CA2393007C - Micro-led arrays with enhanced light extraction - Google Patents

Micro-led arrays with enhanced light extraction Download PDF

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CA2393007C
CA2393007C CA2393007A CA2393007A CA2393007C CA 2393007 C CA2393007 C CA 2393007C CA 2393007 A CA2393007 A CA 2393007A CA 2393007 A CA2393007 A CA 2393007A CA 2393007 C CA2393007 C CA 2393007C
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layer
micro
led
leds
spreader
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CA2393007A1 (en
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Steven Denbaars
Brian Thibeault
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/02Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
    • H01L33/08Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/36Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the electrodes
    • H01L33/38Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the electrodes with a particular shape
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/02Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
    • H01L33/20Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies with a particular shape, e.g. curved or truncated substrate
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/02Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
    • H01L33/20Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies with a particular shape, e.g. curved or truncated substrate
    • H01L33/22Roughened surfaces, e.g. at the interface between epitaxial layers
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/36Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the electrodes
    • H01L33/40Materials therefor
    • H01L33/42Transparent materials

Abstract

This invention describes new LED structures that provide increased light extraction efficiency. The new LED structures include arrays of electrically interconnected micro-LEDs (12) that have an active layer (14) sandwiched between two oppositely doped layers (16, 18). The micro-LEDs are formed on a first spreader layer (18) with the bottom layer (16) of the micro-LEDs in contact with the first spreader (18). A second spreader layer (24) is formed over the micro-LEDs (12) and in contact with their top layer (16). The first spreader layer (18) is electrically isolated from the second spreader layer (24). Each of the spreader layers (20, 24) has a contact (22, 26) and when a bias is applied across the contacts (22, 26), currents spreads to the micro-LEDs (12) and they emit light. The efficiency of the new LED is increased by the increased emission surface of the micro-LEDs (12). Light from each of the micro-LEDs active layer (14) will reach a surface after travelling only a short distance, reducing total internal reflection of the light. Light extraction elements (LEEs) (82, 84, 86, 88, 90, 92, 94) between the micro-LEDs (12) can be included to further enhance light extraction. The new LEDs are fabricated with standard processing techniques making them highly manufacturable at costs similar to standard LEDs.

Description

MICRO-LED ARRAYS WITH ENHANCED LIGHT EXTRACTION
BACKGROUND OF THE INVENTION
Field of the Invention This invention relates to light emitting diodes and more particularly to new structures for enhancing their light extraction.

Description of the Related Art Light emitting diodes (LEDs) are an important class of solid state devices that convert electric energy to light and commonly comprise an active layer of semiconductor material sandwiched between two oppositely doped layers. When a bias is applied across the doped layers, holes and electrons are injected into the active layer where they recombine to generate light. The light generated by the active region emits in all directions and light escapes the device through all exposed surfaces.
Packaging of the LED is commonly used to direct the escaping light into a desired output emission profile.
As semiconductor materials have improved, the efficiency of semiconductor devices has also improved. New LEDs are being made from materials such as GaN, which provides efficient illumination in the ultra-violet to amber spectrum. Many of the new LEDs are more efficient
2 PCT/US00/32084 at converting electrical energy to light compared to conventional lights and they can be more reliable. As LEDs improve, they are expected to replace conventional lights in many applications such as traffic signals, outaoor and indoor displays, automobile headlights and taillights, conventional indoor lighting, etc.
However, the efficiency of conventional LEDs is limited by their inability to emit all of the light that is generated by their active layer. When an LED is energized, light emitting from its active layer (in all directions) reaches the emitting surfaces at many different angles. Typical semiconductor materials have a high index of refraction (n2.2-3.8) compared to ambient air (n=l.0) or encapsulating epoxy (nzzl.5) . According tc Snell' s law, light traveling from a region having a high index of refraction to a region with a low index of refraction that is within a certain critical angle (relative to the surface normal direction) will cross to the lower index region. Light that reaches the surface beyond the critical angle will not cross but will experience total internal reflection (TIR). In the case of an LED, the TIR light can continue to be reflected within the LED until it is absorbed, or it can escape out surfaces other than the emission surface. Because of this phenomenon, much of the light generated by conventional LEDs does not emit, degrading efficiency.
One method of reducing the percentage of TIR light is to create light scattering centers in the form of random texturing on the surface. [Shnitzer, et al., "300 External Quantum Efficiency From Surface Textured, Thin Film Light Emitting Diodes", Applied Physics Letters 63, Page 2174-2176 (1993)]. The random texturing is
3 PCT/US00/32084 patterned into the surface by using sub micron diameter polystyrene spheres on the LED surface as a mask during reactive ion etching. The textured surface has features on the order of the wavelength of light that refract and reflect light in a manner not predicted by Snell's Law due to random interference effects. This approach has been shown to improve emission efficiency by 9 - 30%.
One disadvantage of surface texturing is that it can prevent effective current spreading in LEDs which have poor electrical conductivity for the textured electrode layer, such as the case of p-type GaN. In smaller devices or devices with good electrical conductivity, current from the p and n-type layer contacts spreads throughout the respective layers. With larger devices or devices made from materials having poor electrical conductivity, the current cannot spread from the contacts throughout the layer. As a result, part of the active layer does not experience the current and will not emit light. To create uniform current injection across the diode area, a spreading layer of conductive material is deposited on its surface. However, this spreading layer often needs to be optically transparent so that light can transmit through the layer. When a random surface structure is introduced on the LED surface, an effectively thin and optically transparent current spreader cannot easily be deposited.
Another method of increasing light extraction from an LED is to include a periodic patterning in the emitting surface or internal interfaces which redirects the light from its internally trapped angle to defined modes determined by the shape and period of the surface.
See U.S. Patent No. 5,779,924 to Krames et at. This technique is a special case of a randomly textured
4 PCT/USOO/32084 surface in which the interference effect is no longer random and the surface couples light into particular modes or directions. One disadvantage of this approach is tnat the structure can be difficult to manufacture because the shape and pattern of the surface must be uniform and very small, on the order of a single wavelength of the LED's light. The pattern can also present difficulties in depositing an optically transparent current spreading layer as described above.
An increase in light extraction has also been realized by shaping the LED's emitting surface into a hemisphere with an emitting layer at the center. While this structure increases the amount of emitted light, it s fabrication is difficult. U.S. Patent No. 3, 954,534 tc is Scifres and Burnham discloses a method of forming an array of LEDs with a respective hemisphere above each of the LEDs. The hemispheres are formed in a substrate and a diode array grown over them. The diode and lens structure is then etched away from the substrate. One disadvantage of this method is that it is limited to formation of the structures at the substrate interface, and the lift off of the structure from the substrate results in increased manufacturing costs. Also, each hemisphere has an emitting layer directly above it, which requires precise manufacturing.
U. S. Patent No. 5,793,062 discloses a structure for enhancing light extraction from an LED by including optically non-absorbing layers to redirect light away from absorbing regions such as contacts and also redirect light toward the LED's surface. One disadvantage of this structure is that the non-absorbing layers require the formation of undercut strait angle layers, which can be difficult to manufacture in many material systems.

Another way to enhance light extraction is to couple photons into surface plasmon modes within a thin fil m metallic layer on the LED's emitting surface, which are emitted back into radiated modes. [Knock et al., Applied Phvsics Letter 57, pg. 2327 2329 (1990) ] (Please provide title of article) . These structures rely on the coupling of photons emitted from the semiconductor into surface plasmons in the metallic layer, which are further coupled into photons that are finally extracted. One disadvantage of this device is that it is difficult to manufacture because the periodic structure is a one-dimensional ruled grating with shallow groove depths (<0. 1 um) . Also, the overall external quantum efficiencies are low (1.4-1.5%), likely due to 15 inefficiencies of photon to surface plasmon and surface plasmon-to-ambient photon conversion mechanisms. This structure also presents the same difficulties with a current spreading layer, as described above.
Light extraction can also be improved by angling the 20 LED chip's side surfaces to create an inverted truncated pyramid. The angled surfaces provide TIR light trapped in the substrate material with an emitting surface within the critical angle [Krames, et. al. Applied Physics Letters 75 (1999)] (Please provide title of article) 25 Using this approach external quantum efficiency has been shown to increase from 35% to 50% for the InGaAl P
material system. This approach works for devices in which a significant amount of light is trapped in the substrate. For the case of GaN on sapphire, much of the 30 light is trapped in the GaN film so that angling the LED
chip's side surfaces will not provide the desired enhancement.
Still another approach for enhancing light extractor: is photon recycling. (Shnitzer, et al.
`Ultrahigh spontaneous emission quantum efficiency, 99.7%
internally and 72% externally, from A1GaAs/GaAs/A1GaAs double heterostructures', Applied Physics Letters 62, Page 131-133 ;1993) j . This method relies on LEDs having a hign efficiency active layer that readily convert s electrons and holes to light and vice versa. TIR light reflects off the LED's surface and strikes the active layer, where the light is converted back to an electron-hole pair. Because of the high efficiency of the active layer, the electron-hole pair almost immediately reconverts to light that is again emitted in random direction. A percentage of this recycled light strikes one of the LEDs emitting surfaces within the critical angle and escapes. Light that is reflected back to the active layer goes through the same process again.
However, this approach can only be used in LEDs made from materials that have extremely low optical loss and cannot be used in LEDs having an absorbing current spreading layer on the surface.

SUMMARY OF THE INVENTION
The present invention provides a class of new LEDs having interconnected arrays of micro-LEDs to provide improved light extraction. Micro-LEDs have a smaller active area, in the range of 1 to 2500 square microns, but the size is not critical to the invention. An array of micro-LEDs is any distribution of electrically interconnected micro-LEDs. The arrays provide a large surface area for light to escape each of the micro-LEDs, thereby increasing the usable light from the LED. The new LED can have many different geometries and because it is formed by standard semiconductor process techniques, it s ;~igr.ly manufacturable.
The new LED includes a conductive first spreade r layer witr micro-LEDs disposed on one of its surfaces Each micro-LED has a p-type layer, an n-type layer and an active layer sandwiched between the p- and n-type layers .
E-,tner the p- or n-type layer is a top layer and the other is the bottom layer. Current applied to the first spreader layer spreads into each micro-LED's bottom layer. A second spreader layer is included over the micro-LEDs and current from said second spreader spread into the top layer. When a bias is applied across the first and second spreader layers the micro-LEDs emit-light.
One embodiment of the second spreader is a 15 conductive interconnected grid-like structure having conductive paths over the micro-LEDs, in contact with the top laver of the micro-LEDs. An insulator layer i s included over the array with the grid on the insulator layer, thereby electrically isolating the first spreader 20 layer from the grid.
Alternatively, flip-chip bonding can be used to interconnect the micro-LEDs. Using this method, a n unconnected micro-LED array is first formed and then bonded to an electrically conductive material to provide 25 the array interconnection. In a third embodiment, the grid passes over the micro-LEDs and the p-type, active, and n-type material is under the conductive paths of the grid between the micro-LEDs to electrically isolate the grid from the first spreader layer. This grid-like 30 structure can be designed so that emitted light interacts with a sidewall after traveling a small distance.
The new LED can have LEEs disposed between the micro-LEDs or formed on the side surfaces of the micro-LEDs, to further enhance light extraction. The LEEs act to redirect or focus light that would otherwise be trapped or absorbed through TIR in a standard LED
structure. Their shapes may be curved (convex or concave) :r oiecewise linear with the shape of the structure affecting the light extraction and final output direction of light. LEEs that are placed between the micro-LEDs interact with light escaping from the sides of the micro-LEDs. This interaction helps prevent the light from reflecting back into the LED to be absorbed, thereby increasing the useful light out of the LED.
These and other further features and advantages o f the invention will be apparent to those skilled in the art from the following detailed description, taken together with the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a the new LED with a micro-LED array having an interconnecting current spreading grid on an electrically insulating laver;
FIG. 2 is a sectional view of the new LED shown in FIG. 1 taken along section lines 2-2;
FIG. 3 is a sectional view of another embodiment of the new LED with its micro-LED array bonded to a submount using flip-chip mounting;
FIG. 4 is a plan view of a third embodiment of the new LED conductive interconnect current spreading grid and semiconductor material below the grid paths;
FIG. 5 is a sectional view of the LED shown in FIG.4, taken along section lines 4-4;
FIG. 6 is a plan view of an alternative interconnecting current spreading grid;
FIG. 7 is a plan view of another alternative of an interconnecting current spreading grid;
FIG. 8 shows sectional views of the basic shapes of LEES r,`iat can be integrated within the micro-LEDs;
FIG. 9 is a sectional view of the new LED with different LEEs formed between the micro-LEDs;
FIG. 10 is a sectional view of the new LED with LEEs in the form of randomly textured surfaces;
FIG. 11 is a sectional view of the micro-LED array in FIG. 10., having a current blocking layer directly underneath the current spreading grid;
FIG. 12 is a sectional view of the new LED with LEEs integrated on the micro-LED side surfaces;
FIG. 13 is a sectional view the new LED with curved surface LEEs integrated on the sides of the micro-LEDs;
FIG. 14 is sectional view of the new LED with curved surface LEEs integrated on the sides of and between the micro-LEDs; and FIG. 15 is a sectional view the new LED of FIG. 4 with curved LEEs.

