
a) deposition of graphene layer on the substrate; and
b) deposition of a conformal nitride semiconducting film on the graphene layer adapted for facilitating epitaxial growth of semiconducting films as epilayer thereon.
The nitride semiconducting film grown by the present method can be deposited more of orientations selected from polar, non-polar and semi-polar orientations. By appropriate choice of growth conditions semi-polar orientations such as (10-11), (11- 22), (10-13) etc. can be obtained. In another embodiment, the planar group III nitride semiconducting film that is grown may contain one or more layers of dissimilar compositions of the (AI,Ga,In,B)N alloy family. For example, films which can be grown by the present method can be one or more of GaN, AIN, InN; ternary alloys like AIGaN, AIInN, InGaN; or quaternary alloys like AIGalnN and the like.
In an embodiment, the planar group III nitride semiconducting film can be grown using one or more techniques selected from metal organic chemical vapor deposition (MOCVD), metalorganic vapour phase epitaxy (MOVPE), solid and gas source molecular beam epitaxy (MBE), or hydride vapor phase epitaxy (HVPE).
In an embodiment of the present invention, the group Ill-nitride semiconducting film is grown in a semi-polar orientation which is selected from (10-11), (10-13) and (11-22).
In an embodiment, semi-polar group Ill-nitride semiconducting film can be grown on substrates such as Silicon, Sapphire, Silicon Carbide, or Silicon-dioxide/Silicon-nitride coated Silicon substrates using a graphene interlayer. The present method does not require specially miscut or mis-oriented sapphire or spinel substrates.
Large area graphene layers used in the present invention can be synthesized using standard Chemical Vapor Deposition (CVD) techniques as disclosed in the literature, for example, through deposition by cracking of methane at high temperature on copper (or nickel) foils, followed by etching and lift-off. (See, for example, Mark Borysiak, "Graphene Synthesis by CVD on Copper Substrates, The 2009 NNIN REU Research Accomplishments, p. 71 to 74 and Matthew O'Brien et al, "CVD Synthesis and Characterization of Graphene Thin Films", Army Research Laboratory, 2010, p. 1 to 15, http: //www.arl.army.mil/arlreports/2010/ARL-TR-5047.pdf. and for synthesis on nickel, see for example, K-S. Kim, et al, Nature 457, 706-710 (2009).
The invention and its advantages are explained hereunder in greater detail in relation to the following non-limiting exemplary illustrations: Example I
In accordance with an aspect of the present invention, surface conditioning of the graphene layer prior to deposition of nitride layer was done by exposure to oxygen plasma.
Thereafter, the wafer was loaded into an MOVPE reactor and heated under hydrogen flow and thermally cleaned, typically at 1040°C for 5 min before cooling down for deposition of the nucleation or buffer layer.
Example-II
Under this example the manufacture of Gr. Ill nitride-semiconducting film involving the graphene based layer following direct deposition of GaN on graphene and with deposition of GaN after conformal coverage of the graphene with nucleation/buffer layer was studied.
As a preferred embodiment, the nitride nucleation or buffer layer used was AIN, which was grown conformally as detailed below on the graphene layer (Fig. 1), hence permitting the growth of smooth layers of GaN on top of it (Fig 2a), whereas direct deposition of GaN on the graphene layer (at 1040 °C 50 Torr) results in isolated island growth (Fig. 2b).
The process for generating the conformal coverage of the nucleation layer on the graphene followed was as hereunder:
An aluminium nitride nucleation or buffer layer was deposited on the graphene layer under appropriate reactor pressure and temperature. In one embodiment, the AIN nucleation layer was grown at a low reactor pressure, for example, 50 Torr, and either as a two step growth - for example, low temperature nucleation step of 15 nm at 600°C, followed by a high temperature grown layer 35 nm at 1040°C, or as a 3-step growth with a low temperature nucleation step of 15 nm at 600°C, followed by 15 nm growth at 900°C, and a high temperature grown buffer layer 35 nm at 1040°C.
The reactor temperature was further ramped to an appropriate temperature for growth of desired group Ill-nitride semiconducting epilayer. The reactor temperature, ranged from 1040°C for GaN to 530°C for InN. Example III Under this example, in accordance with the present invention, the desired group III- nitride semiconducting epilayer was grown on top of an AIN buffer layer by admitting the appropriate metalorganic and hydride precursors at a specific pressure, temperature, V/III ratio, and growth rate to favour a preferential surface orientation of the epilayer. It was noted that typically high temperature and low pressure conditions favored the growth of semi-polar oriented layers while low temperature and high pressure conditions lead to mixed phases with polar and semi-polar oriented domains.
