CN100518421C

CN100518421C - Electroluminescence display device and method of manufacturing the same

Info

Publication number: CN100518421C
Application number: CNB2005101301295A
Authority: CN
Inventors: 宋英宇; 金润昶; 吴宗锡; 曺尚焕; 安智薰; 李濬九; 李昭玲; 河载兴
Original assignee: Samsung Mobile Display Co Ltd
Current assignee: Samsung Display Co Ltd
Priority date: 2004-12-11
Filing date: 2005-12-12
Publication date: 2009-07-22
Anticipated expiration: 2025-12-12
Also published as: KR20060066003A; KR100683734B1; CN1819727A

Abstract

An electroluminescence (EL) display device with improved external light coupling efficiency and brightness that can be easily manufactured and a method of manufacturing the EL display device are disclosed. In one embodiment, the EL display device comprises a substrate, a first electrode formed above the substrate, a second electrode formed above the first electrode and facing the first electrode, a first intermediate layer including a luminescence layer and disposed between the first and second electrodes, a color converting layer disposed on top of the second electrode and a diffraction grating disposed between the second electrode and the color converting layer.

Description

Electroluminescence display device and manufacture method thereof

The cross reference of related application

The application enjoys respectively on December 11st, 2004 and on February 19th, 2005 submitting the korean patent application No.10-2004-0104651 of Korea S Department of Intellectual Property and the priority of No.10-2005-0013889, and the full text of these two applications is incorporated in herein by reference.

Technical field

The present invention relates to electricity and cause (EL) display device and manufacture method thereof, more particularly, relate to the EL display device and the manufacture method thereof that have improved exterior light coupling efficiency and brightness and be easy to make.

Background technology

Following formula has provided the exterior light coupling efficiency η of EL display device _Ex:

η _Ex=η _Inη _OutFormula (1)

Wherein, η _InAnd η _OutRepresent the internal quantum and the output quantum efficiency of EL display device respectively.Internal quantum η _InDetermined by the disappearance situation certainly in each layer, and output quantum efficiency eta _OutCausing light to be prevented from being transmitted into extraneous situation by the total internal reflection because of each layer (is for example determined, when light when a medium with high index incides another and has medium than low-refraction, because incidence angle causes in the interface experiences total internal reflection greater than the critical angle meeting, so light can't be transferred to the external world).In the EL display device, because the light that light-emitting layer is launched will pass through a plurality of layers before being transmitted into the external world, so the refractive index difference of each layer can cause existing the light that is not launched into the external world.

When the light from luminescent layer output is transmitted into the external world, rely in the output quantum efficiency eta of the total internal reflection of interface layer _Out, that is light transmission can be expressed as:

\frac{1}{2} {(\frac{N_{out}}{N_{in}})}^{2}

Formula (2)

Wherein, N _InBe the refractive index of the layer of light institute outgoing, and N _OutIt is the refractive index of the layer of light institute incident.For example, can determine that light is about 1.5 layer by refractive index and is transferred to the output couple efficiency that refractive index is about when layer of 1.2 and is about 32% according to formula 2.That is about 70% light that enters the interface is not launched into the external world.

There is multiple trial to try hard to improve the exterior light coupling efficiency.

The open No.4-192290 of Japan Patent discloses a kind of inorganic EL equipment, wherein has a plurality ofly to have identical with inorganic EL element or larger sized optically focused microlens and be formed on the outer surface of inorganic EL element transparency carrier formed thereon.Light owing on the interface of inciding with the angle greater than critical angle between transparency carrier and the air has the incidence angle less than the critical angle on the microlens, so can be by total internal reflection.Simultaneously, thus increase brightness with predetermined direction emission light.But, because EL element is an area source in the invention of being quoted, so when utilization has or larger sized microlens identical with EL element, with diffusing of unavoidably occurring focusing on.In addition, the doubling of the image meeting that produces because of adjacent EL element reduces the definition of image.

The open No.7-037688 of Japan Patent discloses a kind of EL element that is formed on the substrate that comprises the cylindrical high index of refraction part that is made of the material with high index of refraction, and this refractive index is higher than the refractive index around material that is formed on substrate side surfaces.Partly launch to improve the exterior light coupling efficiency by high index of refraction by the light that this EL element produces.But shown in Figure 1 as quoting invention is in the invention of being quoted, by only diffusing that high index of refraction partly transmits.Therefore, how much brightness that is transmitted into the light of front do not improve.

The open No.10-172756 of Japan Patent discloses a kind of organic EL luminaire, one or more collector lens be formed on transparency carrier and form organic EL luminaire than between the low electrode.Organic EL luminaire and collector lens are set to corresponding one by one.Light by the transmission of EL luminaire incides on the interface of transparency carrier with the angle less than critical angle, thereby improves the exterior light coupling efficiency.But in the invention of being quoted, the doubling of the image meeting that is caused by adjacent EL luminaire reduces the definition of image.

Summary of the invention

One aspect of the present invention provides a kind of electroluminescence (EL) display device that has improved exterior light coupling efficiency and brightness and be easy to make, especially top emission EL display device and manufacture method thereof.

Another aspect of the present invention is the EL display device, comprising: substrate; Be formed on first electrode on this substrate; Be formed on second electrode of also facing this first electrode on this first electrode; Comprise luminescent layer and be arranged on this first electrode and this second electrode between first intermediate layer; Be arranged on the color conversion layer on this second top of electrodes; And be arranged on diffraction grating between this second electrode and this color conversion layer.

In one embodiment, this luminescent layer can be launched blue light.

In one embodiment, this color conversion layer can be converted to ruddiness, green glow or blue light with the light from this luminescent layer emission.

In one embodiment, this EL display device can further be included in and have projection on the surface in the face of this color conversion layer and be inserted in second intermediate layer between this second electrode and this color conversion layer.

In one embodiment, the space between the described projection of fills with air.

In one embodiment, the refractive index in this second intermediate layer can be higher than the refractive index of air.

In one embodiment, the refractive index refractive index materials that is lower than second intermediate layer can be filled the space between the described projection.

In one embodiment, this diffraction grating can comprise a plurality of protruding components on this second top of electrodes.

In one embodiment, air can be filled the space between the described protruding component.

In one embodiment, the refractive index of this protruding component can be higher than the refractive index of air.

In one embodiment, this diffraction grating can form by forming projection at this second electrode surface on to the surface of this color conversion layer.

In one embodiment, air can be filled the space between the described projection.

In one embodiment, described air is a nitrogen.

In one embodiment, the distance between the pattern of this diffraction grating can be from 1/4 to 4 times of this luminescent layer wavelength of light emitted.

In one embodiment, this EL display device can further be included in the lip-deep adhesion layer of this color conversion layer in the face of this diffraction grating.

Another aspect of the present invention is a kind of method of the EL of manufacturing display device.This method comprises: form first electrode on substrate; On this first electrode, form first intermediate layer that comprises luminescent layer; On this top, first intermediate layer, form second electrode; On this second top of electrodes, form diffraction grating; And on this diffraction grating top, form color conversion layer.

In one embodiment, can comprise at formation diffraction grating on this second top of electrodes: on this second top of electrodes, form second intermediate layer; And this second intermediate layer of etching away from the surface of this second electrode to form projection.

In one embodiment, be included in a plurality of protruding components of deposition on this second top of electrodes at formation diffraction grating on this second top of electrodes.

In one embodiment, on this second top of electrodes, form diffraction grating and comprise that this second electrode of etching forms projection away from the surface in this first intermediate layer.

In one embodiment, can be included in lamination color conversion layer on this diffraction grating top at formation color conversion layer on this diffraction grating top.

In one embodiment, the lamination color conversion layer carries out under nitrogen environment on this diffraction grating top.

Another aspect of the present invention provides a kind of EL display device, comprising: substrate; Be formed on first electrode on this substrate; Be formed on second electrode of also facing this first electrode on this first electrode; Comprise luminescent layer and be arranged on this first electrode and this second electrode between first intermediate layer; Be arranged on the color conversion layer between this substrate and this first electrode; And be arranged on diffraction grating between this color conversion layer and this first electrode.