DETAILED DESCRIPTION OF THE INVENTION
FIGs. 1 and 2 show one embodiment of the new LED 10 constructed in accordance with the present invention. It includes an array of micro-LEDs 12 with each micro-LED 12 being isolated and having its own active layer of semiconductor material 14 sandwiched between two oppositely doped layers 16 and 18. In the preferred micro-LED, the top layer 16 is p-type and the bottom layer 18 is n-type, although opposite doping in the layers 16, 18 will also work.
The new LED also includes a first spreading layer 20 that spreads current from the n-contact pad 22 to each micro-LED's bottom layer 18. The contact pad 22 i s referred to as the n-contact pad because in the preferred em: odiment the bottom layer 18 is n-type. An insulating layer 23 is deposited over the micro-LED array, covering each micro-LED and the surface of the first spreader in the gaps between the micro-LEDs. A second spreading _aver, preferably in the form of an interconnected current spreading grid 24, is deposited on the insulating layer with the grid's conductive paths passing over the micro-LEDs. A p-contact 26 is deposited on the grid 24 and current from the contact spreads through the grid to top laver 16 each micro-LED 12. The contact 26 is referred to as the p-contact because in the preferred embodiment the top layer 16 is p-type.
A hole is formed through the insulating layer on top is of each micro-LED and a micro-LED contact 29 is included in each insulating layer hole to provide contact between the grid 24 and the micro-LED's top layer 16. The micro-LEDs (except for the holes) and the surface of the first spreading layer are electrically isolated from the current spreading grid by the insulating layer 23. The entire structure is formed on a substrate 28 and the micro-LEDs form an array that emits light when a bias is applied across the contacts 22 and 26. In another embodiment, a transparent conductive sheet is used as the second spreader in place of the grid 24.
The new LED 10 has enhanced light emission because of the increased emission surface area provided by the isolated micro-LEDs. Light generated from each micro-LED's active layer interacts with the edge of the micro-LED after only a very short distance. If the light is within the critical angle, it escapes from the micro-LED
and contributes to the LED's light emission. The new LED
is especially useful for LED structures in which a portion of emitted light cannot be transmitted to the substrate due to total internal reflection (TIR) at the current spreader-substrate interface. This is th e situation for GaN-based LEDs on sapphire, A1N, or Mg O
suns Crates .
The new LED 10 is manufactured by first depositing the first spreader layer 20 on the substrate 28. An epitaxially grown LED structure with an n-type, p-type and an active layer, is then formed on the first spreader layer 20. The micro-LEDs are formed from the LED
structure by etching away portions of the structure using semiconductor etching techniques such as wet chemical-etching, RIE, Ion Milling, or any other technique used for removing semiconductor material.
Each remaining micro-LED forms an independent and electrically isolated device having an .active layer surrounded by oppositely doped layers 16 and 18. The shape and position of the micro-LEDs 12 can be varied with the preferred shape of each micro-LED being cylindrical. When viewed from above, each micro-LED
appears circular with a diameter of between 1 and 50 microns. The micro-LEDs are preferably formed in a close packed pattern to maximize the usable micro-LED space.
The separation between adjacent micro-LEDs is preferably in the range of 1 to 50 m, although the separation is not critical to this invention. The insulator layer 23 is deposited over the entire structure by various methods such as evaporation, CVD or sputtering. Openings are then etched in the insulator layer 23 above each micro-LED 12. The micro-LED contacts and the electrically conductive grid are then deposited by standard deposition techniques.
The first spreader layer 20 may be either a conductive layer deposited on the substrate or the substrate itself, if it is conductive. Preferred conductive substrates for GaN-based LEDs include GaN or S11--con Carbide (SiC) . SiC has a much closer crystal lattice match to Group III nitrides such as GaN and results in Group III nitride films of high quality-Silicon carbide also has a very high thermal conductivity so that the total output power of Group III nitride devices on silicon carbide is not limited by the thermal dissipation of the substrate (as is the case with some devices formed on sapphire) . SiC substrates are available from Cree Research, Inc., of Durham, North Carolina and methods for producing them are set forth in the scientific literature as well as in a U.S. Patents, Nos.
Re. 34,861; 4,946,547; and 5,200,022.
If the substrate is the current spreading layer, the bottom contact can be deposited by metalization on any of the substrate's exposed surfaces. The preferred LED has micro-LEDs 12 that are AlGaInN based with a p-type surface as its top layer 16. The substrate is sapphire, the first spreader is n-type AlGaInN (or an alloy thereof), and the contact metalization is Al/Ni/Au, Al/Ti/Au, or Al/Pt/Au. The insulating layer 23 can be made of many materials such as, but not limited to, SiN, SiO2, or A1N.
The grid 24 can be any electrically conductive material including metals, semi-metals, and semiconductors. It can be made of Al, Ag, Al/Au, Ag/Au, Ti/Pt/Au, Al/Ti/Au, Al/Ni/Au, Al/Pt/Au or combinations thereof. Alternatively, the grid can be made of a thin semi-transparent metal such as Pd, Pt, Pd/Au, Pt/Au, Ni/Au, NiO/Au or any alloy thereof. The grid 24 can be deposited on the new LED by many conventional methods *i _r, the preferred methods being evaporation or sputtering. in the preferred embodiment, the paths of the current spreading grid 24 are between 1 and 10 m wide.
~he micro-LED contacts 29 can be made of Pt, Pt/Au, Pd, Pa; Au, Ni/Au, NiO, or NiO/Au. The p-contact 26 can be aeposlted on the interconnected grid 24 in various locations to allow current from the contact to spread throughout the grid.
FIG. 3 shows a second embodiment of the LED 30 constructed in accordance with the present invention, utilizing flip-chip mounting. As above, micro-LEDs 32 are formed in an array by etching away semiconductor material of a full LED structure. Each micro-LED 32 has an active layer surrounded by two oppositely doped layers. The micro-LED arrangement and size is similar to the embodiment described above. However, in this embodiment each of the micro-LEDs has angled side surfaces and their top layer is narrower than its bottom layer. Like above, the micro-LED array is formed on a first spreader layer 34 that is formed on a substrate 36. An insulating layer 38 covers the micro-LEDs and the surface of the first spreader between adjacent micro-LEDS. On each micro-LED
32, a hole is included in the insulating layer for a top contact 40 A second spreader layer 42 coats the entire micro-LED array to interconnect the top contacts 40.
The surface of the second spreader 42 opposite the micro-LEDs is bonded to a reflective metallic layer 48 on a submount 46 by a bonding media. A p-contact 44 is included on the metallic layer 48 and current applied to the second contact spreads throughout the second spreader, to the top contacts 40 and to the top layer of the micro-LEDs 32. There is a break in the metallic layer 48 and the n-contact 50 is formed on the portion of the metallic layer 48 that is electrically isolated from the portion havina the p-contact. The finger 49 is bonded between the submount and the first spreader and conduct --s current from the contact 50 through the metallic laye r 45, tr.rougr the finger and to the first spreader 34. The current then spreads throughout the first spreader and to the bottom layer of the micro-LEDs.
In this flip-chip embodiment, light from the LED 50 is primarily emitted through the substrate 36. The second spreader 42 can be optically reflective so that light emitted from the micro-LEDs 32 in the direction of the second spreader 42 is reflected towards the LED' s substrate 36. Al or Ag is preferably used as the second spreader and each micro-LED 32 is AlGaInN based with a p-type top layer. Each top contact 40 is preferably Pt, Pt/Au, Pd, Pd/Au, Ni/Au, NiO, or NiO/Au.
This embodiment provides increased sidewall interaction with the emitted light as a result of the isolated micro-LEDs. The portion of the second spreader 42 that is disposed between the micro-LEDs functions as LEEs by reflecting light from the micro-LEDs toward the substrate. This configuration also provides improved heat transfer out of the new LED chip through the submount.
Figs. 4 and 5 show another embodiment of the new LED
51 that does not have an insulator layer to isolate the first spreader from the second. Instead, micro-LEDs 52 are connected to adjacent micro-LEDs by conductive paths 53 of an interconnected grid 54, wherein the paths have semiconductor material below them. Each opening 55 in the grid 54 is an area where semiconductor material was etched from the LED structure when manufacturing the LED
50. Portions of the structure remain under the grid 54 as micro-LEDs 52 and as semiconductor material under the grit paths 53 between the micro-LEDS. The micro-LEDs and the :nateria- under the paths comprise an active layer surrounded cy two oppositely doped layers, with the entire structure formed on a first spreader layer 56 and substrate 56.
first contact 60 is deposited on the firs t spreader to apply current to the bottom layer of the micro-LEDs and a second contact 62 is included on the current spreading grid to spread current to the top layer 10 of the micro-LEDs. When a bias is applied across the contacts 60 and 62, current is applied to the micro-LEDs and the semiconductor material under the conductive paths, all of which emit light. Light escapes from the side surfaces of the micro-LEDs material under the paths, 15 avoiding total internal reflection. This technique is therefore generally applicable to any LED structure on any substrate and is implemented with standard processing techniques.
The LED 51 is manufactured by first depositing the first spreader layer 56 on the substrate 58, and then forming a continuous LED structure that covers the current spreading layer 56. The grid 54 is deposited on the LED structure and portions of the LED structure that are visible in the grid openings are etched away by various methods such as wet chemical etching, Reactive Ion Etching (RIE) , Ion Milling, or any other technique used for removing semiconductor material. Portions of the LED structure are also etched to provide an area for contact pads 60, and contact pads 60 and 62 are deposited. The grid 54 can be made of any electrically conductive material including but not limited to metals, semi-metals, and semiconductors or combinations thereof.
The preferred micro-LEDs are GaN-based with each micro-LED's top layer 55 being a p-type AlGaInN or any allay thereof, and the grid 54 is preferably made of a thin meta' such as Ni, Pd, Au, Pt or any combination thereof.
The dashed line in FIG. 4 illustrates one of the .ml pro-LEDs and the area around the micro-LED where LEES
can be included to further enhance light extraction as more fully described below.
FIGs. 6 and 7 show two additional embodiments 70 an 80 of the, new LED with different micro-LED and grid patterns 72 and 82, although many different patterns can be used. Each embodiment has a respective bottom spreading contact 73 and 83. In FIG. 6, the micro-LEDs 74 are interconnected crosses with current spreading to each of the micro-LEDs through the various paths. Each path has semiconductor material below it to isolate it from the first spreader layer. The grid 72 provides a square array pattern of openings for light interaction.
The grid 54 has an advantage over grid 72. In LED
70, TIR light can reflect down one of the grids numerous conductive paths and reflect within the LED without interacting with a surface of one of the micro-LEDs.
Optical loss present in the grid or underlying layers will cause some of this TIR light to be absorbed before it can escape out the final edge of the new LED. The grid 54 reduces this problem because light emitting from the micro-LEDs will reach a side surface after travelling only a short distance (at most two micro-LED lengths), thereby increasing the light out of the device.
In FIG. 7 the micro-LEDs are randomly shaped and have random interconnecting paths. Again, the paths have semiconductor material below them. The random pattern reduces the number of paths for the TIR to travel before it will encounter one of the micro-LEDs in one of the 1%
grid openings. Like above, the dashed lines around the micro-LEDs in FIG. 6 and " illustrate the micro-LED 76 anc 86 with LEEs around their perimeters, as more full -v described below.
Opening sizes and distances between openings are preferably between 1 and 30 um, but may be larger or smaller. The pattern of the openings may be aperiodic or periodic since the nature of the light interaction with the micro-LED edges does not require either condition.
In the preferred embodiment on a p-type AlGaInN layer, the grid openings are between 1 micron and 20 m and the micro-LEDs have a width between 1 m and 30 pm All of the previous three embodiments can be integrated with LEEs between micro-LEDs to further increase light emission. The LEEs can either be formed on the side surfaces of the micro-LEDs or on the surface of the first spreader layer or the conductive substrate in those embodiments having no first spreader layer.
FIG. 8 shows several alternative shapes of LEEs that are included as embodiments in this invention, although other shapes can be used and the scope of this invention is not limited to the shapes shown. LEEs 82, 84, 86 have curved surfaces while the LEEs 88, 90, 92, 94 have piecewise linear surfaces. Alternatively, the LEE may be a randomly roughened layer that acts as a light disperser.
The LEEs can be formed by standard etching techniques such as wet chemical etching, RIE, or ion milling. In the preferred embodiment, the LEEs are formed by using a commercially available polymer (such as a UV
or e-beam sensitive photoresist) as an ablative etch mask. This polymer is first deposited and patterned with square-like edges. The polymer is heated to a temperature and reflows like glass to give a gradual linear or curved shape to the edges of the polymer. The polymer thickness, pattern shape, heating temperature and heating time will derermlne the edge shape. The pattern is transferred to the AlGaInN based micro-LEDs with RIE. Linear and curved LEES are easily fabricated by this method and piecewise linear LEEs can be easily formed by using multiple ablative masks.
A second technique for forming LEEs is to use a negative polarity UV-exposable photoresist. First, the photoresist is exposed for a particular exposure time and is treated to produce a negative polarity. The photoresist is then developed to produce an undercut curved or linear shape in its profile. This pattern can then be transferred to the semiconductor material through a dry etching technique. For both embodiments, the dry etching conditions will also impact the final shape of the lens in the semiconductor material.
FIGs. 9-15 show embodiments of the new LED with LEEs integrated within the micro-LED array in a variety of ways to enhance light extraction. These embodiments represent a few of the possible ways that the LEEs can be used in accordance with this invention, and the scope of this invention is not limited to the described embodiments.
FIG. 9 shows a new LED 100 that is similar to the LED 50 in Figs. 4 and 5, but has LEEs 101, 102, 103 between the micro-LEDs 104. The LEEs 101, 102, 103 allow light that is directed through a micro-LED's side surface to reflect off the LEEs and be re-directed away from the substrate into a package. Light rays that reflect off of the interface between the substrate 108 and first spreader laver 106 through TIR can. also interact with the LEES 101, 102, 103 to escape into the package, providing a higher light output. The LEEs depicted in FIG. 8 can be e:.tner deposited onto or processed into the new LED. As described above, the depth of the LEEs can also be varied with the preferred depth in the range of 0 . 5 m to 10 m..
FIG. 10 shows a new LED 110 similar to the LED 100 in FIG. 9, but having randomly roughened dispersion LEEs 112 between the micro-LEDs 113. The light interaction with the roughened layer allows TIR light to reach the surface within its critical angle and escape before being absorbed. In the preferred embodiment, the roughened surface is formed ..by using polystyrene or silica microspheres as an etch mask to transfer micro-scale roughness into the semiconductor. The depth and width of the random roughness may be less than 20nm to more that 500nm, with the preferred size being on the order of the wavelength of light generated by the LED.
FIG 11 shows a new LED 120 that is similar to LED
110 in F.G. 10, but includes a current blocking layer within the micro-LED. The blocking layer 122 directs current flow underneath the dispersive LEE 124, increasing the chance for light to interact with the LEE
and escape.
As an alternative to forming the LEEs between the micro-LEDs, the LEEs can be formed directly on the micro-LED side surfaces. FIG 12 shows a new LED 130 that is similar to the LEDs in FIGs. 9, 10 and 11, but having various LEEs 131-133 formed directly on each micro-LED' s side surfaces. The LEEs can be formed using the same methods as described above. Light that travels towards the micro-LED side surfaces is redirected in directions that cause light to escape out one of the surfaces of the substrate 134, through the first spreader layer 135, or through the micro-LEDs 132. Light that is reflected backrc7. one suostrate 134 also has an increased chance of escape -:due t the LEEs on the micro-LED edges.
T G 13 shows a new. LED 140 where curved LEEs 142 ar e formed on the side surfaces micro-LEDs 144. The curved LEEs 142 provide the additional advantage of focusing the LED light into a more well defined direction. The depth and width of the LEEs 142 can be varied with the preferred depth of any one LEE being 0.1 gm to 50 gum.
Two additional embodiments are shown in FIGs. 14 and 15. Figure 14 shows a new LED 150 with a combination o E
curved LEEs 152 on the side surface if the micro-LEDs 154 and full curved LEEs 156 between the micro-LEDs 154. The LEEs work together to enhance light extraction by refracting and reflecting light out of the LED package FIG. 15 shows new LED 160 with curved LEEs 162 on the side surfaces of the micro-LEDs 164, using flip-chip embodiment mounting similar to the embodiment shown in FIG 3. The second spreader 164 is reflective and the substrate 166 is the primary emitting surface. The LEEs 162 and the portions of the second spreader 164 work together to enhance light extraction by refracting and reflecting light out of the LED package through the substrate.
Although the present invention has been described in considerable detail with reference to certain preferred configurations thereof, other versions are possible. For instance, the bottom layers of the micro-LEDs in the array can be in contact. The light extraction structures can also be used in many different combinations and can be many different shapes and sizes. Also, the LED
structure aescribed above can have more than one active laver sandwiched between oppositely doped layers.
Therefore, the spirit and scope of the appended claims should not be limited to their preferred embodiments describes above.