Example IV Under this example, AIN layers were grown using trimethylaluminium and ammonia and hydrogen carrier gas, at growth temperatures ranging from 800°C to 1100°C and V/III ratios from 500 to 5000. Fig. 3 (a) shows the X-ray diffraction (XRD) of the ω-2θ scan for on-axis reflections for a series of AIN layers grown at different growth temperatures in the range 900 to 1040°C keeping other parameters fixed. From the accompanying figure it can been seen at lower temperatures mixed phases are obtained, as the temperature increases the intensity of the (0002) peak drops, and reached a minimum at an optimum temperature of 1000°C. Fig. 3(b) shows a series of AIN layers growth at different V/III ratios from 500 to 4500 keeping other parameters fixed. From the figure it can be seen that for growth at low V/III ratio other parasitic phases such as the (0002), (10-12) and (11-20) are seen. These phases reduce on increasing the V/III ratio, and almost single phase (10-11) semipolar AIN is obtained at V/III ratios above 3500.
Example V
In accordance with a preferred aspect of the invention, under this example, GaN and AIGaN layers, were grown using trimethylgallium, trimethylaluminium and ammonia and hydrogen carrier gas, growth at 1040°C and 50 Torr reactor pressure leading to layers with a preferential (10-11) orientation (Fig. 4) Fig. 4 shows the X-ray diffraction (XRD) profile of the ω-2θ scan for on-axis reflections showing AIN buffer layer, GaN semi-polar (10-11) layer and AIGaN semi-polar (lO-l l)layer grown on graphene. A single phase material was thus obtained. Fig. 5 shows the room temperature photoluminescence from these GaN and AIGaN layers pointing to the high quality of the material. Growth at 900°C and 200 Torr reactor pressure lead to layers with mixed (10-11) and (0002) orientation (Fig. 6). Fig. 6 shows the X-ray diffraction (XRD) profile of the ω-2θ scan for on-axis reflections showing patterns of GaN on AIN on graphene grown under different conditions showing mixed phases at low temperature.
By varying the relative amounts of trimethylaluminium and trimethylgalliunn supplied during growth it was possible to adjust the composition of the AIGaN alloy layer to any desired aluminium mole fraction, as shown in Fig. 7 by the typical X-ray diffraction (XRD) profiles of the ω-2θ scan for on-axis reflections for 4 samples covering the range of Al content from 0 to 100%.
InN and In-containing alloys were grown in a similar manner as described herein, but by using nitrogen carrier gas instead of hydrogen. After a group III nitride semiconducting layer of a desired thickness was grown, the supply of reagents was switched off and the reactor cooled to room temperature and the sample removed.
The planar group III nitride films obtained by the present method are found to be advantageously of a large area, limited only by the size of the graphene layer transferred onto the substrate. Since CVD graphene can be grown over large areas (10s to 100s of cm2), semi-polar nitride films of large area can thus be obtained by the method of the present invention. Example VI
In accordance with yet another aspect of the invention, under this example, the graphene layer was transferred to a silicon dioxide or silicon nitride coated substrate (wafer). The silicon dioxide/nitride served as a sacrificial layer in a process for the fabrication of free standing semiconductor layers.
In a further embodiment, the method of the present invention provides for fabrication of free-standing layers of the semi-polar nitride semiconductor film. In another preferred embodiment of the present invention, the free-standing nitride film was obtained by chemical etching of the silicon oxide layer below the graphene layer by using HF/buffered HF etchants. This separated the nitride layer on the graphene from the substrate and releases the nitride layer as a free standing membrane, which was then transferred to other materials, such as glass or flexible plastic substrates. (Fig. 8) The group III nitride semiconducting material manufactured by the method of the present invention can thus be used advantageously as substrates for a range of optoelectronic device applications such as LEDs, lasers, transistors and the like.
Example VII
A device preferably an optoelectronic device was fabricated comprising Group Ill-nitride semiconducting material comprising of graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on said nitride nucleation /buffer layer with or without a suitable substrate.
It is thus possible by way of the present invention to provide for Group Ill-nitride semiconducting material comprising of graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on said nitride nucleation /buffer layer with orientations selected from polar, non-polar and semi-polar comprises one or more layers of dissimilar compositions of the (Al, Ga, In, B) N alloy family selected from the group comprising at least one or more of GaN, AIN, InN, AIGaN, AIInN, InGaN or AIGaInN. :GaN, AIN, InN alloys.
Importantly, the present invention provides for planar free standing layers/ membrane of said Group Ill-nitride semiconducting material scalable to large area and advantageously transferable to a wide variety of substrates selected from glass or flexible plastic substrates thereby favouring fabrication of various optoelectronic devices including LEDs, lasers, transistors, wherein said graphene based group Ill-nitride semiconducting film involves semi-polar orientation selected from (10-11), (11-22), (10- 13) as a single phase material.