In one embodiment, this luminescent layer emission blue light.

In one embodiment, this color conversion layer light that this luminescent layer can be sent is converted to ruddiness, green glow or blue light.

In one embodiment, this EL display device can further be included in and have projection on the surface in the face of this first electrode and be inserted in second intermediate layer between this first electrode and this color conversion layer.

In one embodiment, the refractive index in this second intermediate layer can be higher than be formed on this second intermediate layer or under the refractive index of layer.

In one embodiment, this EL display device can further comprise the 3rd intermediate layer that is arranged between this second intermediate layer and this first electrode, and wherein the 3rd intermediate surface is smooth to the surface of this first electrode.

In one embodiment, the 3rd intermediate layer and this first electrode can be integrated as a whole.

In one embodiment, this refractive index refractive index materials of being lower than this second intermediate layer is arranged between the described projection in this second intermediate layer.

In one embodiment, this diffraction grating can comprise a plurality of protruding components on this color conversion layer top.

In one embodiment, the refractive index of described protruding component can be higher than be formed on the described protruding component or under the refractive index of layer.

In one embodiment, this EL display device can further comprise the 3rd intermediate layer that is arranged between described protruding component and this first electrode, and wherein the 3rd intermediate surface is smooth to the surface of this first electrode.

In one embodiment, the refractive index refractive index materials that is lower than described protruding component can be arranged between the described protruding component.

In one embodiment, this diffraction grating can comprise a plurality of lip-deep projectioies that are formed on this color conversion layer in the face of this first electrode.

In one embodiment, this EL display device can further comprise the 3rd intermediate layer that is arranged between this color conversion layer and this first electrode, and wherein the 3rd intermediate surface is smooth to the surface of this first electrode.

In one embodiment, the 3rd intermediate layer and this first electrode are integrated as a whole.

In one embodiment, refractive index is lower than between the described projection that this color conversion layer refractive index materials is arranged on this color conversion layer.

Description of drawings

Below with reference to accompanying drawing embodiments of the invention are described, in these accompanying drawings:

Fig. 1 shows diffraction grating and the concept map that is changed by the caused optical path of diffraction grating;

Fig. 2 is the photo that can comprise exemplary diffraction grating in embodiments of the present invention;

Fig. 3 is the schematic cross sectional views of electroluminescence (EL) display device according to first embodiment of the invention;

Fig. 4 is the schematic cross sectional views of a distortion of EL display device shown in Figure 3;

Fig. 5 is the schematic cross sectional views of another distortion of EL display device shown in Figure 3;

Fig. 6 is the schematic cross sectional views of another distortion of EL display device shown in Figure 3;

Fig. 7 is the schematic cross sectional views according to the EL display device of second embodiment of the invention;

Fig. 8 is the schematic cross sectional views according to the EL display device of third embodiment of the invention;

Fig. 9 is the schematic cross sectional views according to the EL display device of fourth embodiment of the invention;

Figure 10 is the schematic cross sectional views according to the EL display device of fifth embodiment of the invention;

Figure 11 is the schematic cross sectional views according to the EL display device of sixth embodiment of the invention;

Figure 12 is the schematic cross sectional views according to the EL display device of seventh embodiment of the invention;

Figure 13 is the schematic cross sectional views according to the EL display device of eighth embodiment of the invention;

Figure 14 is the schematic cross sectional views according to the EL display device of ninth embodiment of the invention;

Figure 15 is the schematic cross sectional views according to the EL display device of tenth embodiment of the invention;

Figure 16 is the schematic cross sectional views according to the EL display device of eleventh embodiment of the invention;

Figure 17 is the schematic cross sectional views according to the EL display device of twelveth embodiment of the invention;

Figure 18 is the schematic cross sectional views according to the EL display device of thriteenth embodiment of the invention;

Figure 19 is the schematic cross sectional views according to the EL display device of fourteenth embodiment of the invention;

Figure 20 is the schematic cross sectional views according to the EL display device of fifteenth embodiment of the invention;

Figure 21 is the schematic cross sectional views according to the EL display device of sixteenth embodiment of the invention;

Figure 22 is the schematic cross sectional views according to the EL display device of seventeenth embodiment of the invention; With

Figure 23 is the schematic cross sectional views according to the EL display device of eighteenth embodiment of the invention.

Embodiment

Fig. 1 shows diffraction grating and the concept map that is changed by the caused optical path of diffraction grating.

As shown in Figure 1, when with angle θ _iWhen inciding light on the diffraction grating and transmitting by grating, order of diffraction k, diffraction angle _o, diffraction grating pattern the wavelength X and the refractive index n of cycle d, incident light satisfy

Nd (sin θ _i-θ _o)=k λ formula (3)

According to formula 3, can regulate diffraction angle by the cycle d that regulates diffraction grating _oFor the layer that does not have diffraction grating,, can make the light that incides this layer with angle can be adjusted to and incide this layer with angle less than critical angle greater than critical angle by comprising grating.Correspondingly, this light is launched into the external world, rather than by internal reflection.

Fig. 2 is the photo that can be included in the exemplary diffraction grating of electroluminescence (EL) display device according to the embodiment of the invention.

This grating forms the pattern such as stripe pattern.If diffraction grating forms stripe pattern, then light can not be parallel to diffraction on the direction of vitta.Therefore, if adopt the diffraction grating that forms two-dimensional arrangements shown in Figure 2, the possibility of diffraction can increase, thereby has improved the exterior light coupling efficiency.In this case, projection or the recessed different shape that adopts, for example post of circle or rectangle of diffraction grating.

Fig. 3 is the schematic cross sectional views according to the EL display device of first embodiment of the invention.

According to being used to control the luminous method of pixel, the EL display device is divided into the passive matrix type EL display device with simple matrix formula structure, and the active-matrix formula EL display device that comprises thin-film transistor (TFT).EL display device in the present embodiment is an active-matrix formula EL display device.

Referring to Fig. 3, first electrode 131 is arranged on the substrate 102, and second electrode 134 of facing first electrode 131 is arranged on first electrode 131, and comprises that first intermediate layer 133 of luminescent layer is inserted between first electrode 131 and second electrode 134.At least one TFT is connected to first electrode 131, if desired, capacitor further can be connected to TFT.

Substrate 102 can be made by clear glass, also can be made by propylene, polyamide (polymide), Merlon, polyester, mylar and other plastic material.The resilient coating (not shown) of being made by silicon dioxide can further be arranged on the substrate 102, thereby keeps substrate 102 smooth surfaces, and prevents that impurity from thrusting substrate 102.

First electrode 131 is as anode, and second electrode 134 is as negative electrode, and vice versa.

As described below, EL display device of the present invention is that light is launched the EL display device from the top that substrate 102 is launched, that is light is transmitted into second electrode 134 from first intermediate layer 133.First electrode 131 is reflecting electrodes, and second electrode 134 is transparency electrodes.This first electrode 131 can be by utilizing such as Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir or Cr, and the compound of Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir or Cr and so on forms the reflector, and forms ITO, IZO, ZnO or In in subsequently on composite structure ₂O ₃And make.First electrode 131 is corresponding to sub-pixel.Second electrode 134 can be by such as depositing Li, Ca, LiF/Ca, LiF/Al, Al or Mg on first intermediate layer 133, the perhaps compound of Li, Ca, LiF/Ca, LiF/Al, Al or Mg, and in utilizing such as ITO, IZO, ZnO or In subsequently ₂O ₃And so on be used to form transparency electrode material on composite structure, form and augment electrode layer or bus electrode line and make.Second electrode 134 perhaps is set to corresponding to whole base plate 102 corresponding to each sub-pixel.Following top emission EL display device according to other embodiments of the present invention can be set to aforesaid EL display device, perhaps framework otherwise.