Claims (38)

WHAT IS CLAIMED IS:
1. A light emitting diode (LED) with enhanced light extraction, com-prising:
a conductive first spreader layer;
a plurality of micro light emitting diodes (micro-LEDs) separately disposed on a surface of said first spreader layer, each of said micro-LEDs comprising:
a p-type layer;
an n-type layer;
an active layer sandwiched between said p-type and n-type layers wherein either said p-type or n-type layer is a top layer and the other said layer is the bottom layer, cur-rent from said first spreader layer spreading into said bottom layer;
a second spreader layer over said micro-LEDs, current from said second spreader layer spreading into said top layer, a bias applied across said first and second spreader layers causing said micro-LEDs to emit light.
2. The LED of claim 1, wherein said first spreader layer is a conduc-tive substrate.
3. The LED of claim 1, further comprising a substrate adjacent to the surface of said first spreader layer opposite said micro-LEDs.
4. The LED of claim 3, wherein said substrate is insulating and said first spreader layer is an epitaxially deposited semiconductor mate-rial.
5. The LED of claim 1, further comprising an insulating layer covering said micro-LEDs and the surface of said first spreader layer between said micro-LEDs, said insulating layer disposed between said second spreader and said micro-LEDs.
6. The LED of claim 5, wherein said insulating layer has holes over each of said micro-LEDs and said second spreader making contact with each said micro-LED through said holes.
7. The LED of claim 6, wherein said second spreader layer is a sheet of transparent conducting material.
8. The LED of claim 6, wherein said second spreader layer is an interconnected current spreading grid having a plurality of intercon-nected conductive paths, each of said micro-LEDs having one or more conductive paths over it and making contact with said top layer through said holes.
9. The LED of claim 6, wherein said second spreader is an electrically conductive material.
10. The LED of claim 1, further comprising light extraction elements (LEES) integrated with said micro-LEDs to interact with light escaping from said micro-LEDs to further enhance light extraction from said LED.
11. The LED of claim 10, wherein said LEES are disposed between said micro-LEDs.
12. The LED of claim 10, wherein said LEES are disposed on the surface of said first spreader layer, between said micro-LEDs.
13. The LED of claim 10, wherein said LEEs are integrated on the side surfaces of said micro- LEDs.
14. The LED of claim 10, wherein said LEES are integrated on the sides surfaces of said micro-LEDs and are disposed between said micro-LEDs.
15. The LED of claim 10, wherein said LEEs have curved surfaces.
16. The LED of claim 10, wherein said LEEs have linear or piecewise linear surfaces.
17. The LED of claim 10, wherein said LEES are randomly roughened surfaces.
18. The LED of claim 1, further comprising respective electrical con-tacts disposed on said first and second spreader layers, a bias applied across said contacts causing said active layer to emit light.
19. The LED of claim 6, wherein said second spreader layer is a reflec-tive metal layer that is deposited over said micro-LEDs, said LED
further comprising substrate adjacent to the surface of said first spreader opposite said micro-LEDs and a submount layer affixed to said metal layer, said substrate of said LED becoming a primary light emission surface.
20. The LED of claim 19, further comprising a conductive finger be-tween said submount and said first spreader layer, a first contact on said submount connected to said conductive finger, and a second contact on said submount connected to said metal layer, said micro-LEDs emitting light when a bias is applied across said contacts.
21. The LED of claim 1, wherein said bottom layers of said micro-LEDs are connected and said active and top layers are disconnected.
22. The LED of claim 1, wherein said second spreader layer is an interconnected current spreading grid with conductive paths between said micro-LEDs, said LED further comprising semiconductor material under said conductive paths between micro-LEDs, said semiconductor material electrically isolating said first spreader layer from said conductive paths.
23. The LED of claim 22, wherein said semiconductor material com-prises an active layer sandwiched between two oppositely doped layers.
24. A light emitting diode (LED), comprising:
a first spreader layer;
an array of light emitting elements disposed on said first spreader layer;
a second spreader layer disposed over said array of emitting ele-ments, said first spreader layer electrically isolated from said second spreader layer; and first and second contacts on said first and second spreader layer respectively, a bias applied across said contacts causing said array of emitting elements to emit light.
25. The LED of claim 24, wherein said emitting elements are micro-LEDs, each having an active layer sandwiched between two oppo-sitely doped layers.
26. The LED of claim 25, wherein said oppositely doped layers are p-and n-type layers, wherein either said p- type or n-type layer is a bottom layer adjacent to said first spreader layer and the other said layer is the top layer adjacent to said second spreader, current from said first spreader flowing into said bottom layer and current from said second spreader flowing into said top layer.
27. The LED of claim 24, further comprising a substrate adjacent to the surface of said first spreader layer opposite said emitting elements.
28. The LED of claim 24, wherein said second spreader layer is an interconnected current spreading grid covering said emitting ele-ments and having a plurality of interconnected conductive paths between said emitting elements.
29. The LED of claim 24, wherein said second spreader layer is a sheet of transparent conducting material.
30. The LED of claim 28, further comprising an insulating layer cover-ing said emitting elements and the surface of said first spreader layer between said emitting elements, said second spreader layer disposed on said insulating layer, said insulating layer electrically isolating said first spreader layer from said second spreader layer.
31. The LED of claim 30, wherein said insulating layer has holes over each of said emitting elements and said second spreader layer mak-ing contact with each said emitting element through said holes.
32. The LED of claim 31, each of said emitting elements comprising one or more conductive contacts over it, said conductive contacts making contact with said second spreader layer through said holes.
33. The LED of claim 28, further comprising semiconductor material under said conductive paths between emitting elements said semicon-ductor material electrically isolating said first spreader layer from said conductive paths.
34. The LED of claim 33, wherein said semiconductor material com-prises an active layer surrounded by two oppositely doped layers.
35. The LED of claim 24, further comprising light extraction elements between said emitting elements to redirect light emitting from said emitting elements.
36. The LED of claim 24, further comprising light extraction elements on the side surfaces of said emitting elements to redirect light emit-ting from said emitting elements.
37. A light emitting diode (LED), comprising:
a first spreader layer;