Claims

We Claim:
1. Group Ill-nitride semiconducting material comprising of graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on said nitride nucleation /buffer layer.
2. Group Ill-nitride semiconducting material as claimed in claim 1 wherein said group Ill-nitride semiconducting films of (Al, Ga, In, B) N comprise at least one or more layers of dissimilar compositions within the alloy family of (AI,Ga,In,B)N.
3. Group Ill-nitride semiconducting material as claimed in anyone of claims 1 or 2 wherein graphene based group Ill-nitride semiconducting film is planar with one or more orientations selected from polar, non-polar and semi-polar and selected from the group comprising of GaN, AIN, InN, AIGaN, AIInN, InGaN and AIGalnN.
4. Group Ill-nitride semiconducting material as claimed in anyone of the preceding claims wherein said graphene based group Ill-nitride semiconducting films comprise one or more layers of dissimilar compositions of the (Al, Ga, In, B) N alloy family selected from at least one or more of: GaN, AIN, InN alloys; ternary alloys of AIGaN, AIInN,. InGaN; or quaternary alloys of AIGalnN and the like, in said film.
5. Group Ill-nitride semiconducting material as claimed in anyone of the preceding claims wherein said graphene based group Ill-nitride semiconducting films comprise free standing graphene based films with one or more orientations selected from polar, non- polar and semi-polar preferably with semi-polar orientations selected from (10-11), (11- 22), (10-13) as a single phase material.
6. Group Ill-nitride semiconducting material as claimed in anyone of the preceding claims comprising said graphene based group Ill-nitride semiconducting free standing films shaped and configured for variety of applications.
7. Group Ill-nitride semiconducting material as claimed in anyone of the preceding claims comprising said graphene based group Ill-nitride semiconducting films on suitable substrates including rigid substrates preferably including glass, transparent conducting oxide (TCO) coated glass and/or flexible substrates preferably including plastics, metal foils.
8. Group Ill-nitride semiconducting material as claimed in any of the preceding claims wherein said nitride nudeation /buffer layer adapted for conformal coverage of entire graphene surface comprise an alloy selected from combinations of alloy family (Al, In, Ga)N preferably AIN.
9. Group Ill-nitride semiconducting material as claimed in any of the preceding claims comprising said graphene based group Ill-nitride semiconducting films on suitable substrates including sapphire, patterned sapphire, silicon, silicon oxide /dioxide coated silicon, silicon nitride coated silicon, silicon carbide and glass.
10. Group Ill-nitride semiconducting material as claimed in any of the preceding claims comprising graphene based group Ill-nitride semiconducting films adapted as free standing films on releasable sacrificial substrate layers including silicon oxide/dioxide, silicon nitride, spin-on-glass, polyimides.
11. Group Ill-nitride semiconducting material as claimed in any of the preceding claims comprising graphene based group Ill-nitride semiconducting films scalable to a large area including from 10s to about 100s of cm2 adapted for various optoelectronic devices.
12. Group Ill-nitride semiconducting material comprising of graphene based layer having thereon atleast one AIN nudeation /buffer layer having conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (Al, Ga, In, B)N on said nitride nudeation /buffer layer with semi-polar orientations selected from (10-11), (11-22), (10-13).
13. A method of manufacture of Group Ill-nitride semiconducting material as claimed in anyone of claims 1 to 12 comprising
a) providing a graphene based layer on a substrate;
b) providing said nitride nudeation /buffer layer having conformal coverage on entire graphene based layer; and
c) providing thereon said nucleation/buffer layer, atleast one group Ill-nitride semiconducting film selected from alloy family of (Al, Ga, In, B)N to obtain therefrom graphene based group III nitride semiconducting films of desired thickness.
14. A method of manufacture of Group Ill-nitride semiconducting material as claimed in claim 13 comprising a) providing a graphene based layer on a substrate;