As mentioned above, TFT is connected to first electrode 131.This TFT comprises semiconductor layer 122, is formed on the gate insulator 123 on semiconductor layer 122 tops, and is formed on the grid 124 on gate insulator 123 tops.Grid 124 is connected to the grid line (not shown) of gating/cut-off signals of supply TFT.The zone at grid 124 places is formed the trench region of corresponding semiconductor layer 122.The structure of TFT is not limited to shown in Figure 3, and can be arranged to the various TFT such as organic tft.

Form internal insulator 125 on the grid 124, and source electrode 126 and drain electrode 127 are connected to the source region and the drain region of semiconductor layer 122 respectively by contact hole.

By levelling blanket of such as silicon dioxide, making or protective layer 128, be formed in source electrode 126 and the drain electrode 127, and the pixel defining layer of being made by third rare, polyamide or similar material 129 is formed on the levelling blanket 128.

And although do not illustrate in the drawings, at least one capacitor is connected to TFT.The circuit that comprises TFT is not to be limited to shown in Figure 3ly, but can implement with the whole bag of tricks.

Drain electrode 127 is connected to EL element.First electrode 131 as the EL element anode is formed on the levelling blanket 128, and the pixel defining layer 129 of insulation is formed on the levelling blanket 128, and comprises that first intermediate layer 133 of luminescent layer is formed in the prodefined opening that is formed in the pixel defining layer 129.Among Fig. 3, for ease of explaining that the pattern in first intermediate layer 133 is designed to only corresponding with sub-pixel, still first intermediate layer 133 can be integrated with first intermediate layer of adjacent subpixels.

First intermediate layer 133 can be made of organic material or inorganic material.If first intermediate layer 133 is made of organic material, then this organic material can be high molecular weight organic materials or low-molecular-weight organic material.When adopting the low-molecular-weight organic material, hole injection layer (HIL), hole transmission layer (HTL), emission layer (EML), electron transfer layer (ETL), electron injecting layer (EIL) etc. can be stacked as single structure or multiplet, and organic material can be copper phthalocyanine (CuPc), N, N '-two (naphthalene-1-yl)-N, N '-diphenyl-benzidine (NPB), three-oxine aluminium (Alq3) etc.The low-molecular-weight organic material can utilize vacuum deposition method to form.

When adopting high molecular weight material, first intermediate layer 133 can comprise HTL and EML.HTL is by poly--3,4-Ethylenedioxy Thiophene (PEDOT), and EML can be by making such as high molecular weight organic materials in inferior ethene (PPV) family of polyphenylene or the poly-fluorenes family.

The structure in first intermediate layer 133 or material are applicable to following other embodiment, and the various distortion in first intermediate layer 133 also are applicable to other embodiment in the present embodiment.

The EL element that is formed on the substrate 102 is sealed by the element (not shown) in the face of this EL element.This element can be made by glass or the plastic material similar to substrate 102, but also can be made by metal cap.

Color conversion layer 111 is formed on second electrode 134, and diffraction grating is arranged between second electrode 134 and the color conversion layer 111.The diffraction grating that is included in the EL display device of present embodiment is arranged on following second intermediate layer 112.As shown in Figure 3, EL display device of the present invention is a top emission EL display device, wherein is transmitted into the external world from the light that is included in the luminescent layer in first intermediate layer 133 by second electrode 134.As shown in Figure 3, in the EL of present embodiment display device, second intermediate layer 112 and the color conversion layer 111 that only have diffraction grating to be formed on wherein are arranged on the top of second electrode 134.But if needed, the extra play except that above-mentioned can be arranged between second electrode 134 and the diffraction grating, between diffraction grating and the color conversion layer 111, the top of color conversion layer 111 is first-class.This is equally applicable to following embodiment.

Second intermediate layer 112 and color conversion layer 111 that diffraction grating is formed at wherein can be arranged on the All Ranges of EL display device as shown in Figure 3, and other structure is also feasible.For example, as shown in Figure 4, diffraction grating is positioned at wherein second intermediate layer 112 corresponding to each sub-pixel, and color conversion layer 111 is set to the All Ranges corresponding to the EL display device, perhaps as shown in Figure 5, diffraction grating be formed at wherein second intermediate layer 112 and color conversion layer 111 the two all be set to corresponding to each sub-pixel.Alternately, as shown in Figure 6, diffraction grating is formed at wherein second intermediate layer 112 and is set to All Ranges corresponding to the EL display device, and color conversion layer 111 is set to corresponding to each sub-pixel.Except that above-mentioned example, second intermediate layer 112 and color conversion layer 111 can otherwise be provided with, and are applicable to following other embodiment.

Be included in the luminescent layer emission monochromatic light in first intermediate layer 133, and the light that color conversion layer 111 is launched luminescent layer is converted to ruddiness, green glow or blue light.The luminescent layer that is included in first intermediate layer 133 can be launched such as blue light or ultraviolet ray (UV).In this case, color conversion layer 111 is converted to ruddiness or green glow with blue light, perhaps launches the blue light as original color under specific circumstances.This is applicable to following other embodiment.

Diffraction grating can be with the several different methods setting.In the EL of present embodiment display device, second intermediate layer 112 further is arranged between second electrode 134 and the color conversion layer 111, and convexes to form in second intermediate layer 112 in the face of on the surface of color conversion layer 111.The refractive index in second intermediate layer 112 is higher than air, and air can be filled diffraction grating and is formed on space 112a between the projection in second intermediate layer 112 wherein.The material of other non-air also can be filled diffraction grating and is formed on space 112a between the projection in second intermediate layer 112 wherein.If diffraction grating is formed on the refractive index of projection in second intermediate layer 112 wherein and there is difference in the refractive index of the space 112a between these projectioies, can attain the results expected so.Therefore, diffraction grating is formed on the refractive index that the refractive index in second intermediate layer 112 wherein can be higher than air and fill the air of the space 112a between these projectioies, so just can attain the results expected by simple manufacture process.Air can be a nitrogen, and it can not cause the rotten of the luminescent layer that for example is included in first intermediate layer 133.

The EL display device that has said structure for manufacturing, following process is comprised: form first electrode 131 that is positioned on the substrate 102, formation is positioned at first intermediate layer 133 that comprises luminescent layer on these first electrode, 131 tops, formation is positioned at second electrode 134 on these 133 tops, first intermediate layer, formation is positioned at the diffraction grating on these second electrode, 134 tops, and forms the color conversion layer 111 that is positioned on this diffraction grating.

Second intermediate layer 112 can further be formed between second electrode 134 and the color conversion layer 111.For the surface in the face of color conversion layer 111 that makes second intermediate layer 112 has projection, can comprise in the process that forms diffraction grating on second electrode, 134 tops: on second electrode, 134 tops, form second intermediate layer 112, and carry out etching on facing away from the surface of second electrode 134 in second intermediate layer 112, thereby the projection of formation.Forming as mentioned above after diffraction grating is formed on wherein second intermediate layer 112, be the filling of the space 112a between the projection that is formed on second intermediate layer 112 wherein at diffraction grating air, can comprise at formation color conversion layer 111 on the top in second intermediate layer 112 color conversion layer 111 is laminated on 112 tops, second intermediate layer.The process of lamination color conversion layer 111 is carried out under nitrogen environment on 112 tops, second intermediate layer, is formed on space 112a between the projection in second intermediate layer 112 wherein so that nitrogen is filled diffraction grating.And in this process, adhesion layer can be formed on color conversion layer 111 in the face of on the surface in second intermediate layer 112.When extra play was arranged between the color conversion layer 111 that diffraction grating is formed on second intermediate layer 112 wherein, extra play can be laminated on the top in second intermediate layer 112.

In said structure, be included in the light that the luminescent layer in first intermediate layer 133 launches and can be transmitted into the external world by second electrode 134, and owing to the diffraction grating that is arranged on second electrode, 134 tops has reduced the total internal reflection light quantity.That is, if do not comprise diffraction grating, be included in that luminescent layer in first intermediate layer 133 is launched, inciding the light that is formed at each layer on second electrode 134 with the angle greater than critical angle will be by total internal reflection.But by comprising diffraction grating, light can be by total internal reflection, but is transmitted into the external world by passing each layer.Therefore, by said structure, improved the exterior light coupling efficiency.