an array of micro-LEDs disposed on said first spreader layer, a current applied to said first spreader layer spreading to said micro-LEDs;
an interconnected current spreading grid disposed over said micro-LEDs, said grid having conductive paths between said micro-LEDs, a current applied to said grid spreading to said micro-LEDS;
semiconductor material under said conductive paths between micro-LEDs, said semiconductor material electrically isolating said first spreader layer from said conductive paths;
first and second contacts on said first spreader layer and said interconnected current spreading grid, respectively, a bias applied across said contacts causing said array of micro-LEDs to emit light.
38. The LED of claim 37, wherein said semiconductor material comprises an active layer sandwiched between two oppositely doped layers.
CA2393007A 1999-12-03 2000-11-20 Micro-led arrays with enhanced light extraction Expired - Lifetime CA2393007C (en)

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US09/713,576 US6410942B1 (en) 1999-12-03 2000-11-14 Enhanced light extraction through the use of micro-LED arrays
US09/713,576 2000-11-14
PCT/US2000/032084 WO2001041219A1 (en) 1999-12-03 2000-11-20 Micro-led arrays with enhanced light extraction

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110323248B (en) * 2018-03-28 2021-09-14 英属开曼群岛商镎创科技股份有限公司 Light emitting diode display panel and manufacturing method thereof