b) providing said AIN nucleation /buffer layer having conformal coverage on entire graphene based layer; and
c) providing thereon said AIN nucleation /buffer layer having conformal coverage, atleast one group Ill-nitride semiconducting film selected from alloy family of (Al, Ga, In, B)N to obtain therefrom graphene based group III nitride semiconducting films of desired thickness.
15. A method as claimed in anyone of claims 13 or 14 wherein said nitride nucleation /buffer layer is grown on said graphene layer such as to achieve said conformal coverage on entire graphene based layer followed by growing thereon said nitride nucleation
*
/buffer layer the said nitride semiconducting film involving a semiconductor deposition system and following one or more of techniques selected from metal organic chemical vapor deposition (MOCVD), metal organic vapour phase epitaxy (MOVPE), solid or gas source molecular beam epitaxy (MBE), and hydride vapor phase epitaxy (HVPE).
16. A method as claimed in claim 13 wherein said nitride semiconducting film is grown in one or more orientations selected from polar, non-polar and semi-polar.
17. A method as claimed in claim 13 wherein said step (b) of providing a nucleation /buffer layer having conformal coverage on entire graphene based layer comprises the steps of
(i) surface conditioning of the graphene based layer on the substrate followed by thermal cleaning in the temperature range of 900°C to 1100°C for 3 to lOmin followed by cooling;
(ii) growing stagewise said nitride nucleation /buffer layer involving required metalorganic and hydride precursors for nucleation of desired thickness under required system pressure and temperature.
18. A method as claimed in anyone of claims 14 to 17 wherein said step of providing AIN as nucleation /buffer layer comprises growing said nucleation /buffer layer involving precursors for nucleation involving low pressure in the range of 20 to 100 Torr following stepwise growth preferably involving either (A) two stage growth comprising (i) following a first stage growth for thickness in the range of 10 to 20 nm at temperature in the range of 700 to 800 °C followed by (ii) second stage growth for thickness in the range of 25 to 40nm at temperature in the range of 1000 to 1100 °C or (B) three stage growth (i) following a first stage growth for thickness in the range of 10 to 20 nm at temperature in the range of 600 to 700 °C (ii) second stage growth for thickness in the range of 10 to 20 nm at temperature in the range of 850 to 950 °C and (iii) third stage growth for thickness in the range of 20 to 30 nm at temperature in the range of 1000 to 1100 °C .
19. A method as claimed in anyone of claims 13 to 18 wherein said step (c) of providing thereon said nitride nucleation /buffer layer, the group III nitride semiconducting film comprises the steps of providing required metalorganic and hydride precursors in the pressure ranging from 20 to 760 Torr, temperature ranging from 530 to 1100 °C, depending on the particular Ill-Nitride film deposited.
20. A method as claimed in anyone of claims 13 to 19 for providing preferred semipolar orientation (10-11) of Group Ill-nitride semiconducting material the said atleast one nucleation /buffer layer is grown in said semipolar orientation (10-11) involving precursors for nucleation and growth in the preferred temperature range of 600 to 1100 °C and pressure in the range of 20 to 100 Torr and with selective V/III ratio in the range of 3500 to 10000.
21. A method as claimed in claim 20 wherein for providing a preferred semipolar orientation (10-11) of Group Ill-nitride semiconducting material, said AIN as nucleation /buffer layer is grown in said semipolar orientation (10-11) involving precursors for nucleation and growth involving trimethylaluminium, ammonia and hydrogen carrier gas in the preferred temperature range of 600 to 1100°C preferably about 1000 °C and pressure in the range of 20 to 100 Torr, preferably 50 Torr and with selective V/III ratio in the range of 2500 to 10000 preferably above 3500.
22. A method as claimed in anyone of claims 13 to 21 wherein for providing preferred semipolar orientation (10-11) of GaN semiconducting film provided thereon said nitride nucleation /buffer layer comprises growing the GaN film involving trimethylgallium, ammonia and hydrogen carrier gas, at 50 to 200 Torr preferably 50 Torr reactor pressure at temperature 1000 to 1100°C preferably of 1040°C to thereby obtain semi- polar oriented said GaN group III nitride semiconducting film as a single phase material.