As mentioned above, by regulating the space between the diffraction grating pattern, can control refraction angle by the light of diffraction grating transmission.Therefore, the light of launching towards the front surface of EL display device is not diffracted to towards the front surface of EL display device, has therefore improved the brightness of EL display device front portion.

As shown in Equation 3, the angle of light is by the distance decision between the diffraction grating pattern.Distance between the diffraction grating pattern can be 1/4 times to 4 times from the luminescent layer wavelength of light emitted.If the distance between the diffraction grating pattern is greater than from 4 times of luminescent layer wavelength of light emitted, then the diffraction of light degree reduces, and the angle of diffraction light is not less than critical angle, and makes diffraction light by total internal reflection.On the contrary, if the distance between the diffraction grating pattern less than from 1/4 times of luminescent layer wavelength of light emitted, then therefore light seldom reduced the exterior light coupling efficiency by diffraction grating.As a result, the distance between the diffraction grating pattern can be from the luminescent layer wavelength of light emitted 1/4 times to 4 times.This also is applicable to following other embodiment.

As shown in Equation 3, the distance between the diffraction grating pattern is by determining from the emission layer wavelength of light emitted.Therefore, if from each luminescent layer wavelength of light emitted difference, the distance that then is installed between the diffraction grating pattern in each sub-pixel must change.Produce monochromatic single luminescent layer if adopt, then full-colour image will show with the light by color conversion layer 111.Therefore, the distance that is arranged between the diffraction grating pattern between luminescent layer and the color conversion layer 111 can spread all over the sub-pixel Zone Full in the same manner, simplifies manufacture process with this, reduce cost, and raising is according to the productivity ratio of the EL display device of present embodiment.

Fig. 7 is the schematic cross sectional views according to the distortion EL display device of second embodiment of the invention.

Referring to Fig. 7, first electrode 231 is formed on the substrate 202, second electrode 234 of facing first electrode 231 is arranged on first electrode 231, first intermediate layer 233 that comprises luminescent layer is arranged between first electrode 231 and second electrode 234, color conversion layer 211 is arranged on second electrode 234, and diffraction grating is arranged between second electrode 234 and the color conversion layer 211.Be included in the luminescent layer emission monochromatic light in first intermediate layer 233, and color conversion layer 211 will be converted to ruddiness, green glow or blue light from the light of luminescent layer emission.The luminescent layer that is included in first intermediate layer 233 can be launched blue light, and in this case, color conversion layer 211 is converted to ruddiness or green glow with blue light, and perhaps emission is as the blue light of original color.

As shown in Figure 7, be arranged on second electrode 234, and only have diffraction grating and color conversion layer 211 to be formed on the top of second electrode 234 according to the diffraction grating in the EL display device of present embodiment.Yet if needed, each layer can further be arranged on a plurality of positions, for example between second electrode 234 and the diffraction grating, between diffraction grating and the color conversion layer 211 and on the top of color conversion layer 211.

The EL display device of present embodiment is different.In the EL of first embodiment display device, second intermediate layer 112 of first embodiment is arranged between second electrode 134 and the color conversion layer 111, and a plurality of convexing to form in second intermediate layer 112 in the face of on the surface of color conversion layer 111, so that diffraction grating is installed.But in the EL of present embodiment display device, a plurality of protruding components 212 are formed on the top of second electrode 234, thereby form diffraction grating, simplify the EL display device manufacture process of present embodiment with this.Although as shown in Figure 7, protruding component 212 and color conversion layer 211 can form the Zone Full that spreads all over the EL display device, and protruding component 212 can be provided with in many ways, for example only corresponding to the part of EL display device.

Form the refractive index of the protruding component 212 of diffraction grating, can be higher than the refractive index that air and filling are formed on the air of the space 212a between the protruding component 212.Other material also can be filled the space 212a that is formed between the protruding component 212.But,, then can attain the results expected if the refractive index of protruding component is different from the refractive index of filling the material that is formed on the space 212a between the protruding component 212.And the refractive index of protruding component 212 can be higher than the refractive index of air, and air can be filled the space 212a that is formed between the protruding component 212, so that further simplify manufacture process.Air can be a nitrogen, and it can not cause such as being included in the rotten of luminescent layer in first intermediate layer 233.

The EL display device that has said structure for manufacturing, manufacture process comprises: form first electrode 231 that is positioned on the substrate 202, formation is positioned at first intermediate layer 233 that comprises luminescent layer on these first electrode, 231 tops, formation is positioned at second electrode 234 on these 233 tops, first intermediate layer, formation is positioned at the diffraction grating on these second electrode, 234 tops, and forms the color conversion layer 211 that is positioned on this diffraction grating top.May comprise other step between the above-mentioned steps.

Be arranged on the diffraction grating between second electrode 234 and the color conversion layer 211, form by the protruding component 212 that is positioned on these second electrode, 234 tops.Protruding component 212 can deposit formation by utilizing mask on second electrode, 234 tops, perhaps after formation second electrode 234 was with counterpart substrate 202 whole zones, the pattern that forms the diffraction grating shape by laser ablation technique (LAT) formed.

For filling air for the space 212a that is formed between the protruding component 212 that forms diffraction grating, can be after forming protruding component 212, by color conversion layer 211 being laminated on protruding component 212 tops, on the diffraction grating top, form color conversion layer 211.The process of lamination color conversion layer 211 is carried out under nitrogen environment on protruding component 212 tops, so that nitrogen is filled the space 212a that is formed between the protruding component 212.In this process, the adhesion layer (not shown) can be formed on color conversion layer 211 in the face of on the surface of protruding component 212.If extra play is formed between protruding component 212 and the color conversion layer 211, then extra play can be laminated on protruding component 212 tops.

In said structure, the luminescent layer from be included in first intermediate layer 233 seldom outputs to the light of second electrode 234, is formed on the diffraction grating total internal reflection on second electrode, 234 tops.That is, if diffraction grating is not installed, be included in then that luminescent layer in first intermediate layer 233 is launched, inciding the light that is formed on each layer on second electrode, 234 tops with the angle greater than critical angle will be by total internal reflection.But by having diffraction grating, light can be by total internal reflection, but transmission is by being formed on each layer on second electrode 234, and so is transmitted into the external world.By this structure, improved the exterior light coupling efficiency.

And, by regulating recessed distance of above-mentioned diffraction grating, can Be Controlled by the diffraction of light angle of diffraction grating.Thus, because the light of launching towards preceding screen can not be diffracted to towards preceding screen, so improved the preceding screen brightness of EL display device.

As shown in Equation 3, the distance between the diffraction grating pattern is by the wavelength of light emitted decision of luminescent layer institute.Therefore, if each luminescent layer institute wavelength of light emitted is different, recessed the distance that then is installed in the diffraction grating in each sub-pixel must change.Produce monochromatic single luminescent layer if adopt, then full-colour image will show by the light of color conversion layer 211.Therefore, the distance that is arranged on recessed of diffraction grating between luminescent layer and the color conversion layer 211 can spread all over the sub-pixel Zone Full in the same manner, simplifies manufacture process with this, reduces cost, and improves productivity ratio according to the EL display device of present embodiment.

Fig. 8 is the schematic cross sectional views according to the EL display device of third embodiment of the invention.

Referring to Fig. 8, first electrode 331 is formed on the substrate 302, second electrode 334 of facing first electrode 331 is arranged on first electrode 331, first intermediate layer 333 that comprises luminescent layer is arranged between first electrode 331 and second electrode 334, and diffraction grating is formed between second electrode 334 and the color conversion layer 311.Be included in the luminescent layer emission monochromatic light in first intermediate layer 333, color conversion layer 311 will be converted to ruddiness, green glow or blue light from the light of luminescent layer emission.The luminescent layer that is included in first intermediate layer 333 can be launched blue light, and in this case, color conversion layer 311 is converted to ruddiness or green glow with blue light, and perhaps emission is as the blue light of original color.