Families Citing this family (351)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001041225A2 (en) 1999-12-03 2001-06-07 Cree Lighting Company Enhanced light extraction in leds through the use of internal and external optical elements
US7547921B2 (en) * 2000-08-08 2009-06-16 Osram Opto Semiconductors Gmbh Semiconductor chip for optoelectronics
US20020017652A1 (en) * 2000-08-08 2002-02-14 Stefan Illek Semiconductor chip for optoelectronics
US7053419B1 (en) 2000-09-12 2006-05-30 Lumileds Lighting U.S., Llc Light emitting diodes with improved light extraction efficiency
US7064355B2 (en) 2000-09-12 2006-06-20 Lumileds Lighting U.S., Llc Light emitting diodes with improved light extraction efficiency
JP2002141556A (en) 2000-09-12 2002-05-17 Lumileds Lighting Us Llc Light emitting diode with improved light extraction efficiency
JP2002198560A (en) * 2000-12-26 2002-07-12 Sharp Corp Semiconductor light emitting element and its manufacturing method
US6791119B2 (en) * 2001-02-01 2004-09-14 Cree, Inc. Light emitting diodes including modifications for light extraction
JP4724924B2 (en) * 2001-02-08 2011-07-13 ソニー株式会社 Manufacturing method of display device
US6746889B1 (en) * 2001-03-27 2004-06-08 Emcore Corporation Optoelectronic device with improved light extraction
JP2002344011A (en) * 2001-05-15 2002-11-29 Sony Corp Display element and display unit using the same
US6897704B2 (en) * 2001-05-25 2005-05-24 Thunder Creative Technologies, Inc. Electronic isolator
TW583348B (en) * 2001-06-19 2004-04-11 Phoenix Prec Technology Corp A method for electroplating Ni/Au layer substrate without using electroplating wire
JP4055503B2 (en) 2001-07-24 2008-03-05 日亜化学工業株式会社 Semiconductor light emitting device
WO2003026355A2 (en) * 2001-08-30 2003-03-27 Osram Opto Semiconductors Gmbh Electroluminescent body
TW523939B (en) * 2001-11-07 2003-03-11 Nat Univ Chung Hsing High-efficient light emitting diode and its manufacturing method
US6881983B2 (en) * 2002-02-25 2005-04-19 Kopin Corporation Efficient light emitting diodes and lasers
JP3776824B2 (en) 2002-04-05 2006-05-17 株式会社東芝 Semiconductor light emitting device and manufacturing method thereof
US20030189215A1 (en) 2002-04-09 2003-10-09 Jong-Lam Lee Method of fabricating vertical structure leds
JP4585014B2 (en) * 2002-04-12 2010-11-24 ソウル セミコンダクター カンパニー リミテッド Light emitting device
JP4046118B2 (en) * 2002-05-28 2008-02-13 松下電工株式会社 LIGHT EMITTING ELEMENT, LIGHT EMITTING DEVICE USING SAME, AND SURFACE EMITTING LIGHTING DEVICE
US6841802B2 (en) * 2002-06-26 2005-01-11 Oriol, Inc. Thin film light emitting diode
US6955985B2 (en) * 2002-06-28 2005-10-18 Kopin Corporation Domain epitaxy for thin film growth
DE10234977A1 (en) * 2002-07-31 2004-02-12 Osram Opto Semiconductors Gmbh Radiation-emitting thin layer semiconductor component comprises a multiple layer structure based on gallium nitride containing an active radiation-producing layer and having a first main surface and a second main surface
US7511311B2 (en) * 2002-08-01 2009-03-31 Nichia Corporation Semiconductor light-emitting device, method for manufacturing the same, and light-emitting apparatus including the same
KR20040013998A (en) * 2002-08-09 2004-02-14 엘지전자 주식회사 Fabrication method for led of limit exterior
EP1892764B1 (en) * 2002-08-29 2016-03-09 Seoul Semiconductor Co., Ltd. Light-emitting device having light-emitting diodes
JP3956918B2 (en) 2002-10-03 2007-08-08 日亜化学工業株式会社 Light emitting diode
US7071494B2 (en) * 2002-12-11 2006-07-04 Lumileds Lighting U.S. Llc Light emitting device with enhanced optical scattering
US20060151428A1 (en) * 2002-12-30 2006-07-13 Reiner Windisch Method for roughening a surface of a body, and optoelectronic component
US7042020B2 (en) * 2003-02-14 2006-05-09 Cree, Inc. Light emitting device incorporating a luminescent material
KR100964399B1 (en) * 2003-03-08 2010-06-17 삼성전자주식회사 Semiconductor laser diode and semiconductor laser diode assembly adopting the same
US7098589B2 (en) 2003-04-15 2006-08-29 Luminus Devices, Inc. Light emitting devices with high light collimation
US7083993B2 (en) 2003-04-15 2006-08-01 Luminus Devices, Inc. Methods of making multi-layer light emitting devices
US20040259279A1 (en) 2003-04-15 2004-12-23 Erchak Alexei A. Light emitting device methods
US7262550B2 (en) * 2003-04-15 2007-08-28 Luminus Devices, Inc. Light emitting diode utilizing a physical pattern
US6831302B2 (en) 2003-04-15 2004-12-14 Luminus Devices, Inc. Light emitting devices with improved extraction efficiency
US7667238B2 (en) * 2003-04-15 2010-02-23 Luminus Devices, Inc. Light emitting devices for liquid crystal displays
US7105861B2 (en) * 2003-04-15 2006-09-12 Luminus Devices, Inc. Electronic device contact structures
US7521854B2 (en) * 2003-04-15 2009-04-21 Luminus Devices, Inc. Patterned light emitting devices and extraction efficiencies related to the same
US7274043B2 (en) * 2003-04-15 2007-09-25 Luminus Devices, Inc. Light emitting diode systems
US7074631B2 (en) * 2003-04-15 2006-07-11 Luminus Devices, Inc. Light emitting device methods
US7084434B2 (en) * 2003-04-15 2006-08-01 Luminus Devices, Inc. Uniform color phosphor-coated light-emitting diode
US7211831B2 (en) * 2003-04-15 2007-05-01 Luminus Devices, Inc. Light emitting device with patterned surfaces
US7166871B2 (en) * 2003-04-15 2007-01-23 Luminus Devices, Inc. Light emitting systems
KR101148332B1 (en) * 2003-04-30 2012-05-25 크리, 인코포레이티드 High powered light emitter packages with compact optics
US7005679B2 (en) 2003-05-01 2006-02-28 Cree, Inc. Multiple component solid state white light
DE602004028115D1 (en) * 2003-05-02 2010-08-26 Univ College Cork Nat Univ Ie LIGHT-EMITTING MESASTRUCTURES OF HIGH HEIGHT-TO-WIDE RATIO AND QUASI-PARABOLIC SIDE WALLS AND THEIR PRODUCTION
US6885034B1 (en) 2003-05-09 2005-04-26 Winston Vaughan Schoenfeld Light emitting diode having multiple pits
US7122841B2 (en) 2003-06-04 2006-10-17 Kopin Corporation Bonding pad for gallium nitride-based light-emitting devices
US20050000913A1 (en) * 2003-07-03 2005-01-06 Mark Betterly Fluid treatment system
US7009213B2 (en) 2003-07-31 2006-03-07 Lumileds Lighting U.S., Llc Light emitting devices with improved light extraction efficiency
DE60334745D1 (en) * 2003-08-08 2010-12-09 Kang Sang Kyu NITRID MICROSPHERIC EMISSION DIODE WITH GREAT BRIGHTNESS AND METHOD OF MANUFACTURING THEREOF
EP3699963A1 (en) * 2003-08-19 2020-08-26 Nichia Corporation Semiconductor light emitting diode and method of manufacturing its substrate
US7344903B2 (en) * 2003-09-17 2008-03-18 Luminus Devices, Inc. Light emitting device processes
US7341880B2 (en) * 2003-09-17 2008-03-11 Luminus Devices, Inc. Light emitting device processes
US7915085B2 (en) * 2003-09-18 2011-03-29 Cree, Inc. Molded chip fabrication method
JP4881003B2 (en) * 2003-09-26 2012-02-22 オスラム オプト セミコンダクターズ ゲゼルシャフト ミット ベシュレンクテル ハフツング Thin film semiconductor chip that emits radiation
KR101154494B1 (en) 2003-12-09 2012-06-13 재팬 사이언스 앤드 테크놀로지 에이젼시 Highly efficient group-III nitride based light emitting diodes via fabrication of structures on an N-face surface
US7450311B2 (en) * 2003-12-12 2008-11-11 Luminus Devices, Inc. Optical display systems and methods
JP2005191099A (en) * 2003-12-24 2005-07-14 ▲さん▼圓光電股▲ふん▼有限公司 Light-emitting diode device
US20050179042A1 (en) * 2004-02-13 2005-08-18 Kopin Corporation Monolithic integration and enhanced light extraction in gallium nitride-based light-emitting devices
US20050179046A1 (en) * 2004-02-13 2005-08-18 Kopin Corporation P-type electrodes in gallium nitride-based light-emitting devices
TWM271252U (en) * 2004-12-14 2005-07-21 Niching Ind Corp Package structure of light-emitting device
JP2005259891A (en) * 2004-03-10 2005-09-22 Toyoda Gosei Co Ltd Light emitting device
US7202141B2 (en) * 2004-03-29 2007-04-10 J.P. Sercel Associates, Inc. Method of separating layers of material
US7419912B2 (en) * 2004-04-01 2008-09-02 Cree, Inc. Laser patterning of light emitting devices
US7064356B2 (en) * 2004-04-16 2006-06-20 Gelcore, Llc Flip chip light emitting diode with micromesas and a conductive mesh
US7795623B2 (en) * 2004-06-30 2010-09-14 Cree, Inc. Light emitting devices having current reducing structures and methods of forming light emitting devices having current reducing structures
US7534633B2 (en) * 2004-07-02 2009-05-19 Cree, Inc. LED with substrate modifications for enhanced light extraction and method of making same
US20090023239A1 (en) * 2004-07-22 2009-01-22 Luminus Devices, Inc. Light emitting device processes
US20060038188A1 (en) * 2004-08-20 2006-02-23 Erchak Alexei A Light emitting diode systems
US20060049418A1 (en) * 2004-09-03 2006-03-09 Tzi-Chi Wen Epitaxial structure and fabrication method of nitride semiconductor device
US7259402B2 (en) * 2004-09-22 2007-08-21 Cree, Inc. High efficiency group III nitride-silicon carbide light emitting diode
US8513686B2 (en) * 2004-09-22 2013-08-20 Cree, Inc. High output small area group III nitride LEDs
US7737459B2 (en) * 2004-09-22 2010-06-15 Cree, Inc. High output group III nitride light emitting diodes
US8174037B2 (en) * 2004-09-22 2012-05-08 Cree, Inc. High efficiency group III nitride LED with lenticular surface
US7352006B2 (en) * 2004-09-28 2008-04-01 Goldeneye, Inc. Light emitting diodes exhibiting both high reflectivity and high light extraction
US20060091411A1 (en) 2004-10-29 2006-05-04 Ouderkirk Andrew J High brightness LED package
US7404756B2 (en) 2004-10-29 2008-07-29 3M Innovative Properties Company Process for manufacturing optical and semiconductor elements
US7329982B2 (en) 2004-10-29 2008-02-12 3M Innovative Properties Company LED package with non-bonded optical element
US7462502B2 (en) 2004-11-12 2008-12-09 Philips Lumileds Lighting Company, Llc Color control by alteration of wavelength converting element
US7419839B2 (en) 2004-11-12 2008-09-02 Philips Lumileds Lighting Company, Llc Bonding an optical element to a light emitting device
JP2006147679A (en) * 2004-11-17 2006-06-08 Sony Corp Integrated light emitting diode, manufacturing method thereof, display and lighting apparatus for light emitting diode
US7304363B1 (en) 2004-11-26 2007-12-04 United States Of America As Represented By The Secretary Of The Army Interacting current spreader and junction extender to increase the voltage blocked in the off state of a high power semiconductor device
US20060124943A1 (en) * 2004-12-14 2006-06-15 Elite Optoelectronics Inc. Large-sized light-emitting diodes with improved light extraction efficiency
US8288942B2 (en) 2004-12-28 2012-10-16 Cree, Inc. High efficacy white LED
JP4687109B2 (en) * 2005-01-07 2011-05-25 ソニー株式会社 Manufacturing method of integrated light emitting diode
KR101138974B1 (en) * 2005-01-07 2012-04-25 서울옵토디바이스주식회사 Luminous element and method of manufacturing thereof
US20060154393A1 (en) * 2005-01-11 2006-07-13 Doan Trung T Systems and methods for removing operating heat from a light emitting diode
US7524686B2 (en) * 2005-01-11 2009-04-28 Semileds Corporation Method of making light emitting diodes (LEDs) with improved light extraction by roughening
US7186580B2 (en) * 2005-01-11 2007-03-06 Semileds Corporation Light emitting diodes (LEDs) with improved light extraction by roughening
US20060151801A1 (en) * 2005-01-11 2006-07-13 Doan Trung T Light emitting diode with thermo-electric cooler
US7692207B2 (en) * 2005-01-21 2010-04-06 Luminus Devices, Inc. Packaging designs for LEDs
US7170100B2 (en) 2005-01-21 2007-01-30 Luminus Devices, Inc. Packaging designs for LEDs
US7335920B2 (en) * 2005-01-24 2008-02-26 Cree, Inc. LED with current confinement structure and surface roughening
KR101138944B1 (en) * 2005-01-26 2012-04-25 서울옵토디바이스주식회사 Light emitting device having a plurality of light emitting cells connected in series and method of fabricating the same
US7535028B2 (en) * 2005-02-03 2009-05-19 Ac Led Lighting, L.Lc. Micro-LED based high voltage AC/DC indicator lamp
JP2006261659A (en) * 2005-02-18 2006-09-28 Sumitomo Chemical Co Ltd Manufacturing method for semiconductor light emitting device
US7932111B2 (en) * 2005-02-23 2011-04-26 Cree, Inc. Substrate removal process for high light extraction LEDs
US20070045640A1 (en) * 2005-08-23 2007-03-01 Erchak Alexei A Light emitting devices for liquid crystal displays
US20060204865A1 (en) * 2005-03-08 2006-09-14 Luminus Devices, Inc. Patterned light-emitting devices
US8163575B2 (en) * 2005-06-17 2012-04-24 Philips Lumileds Lighting Company Llc Grown photonic crystals in semiconductor light emitting devices
KR100599012B1 (en) 2005-06-29 2006-07-12 서울옵토디바이스주식회사 Light emitting diode having a thermal conductive substrate and method of fabricating the same
US20090179211A1 (en) * 2005-07-14 2009-07-16 Tae-Kyung Yoo Light emitting device
US20070018182A1 (en) * 2005-07-20 2007-01-25 Goldeneye, Inc. Light emitting diodes with improved light extraction and reflectivity
US8674375B2 (en) * 2005-07-21 2014-03-18 Cree, Inc. Roughened high refractive index layer/LED for high light extraction
US7388233B2 (en) * 2005-10-17 2008-06-17 Luminus Devices, Inc. Patchwork patterned devices and related methods
US20070085098A1 (en) * 2005-10-17 2007-04-19 Luminus Devices, Inc. Patterned devices and related methods
US7348603B2 (en) * 2005-10-17 2008-03-25 Luminus Devices, Inc. Anisotropic collimation devices and related methods
US7391059B2 (en) 2005-10-17 2008-06-24 Luminus Devices, Inc. Isotropic collimation devices and related methods
US20080099777A1 (en) * 2005-10-19 2008-05-01 Luminus Devices, Inc. Light-emitting devices and related systems
KR100779078B1 (en) * 2005-12-09 2007-11-27 한국전자통신연구원 Silicon-based light emitting diode for enhancing light extraction efficiency and fabrication method thereof