23. A method as claimed in anyone of claims 13 to 21 for providing preferred semipolar orientation (10-11) of Group Ill-nitride semiconducting material wherein providing thereon said AIN nitride nucleation /buffer layer, preferably AIGaN as the group III nitride semiconducting film comprises growing said Group Ill-nitride film involving selective precursor involving trimethylgallium, trimethylaluminium and ammonia and hydrogen carrier gas, at 50 to 100 Torr preferably 50 Torr reactor pressure at temperature 1000 to 1100°C preferably of 1040°C to thereby obtain semi-polar oriented said group III nitride semiconducting film comprising AIGaN semi-polar (10-11) layer adapted as a single phase material.
24. A method as claimed in anyone of claims 13 to 21 for providing preferred semipolar orientation (10-11) of Group Ill-nitride semiconducting material wherein providing thereon said AIN nitride nucleation /buffer layer, InN or InGaN or as the group III nitride semiconducting film comprises growing the Group Ill-nitride film involving selective precursor involving trimethylindium, trimethylgallium, and ammonia and nitrogen carrier gas, at 200 to 500 Torr reactor pressure at temperature 530 to 800°C to thereby obtain semi-polar oriented said group III nitride semiconducting film comprising InN semi-polar (10-11) layer or InGaN semi-polar (10-11) layer adapted as a single phase material.
25. A method as claimed in anyone of claims 13 to 24 wherein said substrate is selected from a group comprising of Sapphire, patterned Sapphire, Silicon, Silicon Oxide/Dioxide coated Silicon, Silicon Nitride coated Silicon, Silicon Carbide and Glass also comprising releasable sacrificial substrate layers including silicon oxide/dioxide, silicon nitride, spin- on-glass, polyimides.
26. A method as claimed in claim 17 wherein said substrate is surface conditioned prior to deposition of said nitride semiconducting film preferably by exposure to oxygen plasma after which thermal cleaning of the substrate is preferably achieved by heating under hydrogen flow just prior to growth.
27. A method as claimed in anyone of claims 13 to 26 comprising obtaining free standing graphene based group III nitride semiconducting films comprising
a) providing said graphene based layer on a sacrificial substrate;
b) providing said nitride nucleation /buffer layer having conformal coverage on entire graphene based layer;
c) providing thereon said nucleation /buffer layer having conformal coverage, atleast one group Ill-nitride semiconducting film selected from alloy family of (Al, Ga, In, B)N to obtain therefrom graphene based group III nitride semiconducting films of desired thickness; and
d) removing the sacrificial layer to thereby obtain free standing Group Ill-nitride semiconducting material.
28. A method as claimed in claim 27 wherein said sacrificial substrate is selected from silicon oxide/ dioxide, silicon nitride, spin-on-glass, polyimides which is removed preferably by chemical etching of said sacrificial silicon dioxide layer below said graphene layer using HF/buffered HF.
29. An optoelectronic device comprising Group Ill-nitride semiconducting material comprising of graphene based layer having thereon atleast one nitride nucleation /buffer layer adapted for conformal coverage of entire graphene surface and atleast one group Ill-nitride semiconducting film selected from alloy family of (AI,Ga,In,B)N on said nitride nucleation /buffer layer with or without a suitable substrate.
30. A semiconducting material adapted for facilitating epitaxial growth of semiconducting films as epilayer thereon comprising of graphene based layer and atleast one nitride nucleation /buffer layer comprising an alloy selected from combinations of alloy family (Al, In, Ga)N having conformal coverage of entire graphene surface with or without a suitable substrate.
PCT/IN2012/000287 2012-04-20 2012-04-20 Group iii-nitride semiconducting material and a method of manufacturing the same WO2013157014A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/IN2012/000287 WO2013157014A1 (en) 2012-04-20 2012-04-20 Group iii-nitride semiconducting material and a method of manufacturing the same