As shown in Figure 8, be formed on according to the diffraction grating in the EL display device of present embodiment and be arranged on second electrode 334, and only have color conversion layer 311 to be formed on second electrode, 334 tops.If needed, other layer can further be arranged on a plurality of positions, for example between second electrode 334 and the color conversion layer 311, perhaps on the top of color conversion layer 311.

Compare with the diffraction grating in the EL display device of previous embodiment, this diffraction grating is arranged on the diverse location of the EL display device of present embodiment.

In the EL of first embodiment display device, second intermediate layer 112 is arranged between second electrode 134 and the color conversion layer 111, and convexes to form in second intermediate layer 112 in the face of on the surface of color conversion layer 111, so that form diffraction grating.In the EL of second embodiment display device, thereby form diffraction grating by on the top of second electrode 234, forming protruding component 212.In the EL of present embodiment display device, diffraction grating is formed on second electrode 334 in the face of in the surface of color conversion layer 311.In the said structure, when light was transmitted into the outside by second electrode 334, the required number of interfaces of passing through of light of the emission layer emission from be included in first intermediate layer 333 was reduced.Correspondingly, be reduced, thereby improved the exterior light coupling efficiency by the light of interface total internal reflection.And by having said structure, the manufacturing of EL display device is reduced to simple more process.

The process that manufacturing has the EL display device of said structure comprises: form first electrode 331 that is positioned on the substrate 302, formation is positioned at first intermediate layer 333 that comprises luminescent layer on these first electrode, 331 tops, formation is positioned at second electrode 334 on these 333 tops, first intermediate layer, formation is positioned at the diffraction grating on these second electrode, 334 tops, and forms the color conversion layer 311 that is positioned on this diffraction grating top.May comprise other step between the above-mentioned steps.

By form a plurality of projectioies on second electrode, 334 tops, diffraction grating is set between second electrode 334 and the color conversion layer 311.For realizing this structure, second electrode 334 is faced can be etched to form projection away from the surface in first intermediate layer 333.

Fig. 9 is the schematic cross sectional views according to the EL display device of fourth embodiment of the invention.

Referring to Fig. 9, first electrode 431 is arranged on substrate 402 tops, and second electrode 434 of facing first electrode 431 is arranged on first electrode 431, and comprises that first intermediate layer 433 of luminescent layer is arranged between first electrode 431 and second electrode 434.The resilient coating (not shown) of being made by silicon dioxide can further be arranged on the substrate 402, so that keep substrate 402 smooth surfaces, and prevents that impurity from thrusting substrate 402.

Color conversion layer 411 is arranged on second electrode 434, and diffraction grating is formed between second electrode 434 and the color conversion layer 411.Diffraction grating in the EL display device of present embodiment is identical with diffraction grating in the EL display device of first embodiment.

The difference of the EL display device of present embodiment and the EL display device of first embodiment is that the EL display device of present embodiment is a passive matrix type EL display device.That is the EL display device of first embodiment comprises a TFT at least in EL element, and by controlling the light emission that each TFT controls each sub-pixel.But in the EL of present embodiment display device, the emission of the light of each sub-pixel is by being set to for example

first electrode

431 and 434 controls of second electrode of the predetermined pattern of bar paten.

Briefly, on substrate 402 tops, form first electrode 431, can make the EL element of the EL display device of present embodiment by predetermined pattern with for example bar paten.Subsequently, comprise that the intermediate layer 433 of luminescent layer and second electrode 434 can be formed on first electrode, 431 tops in succession.Insulating barrier 432 can further be formed between each of first electrode 431.Second electrode 434 can extend perpendicular to first electrode 431.And although not shown in Figure 9, independent insulating barrier can further be vertically formed with first electrode 431, thereby forms the pattern of second electrode 434.In said structure, the material in first electrode 431, second electrode 434 and intermediate layer is identical with described in the previous embodiment all.

In having the passive matrix type EL display device of said structure, second intermediate layer 412 is arranged between second electrode 434 and the color conversion layer 411, and convexes to form on 412 tops, second intermediate layer, so that form diffraction grating.Therefore, the exterior light coupling efficiency and the front luminance of EL display device have been improved.

Figure 10 and Figure 11 are the schematic cross sectional views of the EL display device of the 5th and the 6th embodiment according to the present invention.As shown in Figure 10 and Figure 11, with the EL display device of the second and the 3rd embodiment in the identical grating of diffraction grating that forms can be formed in the passive matrix type EL display device according to the embodiment of the invention.

Although what describe among the present invention first to the 6th embodiment is top emission EL display device, these embodiment be not limitation therewith, and can be used for end emission EL display device.End emission EL display device will be described below.

Figure 12 is the schematic cross sectional views according to the EL display device of seventh embodiment of the invention.

Referring to Figure 12, first electrode 731 is arranged on substrate 702 tops, and second electrode 734 of facing first electrode 731 is arranged on first electrode 731, and comprises that first intermediate layer 733 of luminescent layer is inserted between first electrode 731 and second electrode 734.At least one TFT is connected to first electrode 731, and if desired, capacitor can further be connected to TFT.

First electrode 731 is as anode, and second electrode 734 is as negative electrode, and vice versa.

The EL display device of present embodiment is that light is transmitted into extraneous end emission EL display device by substrate 702.Therefore, in the present embodiment, first electrode 731 is transparency electrodes, and second electrode 734 is reflecting electrodes.Therefore, this first electrode 731 can be by such as ITO, IZO, ZnO or In ₂O ₃And so on make.First electrode, 731 corresponding each sub-pixel.Second electrode 734 can be by for example Li, Ca, LiF/Ca, LiF/Al, Al or Mg, and perhaps the compound of Li, Ca, LiF/Ca, LiF/Al, Al or Mg is made.Second electrode 734 is corresponding to each sub-pixel, perhaps corresponding to the Zone Full of substrate 702.Following end emission EL display device has and forms the electrode identical with second electrode 734 with above-mentioned first electrode 731 of present embodiment, and perhaps they are by different frameworks.

As mentioned above, TFT is connected to first electrode 731.This TFT comprises semiconductor layer 722, is formed on the gate insulator 723 on semiconductor layer 722 tops, and is formed on the grid 724 on gate insulator 723 tops.The structure of TFT is not limited to shown in Figure 12, and the various TFT such as organic tft can both use.

Form internal insulator 725 on the grid 724, source electrode 726 and drain electrode 727 are connected to the source region and the drain region of semiconductor layer 722 respectively by contact hole.

Levelling blanket or protective layer 728 are formed on source electrode 726 and drain electrode 727 tops, and pixel defining layer 729 is formed on levelling blanket 728 tops.

Color conversion layer 711 is formed between the substrate 702 and first electrode 734, and diffraction grating is formed between the color conversion layer 711 and first electrode 731.As described below, the diffraction grating in the EL display device of present embodiment is formed on 712 tops, second intermediate layer.As shown in figure 12, the EL display device of present embodiment is an end transmitter, and the light of launching comprising the luminescent layer in first intermediate layer 733 is transmitted into the external world by substrate 702.If needed, other each layer also can further be arranged between the substrate 702 and first electrode 731.And though do not show among Figure 12, color conversion layer 711 can be formed between diffraction grating and the substrate 702 Anywhere.This also is applicable to following embodiment.

Second intermediate layer 712 or color conversion layer 711 that diffraction grating forms thereon can be arranged on the whole front surface of EL display device as shown in figure 12, but other layout of second intermediate layer 712 or color conversion layer 711 also is feasible.This also is applicable to following embodiment.

Be included in the luminescent layer emission monochromatic light in first intermediate layer 733, color conversion layer 711 is converted to ruddiness, green glow or blue light with the light of luminescent layer emission.The luminescent layer that is included in first intermediate layer 733 can be launched blue light, and in this case, color conversion layer 711 can be converted to blue light ruddiness or green glow, and perhaps emission is as the blue light of original color.