JP4908837B2 (en) * 2005-12-13 2012-04-04 キヤノン株式会社 Light emitting element array and image forming apparatus
BRPI0620397A2 (en) 2005-12-22 2011-11-16 Cree Led Lighting Solutions lighting device
EP1974389A4 (en) 2006-01-05 2010-12-29 Illumitex Inc Separate optical device for directing light from an led
JP2007214260A (en) * 2006-02-08 2007-08-23 Matsushita Electric Ind Co Ltd Semiconductor light emitting element and its process for fabrication
KR20070088145A (en) * 2006-02-24 2007-08-29 엘지전자 주식회사 Light emitting diode and fabricating method thereof
EP2033235B1 (en) 2006-05-26 2017-06-21 Cree, Inc. Solid state light emitting device
JP2009539227A (en) 2006-05-31 2009-11-12 クリー エル イー ディー ライティング ソリューションズ インコーポレイテッド Lighting device and lighting method
KR100759896B1 (en) * 2006-06-15 2007-09-18 삼성전자주식회사 Backlight module stacked at least one luminescence element and fabrication thereof
US7674639B2 (en) * 2006-08-14 2010-03-09 Bridgelux, Inc GaN based LED with etched exposed surface for improved light extraction efficiency and method for making the same
EP2060155A2 (en) * 2006-08-23 2009-05-20 Cree Led Lighting Solutions, Inc. Lighting device and lighting method
US20100224890A1 (en) * 2006-09-18 2010-09-09 Cree, Inc. Light emitting diode chip with electrical insulation element
US7789531B2 (en) * 2006-10-02 2010-09-07 Illumitex, Inc. LED system and method
US20090275157A1 (en) * 2006-10-02 2009-11-05 Illumitex, Inc. Optical device shaping
US20080087875A1 (en) * 2006-10-11 2008-04-17 Feng-Hsu Fan Protection for the epitaxial structure of metal devices
US9318327B2 (en) 2006-11-28 2016-04-19 Cree, Inc. Semiconductor devices having low threading dislocations and improved light extraction and methods of making the same
WO2008070604A1 (en) * 2006-12-04 2008-06-12 Cree Led Lighting Solutions, Inc. Lighting device and lighting method
EP2095011A1 (en) 2006-12-04 2009-09-02 Cree Led Lighting Solutions, Inc. Lighting assembly and lighting method
US8110838B2 (en) * 2006-12-08 2012-02-07 Luminus Devices, Inc. Spatial localization of light-generating portions in LEDs
EP3223313B1 (en) 2007-01-22 2021-04-14 Cree, Inc. Monolithic light emitter having multiple light emitting sub-devices
TW200837943A (en) * 2007-01-22 2008-09-16 Led Lighting Fixtures Inc Fault tolerant light emitters, systems incorporating fault tolerant light emitters and methods of fabricating fault tolerant light emitters
US8110425B2 (en) 2007-03-20 2012-02-07 Luminus Devices, Inc. Laser liftoff structure and related methods
KR100849826B1 (en) 2007-03-29 2008-07-31 삼성전기주식회사 Light emitting device and package including the same
CN101743488B (en) * 2007-07-17 2014-02-26 科锐公司 Optical elements with internal optical features and methods of fabricating same
US8617997B2 (en) * 2007-08-21 2013-12-31 Cree, Inc. Selective wet etching of gold-tin based solder
US11114594B2 (en) * 2007-08-24 2021-09-07 Creeled, Inc. Light emitting device packages using light scattering particles of different size
US8368100B2 (en) * 2007-11-14 2013-02-05 Cree, Inc. Semiconductor light emitting diodes having reflective structures and methods of fabricating same
US9431589B2 (en) * 2007-12-14 2016-08-30 Cree, Inc. Textured encapsulant surface in LED packages
DE102008019902A1 (en) * 2007-12-21 2009-06-25 Osram Opto Semiconductors Gmbh Optoelectronic component and production method for an optoelectronic component
DE102008003182A1 (en) * 2008-01-04 2009-07-09 Osram Opto Semiconductors Gmbh Optoelectronic component
WO2009100358A1 (en) 2008-02-08 2009-08-13 Illumitex, Inc. System and method for emitter layer shaping
JP5094535B2 (en) * 2008-05-07 2012-12-12 富士フイルム株式会社 Recess formation method, uneven product manufacturing method, light emitting element manufacturing method, and optical element manufacturing method
US20090311381A1 (en) * 2008-06-11 2009-12-17 Gardner Susanne Beverages composed of wine components
US7939839B2 (en) * 2008-09-11 2011-05-10 Bridgelux, Inc. Series connected segmented LED
US7825427B2 (en) * 2008-09-12 2010-11-02 Bridgelux, Inc. Method and apparatus for generating phosphor film with textured surface
US9051177B2 (en) * 2008-10-27 2015-06-09 The United States Of America As Represented By The Secretary Of The Army Active optical limiting semiconductor device and method with active region transparent to light becoming opaque when not biased
TWI375338B (en) * 2008-11-27 2012-10-21 Epistar Corp Opto-electronic device
TW201034256A (en) 2008-12-11 2010-09-16 Illumitex Inc Systems and methods for packaging light-emitting diode devices
TWI418060B (en) * 2008-12-26 2013-12-01 Lextar Electronics Corp Method for fabricating light emitting diode chip
US7982409B2 (en) 2009-02-26 2011-07-19 Bridgelux, Inc. Light sources utilizing segmented LEDs to compensate for manufacturing variations in the light output of individual segmented LEDs
KR101134810B1 (en) 2009-03-03 2012-04-13 엘지이노텍 주식회사 Light emitting device and method for fabricating the same
JP5196403B2 (en) * 2009-03-23 2013-05-15 国立大学法人山口大学 Method for manufacturing sapphire substrate and semiconductor device
US8449128B2 (en) 2009-08-20 2013-05-28 Illumitex, Inc. System and method for a lens and phosphor layer
US8585253B2 (en) 2009-08-20 2013-11-19 Illumitex, Inc. System and method for color mixing lens array
KR20110043282A (en) * 2009-10-21 2011-04-27 엘지이노텍 주식회사 Light emitting device and method for fabricating the same
KR101039931B1 (en) * 2009-10-21 2011-06-09 엘지이노텍 주식회사 Light emitting device and method for fabricating the same
US8783915B2 (en) 2010-02-11 2014-07-22 Bridgelux, Inc. Surface-textured encapsulations for use with light emitting diodes
KR100999733B1 (en) * 2010-02-18 2010-12-08 엘지이노텍 주식회사 Light emitting device, method for fabricating the light emitting device and light emitting device package
US8338317B2 (en) 2011-04-06 2012-12-25 Infineon Technologies Ag Method for processing a semiconductor wafer or die, and particle deposition device
KR101601624B1 (en) 2010-02-19 2016-03-09 삼성전자주식회사 Semiconductor light emitting device having a multi-cell array, light emitting module and illumination apparatus
TWI485884B (en) * 2010-03-30 2015-05-21 Advanced Optoelectronic Tech Light-emitting diode and method for manufacturing the same
US8329482B2 (en) 2010-04-30 2012-12-11 Cree, Inc. White-emitting LED chips and method for making same
KR20110132136A (en) * 2010-06-01 2011-12-07 삼성전자주식회사 Light emitting device using connection structure and manufacturing method of the same
US8193546B2 (en) * 2010-06-04 2012-06-05 Pinecone Energies, Inc. Light-emitting-diode array with polymer between light emitting devices
WO2012014758A1 (en) 2010-07-26 2012-02-02 Semiconductor Energy Laboratory Co., Ltd. Light-emitting device and lighting device
US9070851B2 (en) 2010-09-24 2015-06-30 Seoul Semiconductor Co., Ltd. Wafer-level light emitting diode package and method of fabricating the same
US9899329B2 (en) 2010-11-23 2018-02-20 X-Celeprint Limited Interconnection structures and methods for transfer-printed integrated circuit elements with improved interconnection alignment tolerance
JP5589812B2 (en) 2010-12-06 2014-09-17 豊田合成株式会社 Semiconductor light emitting device
US9166126B2 (en) 2011-01-31 2015-10-20 Cree, Inc. Conformally coated light emitting devices and methods for providing the same
TWI467805B (en) * 2011-03-08 2015-01-01 Opto Tech Corp Light emitting diode having large viewing angle and method of fabricating thereof
KR101115538B1 (en) * 2011-04-04 2012-02-28 서울옵토디바이스주식회사 Luminous device and the method therefor
KR101106139B1 (en) * 2011-04-04 2012-01-20 서울옵토디바이스주식회사 Light emitting diode with a metal reflection layer expanded and method for manufacturing the same
US20120261686A1 (en) * 2011-04-12 2012-10-18 Lu Chi Wei Light-emitting element and the manufacturing method thereof
KR101737981B1 (en) 2011-05-17 2017-05-22 한국전자통신연구원 GAlIUM-NITRIDE LIGHT EMITTING DEVICE OF MICROARRAY TYPE STRUCTURE AND MANUFACTURING THEREOF
US8934259B2 (en) 2011-06-08 2015-01-13 Semprius, Inc. Substrates with transferable chiplets
KR101221336B1 (en) * 2011-07-12 2013-01-21 서울옵토디바이스주식회사 Light emitting device and method of fabricating the same
US8957440B2 (en) 2011-10-04 2015-02-17 Cree, Inc. Light emitting devices with low packaging factor
KR101901589B1 (en) * 2011-11-14 2018-09-27 엘지이노텍 주식회사 Light emitting device
US8573469B2 (en) 2011-11-18 2013-11-05 LuxVue Technology Corporation Method of forming a micro LED structure and array of micro LED structures with an electrically insulating layer
US8349116B1 (en) 2011-11-18 2013-01-08 LuxVue Technology Corporation Micro device transfer head heater assembly and method of transferring a micro device
US8809875B2 (en) 2011-11-18 2014-08-19 LuxVue Technology Corporation Micro light emitting diode
US8646505B2 (en) 2011-11-18 2014-02-11 LuxVue Technology Corporation Micro device transfer head
KR101337613B1 (en) * 2011-12-06 2013-12-06 서울바이오시스 주식회사 Luminous device and the method therefor
CA2862351A1 (en) 2012-02-02 2013-08-08 The Procter & Gamble Company Light emitting laminate and method of making thereof
US9472594B2 (en) * 2012-02-10 2016-10-18 Oculus Vr, Llc Light emitting diode chip
TWI467935B (en) * 2012-03-06 2015-01-01 Ind Tech Res Inst Visible light communication transceiver and system
GB201215632D0 (en) 2012-09-03 2012-10-17 Infiniled Ltd Optical device
JP5462333B1 (en) 2012-09-21 2014-04-02 株式会社東芝 Semiconductor light emitting device and manufacturing method thereof
DE102012109460B4 (en) * 2012-10-04 2024-03-07 OSRAM Opto Semiconductors Gesellschaft mit beschränkter Haftung Method for producing a light-emitting diode display and light-emitting diode display
CA2891250A1 (en) * 2012-11-15 2014-05-22 4233999 Canada Inc. Methods and apparatus for high speed short distance optical communications using micro light emitting diodes
US8558254B1 (en) 2012-11-29 2013-10-15 Hong Kong Applied Science and Technology Research Institute Company Limited High reliability high voltage vertical LED arrays
US9105714B2 (en) * 2012-12-11 2015-08-11 LuxVue Technology Corporation Stabilization structure including sacrificial release layer and staging bollards
US9166114B2 (en) * 2012-12-11 2015-10-20 LuxVue Technology Corporation Stabilization structure including sacrificial release layer and staging cavity
US9306138B2 (en) * 2013-04-08 2016-04-05 Xiamen Sanan Optoelectronics Technology Co., Ltd. Light emitting diode packaging structure
KR102049635B1 (en) 2013-06-12 2019-11-28 로히니, 엘엘씨. Keyboard backlighting with deposited light-generating sources
CN104241262B (en) 2013-06-14 2020-11-06 惠州科锐半导体照明有限公司 Light emitting device and display device
DE102013107967B4 (en) * 2013-07-25 2021-05-06 OSRAM Opto Semiconductors Gesellschaft mit beschränkter Haftung Optoelectronic semiconductor chip, optoelectronic component and method for producing a plurality of optoelectronic semiconductor chips
JP2014064012A (en) * 2013-10-28 2014-04-10 Toshiba Corp Semiconductor light-emitting element and method of manufacturing the same
JP6684541B2 (en) * 2014-01-20 2020-04-22 ローム株式会社 Light emitting element
DE102014009677A1 (en) * 2014-02-19 2015-08-20 Pierre-Alain Cotte Display device with improved contrast
US9231153B2 (en) * 2014-05-30 2016-01-05 Mikro Mesa Technology Co., Ltd. Micro-light-emitting diode
US9105813B1 (en) * 2014-05-30 2015-08-11 Mikro Mesa Technology Co., Ltd. Micro-light-emitting diode
EP3158583B1 (en) 2014-06-18 2022-01-26 X Display Company Technology Limited Micro assembled led displays
TWI647833B (en) 2014-08-26 2019-01-11 愛爾蘭商艾克斯瑟樂普林特有限公司 Micro-composite composite display device and light-emitting element
US9818725B2 (en) 2015-06-01 2017-11-14 X-Celeprint Limited Inorganic-light-emitter display with integrated black matrix
US9991163B2 (en) 2014-09-25 2018-06-05 X-Celeprint Limited Small-aperture-ratio display with electrical component
US9799719B2 (en) 2014-09-25 2017-10-24 X-Celeprint Limited Active-matrix touchscreen
US9799261B2 (en) 2014-09-25 2017-10-24 X-Celeprint Limited Self-compensating circuit for faulty display pixels
US9433050B2 (en) * 2014-10-08 2016-08-30 Mikro Mesa Technology Co., Ltd. Micro-light-emitting diode
US20230261153A9 (en) * 2014-10-31 2023-08-17 eLux Inc. Encapsulated Light Emitting Diodes for Selective Fluidic Assembly
US10516084B2 (en) 2014-10-31 2019-12-24 eLux, Inc. Encapsulated fluid assembly emissive elements
GB201420452D0 (en) * 2014-11-18 2014-12-31 Mled Ltd Integrated colour led micro-display
USD826871S1 (en) 2014-12-11 2018-08-28 Cree, Inc. Light emitting diode device
KR102347533B1 (en) * 2014-12-26 2022-01-05 삼성디스플레이 주식회사 Display apparatus and manufacturing method thereof
KR102175991B1 (en) 2014-12-26 2020-11-09 삼성디스플레이 주식회사 Display apparatus and manufacturing method thereof
TWI610459B (en) * 2015-05-13 2018-01-01 友達光電股份有限公司 Micro-light-emitting diode device and method for manufacturing the same
US9871345B2 (en) 2015-06-09 2018-01-16 X-Celeprint Limited Crystalline color-conversion device
CN106299095A (en) * 2015-06-12 2017-01-04 映瑞光电科技(上海)有限公司 A kind of high pressure flip LED chips and preparation method thereof
US11061276B2 (en) 2015-06-18 2021-07-13 X Display Company Technology Limited Laser array display
US10133426B2 (en) 2015-06-18 2018-11-20 X-Celeprint Limited Display with micro-LED front light
US10255834B2 (en) 2015-07-23 2019-04-09 X-Celeprint Limited Parallel redundant chiplet system for controlling display pixels
US10380930B2 (en) 2015-08-24 2019-08-13 X-Celeprint Limited Heterogeneous light emitter display system