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/IN2012/000287 WO2013157014A1 (en) 2012-04-20 2012-04-20 Group iii-nitride semiconducting material and a method of manufacturing the same

Publications (1)

Publication Number Publication Date
WO2013157014A1 true WO2013157014A1 (en) 2013-10-24

Family

ID=46881117

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IN2012/000287 WO2013157014A1 (en) 2012-04-20 2012-04-20 Group iii-nitride semiconducting material and a method of manufacturing the same

Country Status (1)

Country Link
WO (1) WO2013157014A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106783553A (en) * 2017-02-24 2017-05-31 苏州大学 Graphene/dielectric material is the III-nitride micron rod structure and preparation method of compound substrate
CN113206003A (en) * 2021-04-07 2021-08-03 北京大学 Method for growing single crystal gallium nitride film on random self-supporting substrate

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7575947B2 (en) 2005-09-09 2009-08-18 The Regents Of The University Of California Method for enhancing growth of semi-polar (Al,In,Ga,B)N via metalorganic chemical vapor deposition
US7687293B2 (en) 2006-01-20 2010-03-30 The Regents Of The University Of California Method for enhancing growth of semipolar (Al,In,Ga,B)N via metalorganic chemical vapor deposition
US7704324B2 (en) 2005-01-25 2010-04-27 General Electric Company Apparatus for processing materials in supercritical fluids and methods thereof
US7790584B2 (en) 2007-12-14 2010-09-07 Samsung Led Co., Ltd. Method of growing semi-polar nitride single crystal thin film and method of manufacturing nitride semiconductor light emitting diode using the same
US20100320445A1 (en) * 2009-06-23 2010-12-23 Oki Data Corporation Separation method of nitride semiconductor layer, semiconductor device, manufacturing method thereof, semiconductor wafer, and manufacturing method thereof
JP2011009268A (en) * 2009-06-23 2011-01-13 Oki Data Corp Method for peeling nitride semiconductor layer, method for manufacturing semiconductor device, and semiconductor device
US20120056237A1 (en) * 2010-09-03 2012-03-08 Samsung Electronics Co., Ltd. Semiconductor compound structure and method of fabricating the same using graphene or carbon nanotubes, and semiconductor device including the semiconductor compound structure
KR20120029248A (en) * 2010-09-16 2012-03-26 삼성엘이디 주식회사 A method for fabricating gan wafer

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7704324B2 (en) 2005-01-25 2010-04-27 General Electric Company Apparatus for processing materials in supercritical fluids and methods thereof
US7575947B2 (en) 2005-09-09 2009-08-18 The Regents Of The University Of California Method for enhancing growth of semi-polar (Al,In,Ga,B)N via metalorganic chemical vapor deposition
US7687293B2 (en) 2006-01-20 2010-03-30 The Regents Of The University Of California Method for enhancing growth of semipolar (Al,In,Ga,B)N via metalorganic chemical vapor deposition
US7790584B2 (en) 2007-12-14 2010-09-07 Samsung Led Co., Ltd. Method of growing semi-polar nitride single crystal thin film and method of manufacturing nitride semiconductor light emitting diode using the same
US20100320445A1 (en) * 2009-06-23 2010-12-23 Oki Data Corporation Separation method of nitride semiconductor layer, semiconductor device, manufacturing method thereof, semiconductor wafer, and manufacturing method thereof
JP2011009268A (en) * 2009-06-23 2011-01-13 Oki Data Corp Method for peeling nitride semiconductor layer, method for manufacturing semiconductor device, and semiconductor device
US20120056237A1 (en) * 2010-09-03 2012-03-08 Samsung Electronics Co., Ltd. Semiconductor compound structure and method of fabricating the same using graphene or carbon nanotubes, and semiconductor device including the semiconductor compound structure
KR20120029248A (en) * 2010-09-16 2012-03-26 삼성엘이디 주식회사 A method for fabricating gan wafer