Diffraction grating can be with the several different methods setting.In the EL of present embodiment display device, second intermediate layer 712 is formed between first electrode 731 and the color conversion layer 711, and convexes to form in second intermediate layer 712 in the face of on the surface of first electrode 731.The 3rd intermediate layer 713 is formed between second intermediate layer 712 and first electrode.The 3rd intermediate layer 713 is smooth in the face of the surface of first electrode 731.In other words, by between second intermediate layer 712 and first electrode 731, forming 713, the three intermediate layers 712, the 3rd intermediate layer as levelling blanket.Need not comprise the 3rd intermediate layer 713 under some situation.

The refractive index that diffraction grating is formed on second intermediate layer 712 wherein is higher than the refractive index of the layer that is formed on 712 bottoms, second intermediate layer or top, in the hope of improved best results such as the exterior light coupling efficiency.

In the EL display device of present embodiment, owing to diffraction grating is arranged between first electrode 731 and the substrate 702, so when the luminescent layer of light from be included in first intermediate layer 733 is transmitted into the external world, reduced by the light quantity of total internal reflection.That is, if do not comprise diffraction grating, be included in that luminescent layer in first intermediate layer 733 is launched, inciding the light of each layer with the angle greater than critical angle will be by total internal reflection.When the EL display device comprised diffraction grating, light can be by total internal reflection, but is transmitted into the external world.By having said structure, improved the exterior light coupling efficiency.

And, as mentioned above,, can control refraction angle by the light of diffraction grating transmission by regulating the distance of diffraction grating between recessed.Therefore, the light of launching towards the preceding screen of EL display device is not diffracted to the preceding screen towards the EL display device, has therefore improved the preceding screen brightness of EL display device.

As shown in Equation 3, the angle of light is by the distance decision between the diffraction grating pattern.Distance between the diffraction grating pattern can be 1/4 times to 4 times from the luminescent layer wavelength of light emitted.If the distance between the diffraction grating pattern is greater than from 4 times of luminescent layer wavelength of light emitted, then the diffraction of light degree reduces, and the angle of diffraction light is not less than critical angle, and makes diffraction light by total internal reflection.On the contrary, if the distance between diffraction grating recessed less than from 1/4 times of luminescent layer wavelength of light emitted, then therefore a little light has reduced the exterior light coupling efficiency by diffraction grating.As a result, the distance between the diffraction grating pattern can be from the luminescent layer wavelength of light emitted 1/4 times to 4 times.This also is applicable to following other embodiment.

As shown in Equation 3, the distance between the diffraction grating pattern is by determining from the emission layer wavelength of light emitted.Therefore, if from each luminescent layer wavelength of light emitted difference, the distance that then is installed between the diffraction grating pattern in each sub-pixel must change.Produce monochromatic single luminescent layer if adopt, then full-colour image will show with the light by color conversion layer 711.Therefore, the distance that is arranged between the diffraction grating pattern between luminescent layer and the color conversion layer 711 can spread all over the sub-pixel Zone Full in the same manner, simplifies manufacture process with this, reduce cost, and raising is according to the productivity ratio of the EL display device of present embodiment.

Figure 13 is the schematic cross sectional views according to the EL display device of eighth embodiment of the invention.

Referring to Figure 13, first electrode 831 is arranged on the substrate 802, second electrode 834 of facing first electrode 831 is arranged on first electrode 831, first intermediate layer 833 that comprises luminescent layer is inserted between first electrode 831 and second electrode 834, color conversion layer 811 is formed between the substrate 802 and first electrode 831, and diffraction grating is formed between the color conversion layer 811 and first electrode 831.Be included in the luminescent layer emission monochromatic light in first intermediate layer 833, color conversion layer 811 is converted to ruddiness, green glow or blue light with the light of luminescent layer emission.The luminescent layer that is included in first intermediate layer 833 can be launched blue light, and in this case, color conversion layer 811 can be converted to blue light ruddiness or green glow, and perhaps emission is as the blue light of original color.

As shown in figure 13, be so-called end emission EL display device according to the EL display device of present embodiment, be transmitted into the external world comprising the light of launching in the luminescent layer in first intermediate layer 833 by substrate 802.As shown in figure 13, in the EL display device according to present embodiment, a plurality of layers are arranged between the substrate 802 and first electrode 831.If needed, also other each layer can be set further.Therefore, although not shown among Figure 13, diffraction grating can be arranged on arbitrarily between these layers.Although Figure 13 is not shown, color conversion layer 811 can be arranged between the random layer between diffraction grating and the substrate 802.

Although as shown in figure 13, diffraction grating is formed on second intermediate layer 812 or color conversion layer 811 Zone Full that is set to spread all over the EL display device wherein, and other structure is also feasible.For example, second intermediate layer 812 or color conversion layer 811 can be corresponding to each sub-pixel or each pixels.

The EL display device of present embodiment is different from the EL display device of the 7th embodiment.In the 7th embodiment, second intermediate layer 712 is arranged between first electrode 731 and the color conversion layer 711, wherein second intermediate layer 712 has formation projection thereon towards the surface of first electrode 731, and the 3rd intermediate layer 713 is arranged between second intermediate layer 712 and first electrode 731, and wherein the 3rd intermediate layer 713 is smooth towards the surface of first electrode 731.But in the EL of present embodiment display device, the 3rd intermediate layer 813 only is formed between the projection that is formed on second intermediate layer 812.By having said structure, can make more elongated EL display device.Among Figure 13, second intermediate layer 812, the 3rd intermediate layer 813 and color conversion layer 811 all are set to spread all over the Zone Full of EL display device, but other structure is also feasible.

If the refractive index in second intermediate layer 812 is higher than the refractive index in the 3rd intermediate layer 813 between the projection that is formed on second intermediate layer 812, then adopt diffraction grating can realize Expected Results.

In said structure, because diffraction grating, cause being included in being reduced that luminescent layer in first intermediate layer 833 launches by the light quantity of total internal reflection.Correspondingly, by said structure, improved the exterior light coupling efficiency.

And, as mentioned above,, can control refraction angle by the light of diffraction grating by regulating the distance of diffraction grating between recessed.Therefore, because the light of launching towards preceding screen is not diffracted to towards preceding screen, so can improve the preceding screen brightness of EL display device.

As shown in Equation 3, the distance of diffraction grating between recessed is by determining from the emission layer wavelength of light emitted.Therefore, if from each luminescent layer wavelength of light emitted difference, then being installed in diffraction grating in each sub-pixel distance between recessed must change.Produce monochromatic single luminescent layer if adopt, then full-colour image will show with the light by color conversion layer 811.Therefore, be arranged on diffraction grating between luminescent layer and the color conversion layer 811 distance between recessed and can spread all over the sub-pixel Zone Full in the same manner, simplify manufacture process, reduce cost, and improve productivity ratio according to the EL display device of present embodiment with this.

Figure 14 is the schematic cross sectional views according to the EL display device of ninth embodiment of the invention.

Referring to Figure 14, first electrode 931 is arranged on the substrate 902, second electrode 934 of facing first electrode 931 is arranged on first electrode 931, first intermediate layer 933 that comprises luminescent layer is inserted between first electrode 931 and second electrode 934, color conversion layer 911 is formed between the substrate 902 and first electrode 931, and diffraction grating is formed between the color conversion layer 911 and first electrode 931.Be included in the luminescent layer emission monochromatic light in first intermediate layer 933, color conversion layer 911 is converted to ruddiness, green glow or blue light with the light of luminescent layer emission.The luminescent layer that is included in first intermediate layer 933 can be launched blue light, and in this case, color conversion layer 911 can be converted to blue light ruddiness or green glow, and perhaps emission is as the blue light of original color.