KR102393374B1 (en) 2015-08-31 2022-05-03 삼성디스플레이 주식회사 Display apparatus and method of manufacturing the same
KR102424975B1 (en) * 2015-08-31 2022-07-26 삼성디스플레이 주식회사 Light emitting diode structure and display apparatus
USD803472S1 (en) 2015-09-03 2017-11-21 Svv Technology Innovations, Inc. Light emitting sheet with surface pattern
USD777972S1 (en) 2015-09-03 2017-01-31 Svv Technology Innovations, Inc. Light emitting sheet with surface pattern
USD829969S1 (en) 2015-09-03 2018-10-02 Svv Technology Innovations, Inc. Light emitting sheet with surface pattern
USD799738S1 (en) 2015-09-03 2017-10-10 Svv Technology Innovations, Inc. LED lighting sheet with surface pattern
US10230048B2 (en) 2015-09-29 2019-03-12 X-Celeprint Limited OLEDs for micro transfer printing
TWI576007B (en) 2015-11-23 2017-03-21 財團法人工業技術研究院 Driving method of light emitting device and light emitting device
US10066819B2 (en) 2015-12-09 2018-09-04 X-Celeprint Limited Micro-light-emitting diode backlight system
KR20220062137A (en) 2015-12-30 2022-05-13 아론 슈어파이어, 엘엘씨 Optical narrowcasting
KR102298484B1 (en) 2016-01-15 2021-09-03 로히니, 엘엘씨. Apparatus and method for backlighting through a cover on the device
TWI710061B (en) 2016-02-25 2020-11-11 愛爾蘭商艾克斯展示公司技術有限公司 Efficiently micro-transfer printing micro-scale devices onto large-format substrates
US10193025B2 (en) 2016-02-29 2019-01-29 X-Celeprint Limited Inorganic LED pixel structure
US10153256B2 (en) 2016-03-03 2018-12-11 X-Celeprint Limited Micro-transfer printable electronic component
US10153257B2 (en) 2016-03-03 2018-12-11 X-Celeprint Limited Micro-printed display
CN205944139U (en) 2016-03-30 2017-02-08 首尔伟傲世有限公司 Ultraviolet ray light -emitting diode spare and contain this emitting diode module
US10199546B2 (en) 2016-04-05 2019-02-05 X-Celeprint Limited Color-filter device
US10008483B2 (en) 2016-04-05 2018-06-26 X-Celeprint Limited Micro-transfer printed LED and color filter structure
NL2016716B1 (en) 2016-05-02 2017-11-10 Nts Systems Dev B V Exposure system, printing system, method for additive manufacturing, a composition, and the use thereof.
US9997501B2 (en) 2016-06-01 2018-06-12 X-Celeprint Limited Micro-transfer-printed light-emitting diode device
US11137641B2 (en) 2016-06-10 2021-10-05 X Display Company Technology Limited LED structure with polarized light emission
KR102608419B1 (en) * 2016-07-12 2023-12-01 삼성디스플레이 주식회사 Display Apparatus and Method for manufacturing the same
DE102016112972A1 (en) * 2016-07-14 2018-01-18 Osram Opto Semiconductors Gmbh Optoelectronic semiconductor chip
US9980341B2 (en) 2016-09-22 2018-05-22 X-Celeprint Limited Multi-LED components
US10782002B2 (en) 2016-10-28 2020-09-22 X Display Company Technology Limited LED optical components
US10347168B2 (en) 2016-11-10 2019-07-09 X-Celeprint Limited Spatially dithered high-resolution
US10395966B2 (en) 2016-11-15 2019-08-27 X-Celeprint Limited Micro-transfer-printable flip-chip structures and methods
US10600671B2 (en) 2016-11-15 2020-03-24 X-Celeprint Limited Micro-transfer-printable flip-chip structures and methods
US10224231B2 (en) 2016-11-15 2019-03-05 X-Celeprint Limited Micro-transfer-printable flip-chip structures and methods
US10193018B2 (en) * 2016-12-29 2019-01-29 Intel Corporation Compact low power head-mounted display with light emitting diodes that exhibit a desired beam angle
KR101992342B1 (en) 2017-01-26 2019-06-24 주식회사 엘지화학 Micro led and display device comprising the same
CN106935608B (en) * 2017-02-27 2019-10-25 深圳市华星光电技术有限公司 Micro- LED array substrate and display panel
US11024608B2 (en) 2017-03-28 2021-06-01 X Display Company Technology Limited Structures and methods for electrical connection of micro-devices and substrates
US9853740B1 (en) 2017-06-06 2017-12-26 Surefire Llc Adaptive communications focal plane array
DE102017114369A1 (en) * 2017-06-28 2019-01-03 Osram Opto Semiconductors Gmbh Optoelectronic component
WO2019051764A1 (en) * 2017-09-15 2019-03-21 厦门市三安光电科技有限公司 Microscopic light-emitting diode, and manufacturing method therefor
US10020422B1 (en) * 2017-09-29 2018-07-10 Oculus Vr, Llc Mesa shaped micro light emitting diode with bottom N-contact
EP3462489B1 (en) * 2017-09-29 2021-05-26 Facebook Technologies, LLC Mesa shaped micro light emitting diode with bottom n-contact
TWI641778B (en) * 2017-12-19 2018-11-21 宏碁股份有限公司 Micro lighting device
US11355548B2 (en) 2017-12-20 2022-06-07 Lumileds Llc Monolithic segmented LED array architecture
KR102428029B1 (en) 2017-12-20 2022-08-02 (주)포인트엔지니어링 Trnasfer head for micro led
US11749790B2 (en) 2017-12-20 2023-09-05 Lumileds Llc Segmented LED with embedded transistors
US11296262B2 (en) 2017-12-21 2022-04-05 Lumileds Llc Monolithic segmented LED array architecture with reduced area phosphor emission surface
US10957820B2 (en) 2017-12-21 2021-03-23 Lumileds Llc Monolithic, segmented light emitting diode array
US10879431B2 (en) 2017-12-22 2020-12-29 Lumileds Llc Wavelength converting layer patterning for LED arrays
US10418510B1 (en) 2017-12-22 2019-09-17 Facebook Technologies, Llc Mesa shaped micro light emitting diode with electroless plated N-contact
US10236986B1 (en) 2018-01-05 2019-03-19 Aron Surefire, Llc Systems and methods for tiling free space optical transmissions
KR102536305B1 (en) 2018-01-05 2023-05-24 (주)포인트엔지니어링 Micro led structure and manufactureing method of the same
US10250948B1 (en) 2018-01-05 2019-04-02 Aron Surefire, Llc Social media with optical narrowcasting
US10473439B2 (en) 2018-01-05 2019-11-12 Aron Surefire, Llc Gaming systems and methods using optical narrowcasting
KR20190114334A (en) 2018-03-29 2019-10-10 (주)포인트엔지니어링 Inspection and repair method for micro led
KR20190114330A (en) 2018-03-29 2019-10-10 (주)포인트엔지니어링 Transfer head for micro led
KR20190114333A (en) 2018-03-29 2019-10-10 (주)포인트엔지니어링 Inspection method for micro led
KR102424246B1 (en) 2018-03-30 2022-07-25 (주)포인트엔지니어링 Transfer system for micro led with transfer head
KR20190114372A (en) 2018-03-30 2019-10-10 (주)포인트엔지니어링 Transfer system for micro led
KR20190114368A (en) 2018-03-30 2019-10-10 (주)포인트엔지니어링 Micro led semi-product module
KR102481434B1 (en) 2018-03-30 2022-12-26 (주)포인트엔지니어링 Transfer head and adsorbing method for micro led using the same
KR102498037B1 (en) 2018-04-20 2023-02-10 (주)포인트엔지니어링 Micro led adsorption body
TW201944086A (en) 2018-04-06 2019-11-16 南韓商普因特工程有限公司 Micro LED adsorption body
KR102471585B1 (en) 2018-04-06 2022-11-28 (주)포인트엔지니어링 Micro led adsorption body and micro led inspection system using the same
KR20190117180A (en) 2018-04-06 2019-10-16 (주)포인트엔지니어링 Micro led adsorption body and micro led inspection system using the same
KR20190120598A (en) 2018-04-16 2019-10-24 (주)포인트엔지니어링 Micro led transfer system including micro led adsorption body
KR102471583B1 (en) 2018-04-16 2022-11-28 (주)포인트엔지니어링 Micro led transfer system including micro led adsorption body
KR102498109B1 (en) 2018-04-20 2023-02-09 (주)포인트엔지니어링 Micro led transfer system
KR20190124920A (en) 2018-04-27 2019-11-06 (주)포인트엔지니어링 Device transfer head
KR102498112B1 (en) 2018-04-27 2023-02-09 (주)포인트엔지니어링 Micro led transfer head
KR20190131311A (en) 2018-05-16 2019-11-26 (주)포인트엔지니어링 Micro led adsorption body
KR102517784B1 (en) 2018-05-16 2023-04-04 (주)포인트엔지니어링 Micro led adsorption body
KR102457191B1 (en) 2018-05-16 2022-10-20 (주)포인트엔지니어링 Micro led transfer system
KR102527138B1 (en) 2018-05-16 2023-04-28 (주)포인트엔지니어링 Micro led transfer system
KR102540859B1 (en) 2018-05-29 2023-06-07 (주)포인트엔지니어링 Transfer head for micro led and micro led transfer system using the same
KR20190135862A (en) 2018-05-29 2019-12-09 (주)포인트엔지니어링 Micro led transfer system
KR102457193B1 (en) 2018-05-29 2022-10-20 (주)포인트엔지니어링 Micro led adsorption body
KR102540860B1 (en) 2018-05-29 2023-06-07 (주)포인트엔지니어링 Transfer head for micro led and micro led transfer system using the same
CN110544661A (en) * 2018-05-29 2019-12-06 普因特工程有限公司 Micro LED transfer printing head and micro LED transfer printing system using same
KR20190136562A (en) 2018-05-31 2019-12-10 (주)포인트엔지니어링 Transfer head for micro led
KR102527139B1 (en) 2018-06-15 2023-04-28 (주)포인트엔지니어링 Transfer head for micro led and transfer stage for micro led
KR102541195B1 (en) 2018-06-27 2023-06-09 (주)포인트엔지니어링 Transfer head for micro led
CN110648956A (en) 2018-06-27 2020-01-03 普因特工程有限公司 Micro light emitting diode transfer head
KR20200005237A (en) 2018-07-06 2020-01-15 (주)포인트엔지니어링 Micro led transfer head and micro led transfer system using the same
KR20200005235A (en) 2018-07-06 2020-01-15 (주)포인트엔지니어링 Transfer head for micro led
KR20200005234A (en) 2018-07-06 2020-01-15 (주)포인트엔지니어링 Transfer head for micro led
KR20200015082A (en) 2018-08-02 2020-02-12 (주)포인트엔지니어링 Micro led structure and manufacturing method of the same
KR20200015071A (en) 2018-08-02 2020-02-12 (주)포인트엔지니어링 Transfer head for micro led
KR20200015081A (en) 2018-08-02 2020-02-12 (주)포인트엔지니어링 Micro led transfer head
KR20200015073A (en) 2018-08-02 2020-02-12 (주)포인트엔지니어링 Micro led transfer system
KR20200015076A (en) 2018-08-02 2020-02-12 (주)포인트엔지니어링 Hot air supplying head for transfering micro led and micro led transfer system using the same
EP3836234A4 (en) 2018-08-10 2022-05-04 Lin, Hong-Cheng Diode device, display panel, and flexible display
KR20200020208A (en) 2018-08-16 2020-02-26 (주)포인트엔지니어링 Micro led transfer system
KR20200020207A (en) 2018-08-16 2020-02-26 (주)포인트엔지니어링 Transfer head for micro led
KR20200025079A (en) 2018-08-29 2020-03-10 (주)포인트엔지니어링 Transfer head
US11271033B2 (en) 2018-09-27 2022-03-08 Lumileds Llc Micro light emitting devices
US10811460B2 (en) 2018-09-27 2020-10-20 Lumileds Holding B.V. Micrometer scale light emitting diode displays on patterned templates and substrates
US10923628B2 (en) 2018-09-27 2021-02-16 Lumileds Llc Micrometer scale light emitting diode displays on patterned templates and substrates
US10964845B2 (en) 2018-09-27 2021-03-30 Lumileds Llc Micro light emitting devices
KR20200053841A (en) 2018-11-09 2020-05-19 (주)포인트엔지니어링 Micro led carrier for correcting position error and micro led transfer system
KR20200085507A (en) 2019-01-07 2020-07-15 (주)포인트엔지니어링 Transfer head for micro led
KR20200095909A (en) 2019-02-01 2020-08-11 (주)포인트엔지니어링 Transfer head for micro led
KR20200099019A (en) 2019-02-13 2020-08-21 (주)포인트엔지니어링 Micro led adsorption body
KR20200129751A (en) 2019-05-10 2020-11-18 (주)포인트엔지니어링 Micro led adsorption body and manufacturing method of micro led display using the same and micro led display
KR20200135069A (en) 2019-05-24 2020-12-02 (주)포인트엔지니어링 Micro led display manufacturing and micro led display using the same
KR20200137059A (en) 2019-05-28 2020-12-09 삼성디스플레이 주식회사 Display device and manufacturing method for display device
KR20190077254A (en) * 2019-06-13 2019-07-03 엘지전자 주식회사 Lighting device using micro-led and manufacturing method thereof
KR20210006241A (en) 2019-07-08 2021-01-18 (주)포인트엔지니어링 Micro led group plate and manufacturing method thereof and micro led display panel and manufacturing method thereof
US11152534B2 (en) 2019-08-07 2021-10-19 Point Engineering Co., Ltd. Transfer head and method of manufacturing micro LED display using same
KR20210020433A (en) 2019-08-14 2021-02-24 (주)포인트엔지니어링 Micro led display manufacturing
KR20210020421A (en) 2019-08-14 2021-02-24 (주)포인트엔지니어링 Manufacturing method of micro device display
KR20210020425A (en) 2019-08-14 2021-02-24 (주)포인트엔지니어링 Transfer head for micro led
KR20210025216A (en) 2019-08-27 2021-03-09 (주)포인트엔지니어링 Micro led repair device and manufacturing of micor led display using the same
KR20210025217A (en) 2019-08-27 2021-03-09 (주)포인트엔지니어링 Micro led transfer head and manufacturing method of micro led display using the same
CN114902432A (en) * 2019-10-28 2022-08-12 加利福尼亚大学董事会 Formation of micro LED mesa structures with atomic layer deposition passivation sidewalls, self-aligned dielectric vias to top electrical contacts, and plasma damage free top contacts
KR20210063671A (en) 2019-11-25 2021-06-02 (주)포인트엔지니어링 Micro led display manufacturing
TW202135270A (en) * 2019-12-03 2021-09-16 加拿大商弗瑞爾公司 High efficient micro devices
US11674795B2 (en) 2019-12-18 2023-06-13 Lumileds Llc Miniature pattern projector using microLEDs and micro-optics
US11404473B2 (en) 2019-12-23 2022-08-02 Lumileds Llc III-nitride multi-wavelength LED arrays
US11923398B2 (en) 2019-12-23 2024-03-05 Lumileds Llc III-nitride multi-wavelength LED arrays
KR102168570B1 (en) 2020-03-03 2020-10-21 오재열 Micro LED Transfer Board
US11569415B2 (en) 2020-03-11 2023-01-31 Lumileds Llc Light emitting diode devices with defined hard mask opening
US11735695B2 (en) 2020-03-11 2023-08-22 Lumileds Llc Light emitting diode devices with current spreading layer
US11848402B2 (en) 2020-03-11 2023-12-19 Lumileds Llc Light emitting diode devices with multilayer composite film including current spreading layer
KR20220014750A (en) 2020-07-29 2022-02-07 (주)포인트엔지니어링 A apparatus for transfering micro device and alignment method using it)
KR20220021173A (en) 2020-08-13 2022-02-22 (주)포인트엔지니어링 Micro device transfer apparatus and micro device transfer system comprising the same and manufacturing method for micro device mounted on electronic products
US11626538B2 (en) 2020-10-29 2023-04-11 Lumileds Llc Light emitting diode device with tunable emission
US11901491B2 (en) 2020-10-29 2024-02-13 Lumileds Llc Light emitting diode devices
US11631786B2 (en) 2020-11-12 2023-04-18 Lumileds Llc III-nitride multi-wavelength LED arrays with etch stop layer
US11705534B2 (en) 2020-12-01 2023-07-18 Lumileds Llc Methods of making flip chip micro light emitting diodes
US11600656B2 (en) 2020-12-14 2023-03-07 Lumileds Llc Light emitting diode device