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
CHUNG ET AL., SCIENCE, vol. 310, 2010, pages 655
K-S. KIM ET AL., NATURE, vol. 457, 2009, pages 706 - 710
MARK BORYSIAK: "Graphene Synthesis by CVD on Copper Substrates", THE 2009 NNIN REU RESEARCH ACCOMPLISHMENTS, pages 71 - 74
MATTHEW O'BRIEN ET AL.: "CVD Synthesis and Characterization of Graphene Thin Films", 2010, ARMY RESEARCH LABORATORY, pages: 1 - 15
WON IL PARK ET AL: "Inorganic nanostructures grown on graphene layers", NANOSCALE, vol. 3, no. 9, 2011, ROYAL SOCIETY OF CHEMISTRY UK, pages 3522 - 3533, XP002687653, ISSN: 2040-3364 *
YOO H ET AL: "Microstructures of GaN thin films grown on graphene layers", ADVANCED MATERIALS 20120124 WILEY-VCH VERLAG DEU, vol. 24, no. 4, 24 January 2012 (2012-01-24), pages 515 - 518, XP002687655, DOI: 10.1002/ADMA.201103829 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106783553A (en) * 2017-02-24 2017-05-31 苏州大学 Graphene/dielectric material is the III-nitride micron rod structure and preparation method of compound substrate
CN106783553B (en) * 2017-02-24 2023-03-17 苏州大学 III-nitride micro-column structure with graphene/dielectric material as composite substrate and preparation method thereof
CN113206003A (en) * 2021-04-07 2021-08-03 北京大学 Method for growing single crystal gallium nitride film on random self-supporting substrate

Similar Documents

Publication Publication Date Title
KR101038069B1 (en) Method of zinc oxide film grown on the epitaxial lateral overgrowth gallium nitride template
EP2313543B1 (en) Growth of planar and semi-polar {1 1-2 2} gallium nitride with hydride vapor phase epitaxy (hvpe)
JP5451280B2 (en) Wurtzite crystal growth substrate, manufacturing method thereof, and semiconductor device
US7794541B2 (en) Gallium nitride-based material and method of manufacturing the same
US20090001416A1 (en) Growth of indium gallium nitride (InGaN) on porous gallium nitride (GaN) template by metal-organic chemical vapor deposition (MOCVD)
US9142723B2 (en) Semiconductor wafer comprising gallium nitride layer having one or more silicon nitride interlayer therein
CN107534074B (en) Epitaxial hexagonal materials on IBAD textured substrates
US10192737B2 (en) Method for heteroepitaxial growth of III metal-face polarity III-nitrides on substrates with diamond crystal structure and III-nitride semiconductors
US20120199952A1 (en) Method for Growth of Indium-Containing Nitride Films
US20110003420A1 (en) Fabrication method of gallium nitride-based compound semiconductor
Izyumskaya et al. Emergence of high quality sputtered III-nitride semiconductors and devices
KR20080098039A (en) Method for enhancing growth of semipolar (al,in,ga,b)n via metalorganic chemical vapor depositon
JP5105258B2 (en) Gallium nitride-based material and manufacturing method thereof
WO2013157014A1 (en) Group iii-nitride semiconducting material and a method of manufacturing the same
Chen et al. Growth of high-quality near-ultraviolet light-emitting diodes used InGaN/GaN multiple quantum wells
Lee et al. Epitaxial growth of crack-free GaN on patterned Si (111) substrate
Khan et al. Selective-area growth of GaN and AlGaN nanowires on N-polar GaN templates with 4° miscut by plasma-assisted molecular beam epitaxy
Nurfahana et al. Growth and characterization of AlN thin film deposited by sol-gel spin coating techniques
Chen et al. Effect of Growth Temperature on Structural Quality of In-Rich Alloys on Si (111) Substrate by RF-MOMBE
US20240047203A1 (en) Monolithic remote epitaxy of compound semi conductors and 2d materials
US20230039342A1 (en) Heteroepitaxial growth method of compound semiconductor materials on multi-oriented semiconductor substrates and devices
Tahan Aluminium nitride (AlN) as buffer layer for deposition of gallium nitride (GaN) thin films on silicon substrates using magnetron sputtering technique
KR100839224B1 (en) Method for manufacturing thick film of gan
Amano MOCVD of nitrides
RU135186U1 (en) SEMICONDUCTOR LIGHT-RADIATING DEVICE

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12761819

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12761819

Country of ref document: EP

Kind code of ref document: A1