The EL display device of present embodiment is different from the EL display device of previous embodiment.In the aforementioned embodiment, form second intermediate layer 112,412,712 and 812 of separating and be used to form diffraction grating with levelling blanket.But, in the EL of present embodiment display device, utilize the levelling blanket that is comprised in order to level and smooth TFT end face to form diffraction grating, and TFT is comprised in order to control the emission of each sub-pixel.That is in the EL of present embodiment display device, the usefulness of the levelling blanket in the previous embodiment is made in second intermediate layer 912.Second intermediate layer 912 also can be used as protective layer, to protect the TFT that forms below.Therefore, second intermediate layer 912 can be protective layer but not levelling blanket.Below, for convenience, use levelling blanket one speech.

It below is the detailed description of difference between the EL display device of the EL display device of present embodiment and previous embodiment.

Referring to Figure 14, be used for levelling blanket (second intermediate layer 912 just) level and smooth or protection TFT top and comprised, and convex to form on the surface of second intermediate layer 912 in the face of first electrode 931.The 3rd intermediate layer 913 is formed between second intermediate layer 913 and first electrode 931, and wherein the 3rd intermediate layer 913 is smooth in the face of the surface of first electrode 931.That is the 3rd intermediate layer 913 is by being included in the usefulness of making levelling blanket between second intermediate layer 912 and first electrode 931.The 3rd intermediate layer 913 is not to comprise.Be formed on second intermediate layer 912 and face the lip-deep projection of first electrode 931 only corresponding to the emitting area among Figure 14.But projection can be formed in other zone.For example, projection can form whole zone or the several pixel region that spreads all over corresponding to substrate 902.

If diffraction grating is formed on the refractive index that the refractive index in second intermediate layer 912 wherein is higher than the material between the projection that is formed on second intermediate layer 912, then adopt diffraction grating can realize for example improving the effect of exterior light coupling efficiency.

In said structure, owing to be formed on diffraction grating between first electrode 931 and the substrate 902, what cause that luminescent layer launches is reduced by the light quantity of total internal reflection.Correspondingly, by having said structure, improved the exterior light coupling efficiency.

If luminescent layer emission monochromatic light and full-colour image can be realized by the light by color conversion layer 911, then be arranged on diffraction grating between luminescent layer and the color conversion layer 911 distance between recessed and all equate in whole subpixel area.Therefore, the manufacture process of EL display device can be simplified, and the manufacturing cost of EL display device can reduce, and productivity ratio can improve.

Figure 15 is the schematic cross sectional views according to the EL display device of tenth embodiment of the invention.

The EL display device of present embodiment is different from the EL display device of the 9th embodiment.The EL display device of the 9th embodiment comprises second intermediate layer 912 as levelling blanket, wherein convex to form in second intermediate layer 912 in the face of on the surface of first electrode 931, and the 3rd intermediate layer 913 is arranged between second intermediate layer 912 and first electrode 931, and wherein the 3rd intermediate layer 913 is smooth in the face of the surface of first electrode 931.But the EL display device of present embodiment comprises only the 3rd intermediate layer 1013 between the projection that is formed on second intermediate layer 1012.By having this structure, can make elongated EL display device.The projection in second intermediate layer 1012 can only be formed on the emitting area of EL display device as shown in figure 15, and can be formed in other zone.

Figure 16 is the schematic cross sectional views according to the EL display device of eleventh embodiment of the invention.

The EL display device of present embodiment is different from the EL display device of the 9th and the tenth embodiment.The EL display device of the 9th embodiment comprises second intermediate layer 912 as levelling blanket, wherein convex to form in second intermediate layer 912 in the face of on the surface of first electrode 931, and the 3rd intermediate layer 913 is arranged between second intermediate layer 912 and first electrode 931, and wherein the 3rd intermediate layer 913 is smooth in the face of the surface of first electrode 931.The EL display device of the tenth embodiment comprises only the 3rd intermediate layer 1013 between the projection that is formed on second intermediate layer 1012.But in the present embodiment, the 3rd intermediate layer 913 or 1013 and first electrode 931 or 1031 are integrated as a whole.

It below is the detailed description of the difference between the EL display device of the EL display device of relevant present embodiment and the 9th and the tenth embodiment.

Under the EL display device situation of the 9th and the tenth embodiment, the 3rd intermediate layer 913 and 1013 covers or is inserted between the projection of second intermediate layer 912 and 1012, so that the top of the 3rd intermediate layer 913 and 1013 is level and smooth.But, in the EL of present embodiment display device, the 3rd intermediate layer 913 or 1013 and third electrode 931 or 1031 be integrated as a whole.In other words, convex to form in second intermediate layer 1112 in the face of on the surface of first electrode 1131, wherein second intermediate layer 1112 is as levelling blanket, and convex to form in first electrode 1131 between the projection that on the top in second intermediate layer 1112, forms, and be formed on 1112 tops, second intermediate layer.By having said structure, can make elongated EL display device.

The projection in second intermediate layer 1112 can only be formed in the emitting area of EL display device as shown in figure 16, perhaps can be formed in other zone, in this case, the material that forms the top in second intermediate layer 1112 has been filled the space that does not form first electrode 1131 between the projection.

Figure 17 is the schematic cross sectional views according to the EL display device of twelveth embodiment of the invention.

Referring to Figure 17, first electrode 1231 is arranged on the substrate 1202, second electrode 1234 of facing first electrode 1231 is arranged on first electrode 1231, first intermediate layer 1233 that comprises luminescent layer is inserted between first electrode 1231 and second electrode 1234, color conversion layer 1211 is formed between the substrate 1202 and first electrode 1231, and diffraction grating is formed between the color conversion layer 1211 and first electrode 1231.Be included in the luminescent layer emission monochromatic light in first intermediate layer 1233, color conversion layer 1211 is converted to ruddiness, green glow or blue light with the light of luminescent layer emission.The luminescent layer that is included in first intermediate layer 1233 can be launched blue light, and color conversion layer 1211 can be converted to blue light ruddiness or green glow, and perhaps emission is as the blue light of original color.

The EL display device of present embodiment is different from the EL display device of previous embodiment.In the aforementioned embodiment, diffraction grating is positioned at the lip-deep projection in second intermediate layer and forms by forming second intermediate layer and formation.But in the EL of present embodiment display device, diffraction grating forms by forming a plurality of protruding components 1212 that are positioned on color conversion layer 1211 tops.By having this structure, can make elongated EL display device.Protruding component 1212 or color conversion layer 1211 can be arranged on the Zone Full of EL display device as shown in figure 17, but also can differently be provided with.The 3rd intermediate layer 1213 can cover protruding component 1212, so that flat surfaces is provided.

Figure 18 is the schematic cross sectional views according to the EL display device of thriteenth embodiment of the invention.

The EL display device of present embodiment is different from the EL display device of the 12 embodiment.In the EL of the 12 embodiment display device, the 3rd intermediate layer 1213 covers the protruding component 1212 that is positioned on color conversion layer 1311 tops, so that flat surfaces is provided.But in the EL of present embodiment display device, the 3rd intermediate layer 1313 only is formed between a plurality of protruding components 1312 on color conversion layer 1311 tops, thereby flat surfaces is provided.By utilizing structure as shown in figure 18, can make elongated EL display device.Protruding component 1312 or color conversion layer 1311 can be arranged on the Zone Full of EL display device as shown in figure 18, but also can differently be provided with.

Figure 19 is the schematic cross sectional views according to the EL display device of fourteenth embodiment of the invention.

The EL display device of present embodiment is different from the EL display device of the 13 embodiment.In the EL of the 13 embodiment display device, be formed on the protruding component 1312 on color conversion layer 1311 tops, and only be formed between the protruding component 1312 so that the 3rd intermediate layer 1313 of flat surfaces to be provided, all be formed between color conversion layer 1311 and the TFT.But, in the EL of present embodiment display device, be formed on a plurality of protruding components 1412 on the color conversion layer, and only be arranged between the protruding component 1412 so that the 3rd intermediate layer 1413 of flat surfaces to be provided, be set between the TFT and first electrode 1431.Protruding component 1412 forms diffraction grating, and can be arranged on each position between the substrate 1402 and first electrode 1431.