Family Cites Families (36)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5310840B2 (en) * 1972-05-04 1978-04-17
JPS50105286A (en) * 1974-01-24 1975-08-19
US3954534A (en) 1974-10-29 1976-05-04 Xerox Corporation Method of forming light emitting diode array with dome geometry
DE2926803A1 (en) 1979-07-03 1981-02-12 Licentia Gmbh ELECTROLUMINESCENCE ARRANGEMENT
FR2531814B1 (en) * 1982-08-10 1986-04-11 Thomson Csf MONOLITHIC COMBINATION OF LIGHT EMITTING DIODES AND LENSES
JPS62123785A (en) 1985-11-22 1987-06-05 Fumio Inaba Semiconductor light emitting device
JP2579931B2 (en) 1987-03-27 1997-02-12 キヤノン株式会社 Light emitting display
US4866005A (en) 1987-10-26 1989-09-12 North Carolina State University Sublimation of silicon carbide to produce large, device quality single crystals of silicon carbide
US5153889A (en) * 1989-05-31 1992-10-06 Kabushiki Kaisha Toshiba Semiconductor light emitting device
US4946547A (en) 1989-10-13 1990-08-07 Cree Research, Inc. Method of preparing silicon carbide surfaces for crystal growth
US5200022A (en) 1990-10-03 1993-04-06 Cree Research, Inc. Method of improving mechanically prepared substrate surfaces of alpha silicon carbide for deposition of beta silicon carbide thereon and resulting product
US5332910A (en) * 1991-03-22 1994-07-26 Hitachi, Ltd. Semiconductor optical device with nanowhiskers
JP2786375B2 (en) * 1992-06-18 1998-08-13 シャープ株式会社 Light emitting diode
US5309001A (en) 1991-11-25 1994-05-03 Sharp Kabushiki Kaisha Light-emitting diode having a surface electrode of a tree-like form
JP3312049B2 (en) * 1993-03-12 2002-08-05 シャープ株式会社 Semiconductor light emitting device
JP2778405B2 (en) * 1993-03-12 1998-07-23 日亜化学工業株式会社 Gallium nitride based compound semiconductor light emitting device
JP3452982B2 (en) * 1994-08-24 2003-10-06 ローム株式会社 LED print head, LED array chip, and method of manufacturing the LED array chip
JPH08139366A (en) 1994-11-11 1996-05-31 Ricoh Co Ltd Light emitting device, array-type light source, its manufacture and light signal transmitting apparatus
US5614734A (en) * 1995-03-15 1997-03-25 Yale University High efficency LED structure
DE19629920B4 (en) 1995-08-10 2006-02-02 LumiLeds Lighting, U.S., LLC, San Jose Light-emitting diode with a non-absorbing distributed Bragg reflector
DE19603444C2 (en) 1996-01-31 2003-04-24 Siemens Ag LED device with at least two LEDs
US5779924A (en) 1996-03-22 1998-07-14 Hewlett-Packard Company Ordered interface texturing for a light emitting device
US5977566A (en) * 1996-06-05 1999-11-02 Kabushiki Kaisha Toshiba Compound semiconductor light emitter
WO1997048138A2 (en) 1996-06-11 1997-12-18 Philips Electronics N.V. Visible light emitting devices including uv-light emitting diode and uv-excitable, visible light emitting phosphor, and method of producing such devices
US5708280A (en) * 1996-06-21 1998-01-13 Motorola Integrated electro-optical package and method of fabrication
US5955749A (en) * 1996-12-02 1999-09-21 Massachusetts Institute Of Technology Light emitting device utilizing a periodic dielectric structure
US5898185A (en) 1997-01-24 1999-04-27 International Business Machines Corporation Hybrid organic-inorganic semiconductor light emitting diodes
JP3752339B2 (en) * 1997-02-04 2006-03-08 ローム株式会社 Semiconductor light emitting device
JP3257455B2 (en) * 1997-07-17 2002-02-18 松下電器産業株式会社 Light emitting device
JP3505374B2 (en) * 1997-11-14 2004-03-08 三洋電機株式会社 Light emitting components
JPH11224960A (en) * 1997-11-19 1999-08-17 Unisplay Sa Led lamp and led chip
WO1999031738A2 (en) 1997-12-16 1999-06-24 Koninklijke Philips Electronics N.V. Aiii-nitride channeled led
JP3691951B2 (en) * 1998-01-14 2005-09-07 東芝電子エンジニアリング株式会社 Gallium nitride compound semiconductor light emitting device
JPH11220168A (en) * 1998-02-02 1999-08-10 Toyoda Gosei Co Ltd Gallium nitride compound semiconductor device and manufacture thereof
US6410940B1 (en) * 2000-06-15 2002-06-25 Kansas State University Research Foundation Micro-size LED and detector arrays for minidisplay, hyper-bright light emitting diodes, lighting, and UV detector and imaging sensor applications
US20020017652A1 (en) * 2000-08-08 2002-02-14 Stefan Illek Semiconductor chip for optoelectronics

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110323248B (en) * 2018-03-28 2021-09-14 英属开曼群岛商镎创科技股份有限公司 Light emitting diode display panel and manufacturing method thereof

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