Figure 20 is the schematic cross sectional views according to the EL display device of fifteenth embodiment of the invention.

The EL display device of present embodiment is different from the EL display device of the 6th to the 14 embodiment, first electrode 1531 is arranged between a plurality of protruding components 1512 that are formed on the color conversion layer 1511, and on the top of levelling blanket 1528 and protruding component 1512.By having this structure, can make elongated EL display device.Protruding component 1512 can still can differently be provided with corresponding to emitting area as described in Figure 20, for example spreads all over the Zone Full of EL display device.

Figure 21 is the schematic cross sectional views according to the EL display device of sixteenth embodiment of the invention.

Referring to Figure 21, first electrode 1631 is arranged on the substrate 1602, second electrode 1634 of facing first electrode 1631 is arranged on first electrode 1631, first intermediate layer 1633 that comprises luminescent layer is inserted between first electrode 1631 and second electrode 1634, color conversion layer 1611 is formed between the substrate 1602 and first electrode 1631, and diffraction grating is formed between the color conversion layer 1611 and first electrode 1631.Be included in the luminescent layer emission monochromatic light in first intermediate layer 1633, color conversion layer 1611 is converted to ruddiness, green glow or blue light with the light of luminescent layer emission.The luminescent layer that is included in first intermediate layer 1633 can be launched blue light, and in this case, color conversion layer 1611 can be converted to blue light ruddiness or green glow, and perhaps emission is as the blue light of original color.

The EL display device of present embodiment is different from the EL display device of previous embodiment.In the aforementioned embodiment, diffraction grating is positioned at the lip-deep projection in second intermediate layer and forms by forming second intermediate layer and formation, and perhaps the protruding component that is positioned on the color conversion layer top by formation forms.But in the present embodiment, diffraction grating forms in the face of the lip-deep projection of first electrode 1611 by forming a plurality of color conversion layers 1611 of being positioned at.

By having said structure, can make elongated EL display device.The projection that is formed on the color conversion layer 1611 can be as illustrated in fig. 21 corresponding to emitting area, perhaps forms to spread all over whole EL display device.

And as shown in figure 21, the 3rd intermediate layer 1613 is formed on color conversion layer 1611 tops, with as the levelling blanket that for example is formed on the TFT on 1613 tops, the 3rd intermediate layer.

Figure 22 is the schematic cross sectional views according to the EL display device of seventeenth embodiment of the invention.

The EL display device of present embodiment is different from the EL display device of the 16 embodiment.In the 16 embodiment, be formed on the 3rd intermediate layer 1613 that is used as levelling blanket on color conversion layer 1611 tops and cover whole color conversion layer 1611.But the 3rd intermediate layer 1713 of the EL display device of present embodiment only is formed between the projection that is formed on the color conversion layer 1711.

The EL display device part that the EL display device of present embodiment is different from the 16 and the 17 embodiment is, in the EL of present embodiment display device, color conversion layer 1811 is formed on levelling blanket 1828 tops, first electrode 1831 is formed on color conversion layer 1811 tops, and is formed between the projection on color conversion layer 1811 tops.

In the foregoing description some have been described active-matrix formula EL display device, and wherein at least one TFT is included in the EL display device, and the emission of each sub-pixel is by each TFT control.

But these embodiment can also be applied to the passive matrix type display device, and wherein the emission of each pixel is by first electrode that forms the predetermined pattern such as bar paten and the control of second electrode.

For example, the 18 embodiment can be applied in the EL element of following passive matrix type EL display device.First electrode 1831 is formed on substrate 1802 tops with the predetermined pattern such as bar paten.The intermediate layer 1833 and second electrode 1834 that comprise luminescent layer are formed on first electrode, 1831 tops in succession.Insulating barrier can further be formed between the bar of first electrode 1831.Second electrode 1834 can be vertical with the pattern of first electrode 1831 pattern form.And, although not shown among Figure 23, thus independently insulating barrier can be further to form with first electrode, the 1831 vertical patterns that form second electrode 1834.In said structure, the structure and material in first electrode 1831, second electrode 1834 and intermediate layer 1833 is all same as described above.

Otherwise the embodiment that describes passive matrix type EL display device also can both be applicable to active-matrix formula EL display device.

Display device and manufacture method thereof according among above-mentioned arbitrary embodiment have realized following effect.

The first, by between luminescent layer and color conversion layer, having diffraction grating, improved the preceding screen brightness of exterior light coupling efficiency and EL display device.

Second, form diffraction grating and lamination by the material that utilizes refractive index to be higher than air refraction and be formed on the layer on the diffraction grating top so that fills with air in the space between diffraction grating recessed, can more easily be made the display device with high efficiency diffraction grating.

The 3rd, diffraction grating is arranged between luminescent layer and the color conversion layer, and the light of luminescent layer emission single wavelength, so that the distance of diffraction grating between recessed can equate for all subpixel area.Therefore, the manufacture process of EL display device can be simplified, and production cost can reduce, and the productivity ratio of EL display device can improve.

Although the new feature that the present invention is applicable to each embodiment has been listed in above-mentioned narration, but one skilled in the art should appreciate that under the prerequisite that does not deviate from invention scope, can to shown in equipment or the form of process and narration make and variously delete, replace and change.Therefore, scope of the present invention is defined by the appended claims, but not aforementioned narration.Being contained in the meaning that is equal to replacement of claim and the various distortion within the scope is included within their scopes.

Claims

1, a kind of electroluminescence display device comprises:

Substrate;

Be formed on first electrode on this substrate;

Be formed on second electrode of also facing this first electrode on this first electrode;

Comprise luminescent layer and be arranged on this first electrode and this second electrode between first intermediate layer, this luminescent layer is launched monochromatic light in spreading all over the sub-pixel Zone Full;

Be arranged on the color conversion layer between this substrate and this first electrode; And

Be arranged on the diffraction grating between this color conversion layer and this first electrode,

Wherein,

This diffraction grating is formed in second intermediate layer, and this second intermediate layer is inserted between this color conversion layer and this first electrode, and has projection in the face of on the surface of this first electrode,

The refractive index in this second intermediate layer be higher than be formed on this second intermediate layer or under the refractive index of each layer,

This color conversion layer will be converted to shades of colour from emission of this luminescent layer and the monochromatic light by this diffraction grating.

2, electroluminescence display device as claimed in claim 1, wherein this luminescent layer emission blue light or ultraviolet ray.

3, electroluminescence display device as claimed in claim 1 further comprises the 3rd intermediate layer that is arranged between this second intermediate layer and this first electrode, and wherein the 3rd intermediate surface is smooth to the surface of this first electrode.

4, electroluminescence display device as claimed in claim 3, wherein the 3rd intermediate layer and this first electrode are integrated as a whole.

5, electroluminescence display device as claimed in claim 1, wherein the refractive index refractive index materials that is lower than this second intermediate layer is arranged between the described projection in this second intermediate layer.

6, electroluminescence display device as claimed in claim 1, wherein the distance between the pattern of this diffraction grating is from this luminescent layer wavelength of light emitted 1/4 to 4 times.

7, a kind of electroluminescence display device comprises:

Substrate;

Be formed on first electrode on this substrate;

Wherein,

This diffraction grating comprises a plurality of protruding components on this color conversion layer top,

The refractive index of described protruding component be higher than be formed on the described protruding component or under the refractive index of each layer,

8, electroluminescence display device as claimed in claim 7 further comprises the 3rd intermediate layer that is arranged between this protruding component and this first electrode, and wherein the 3rd intermediate surface is smooth to the surface of this first electrode.

9, electroluminescence display device as claimed in claim 8, wherein the 3rd intermediate layer and this first electrode are integrated as a whole.

10, electroluminescence display device as claimed in claim 7, wherein the refractive index refractive index materials that is lower than described protruding component is arranged between the described protruding component.

11, a kind of electroluminescence display device comprises:

Substrate;

Be formed on first electrode on this substrate;

Be arranged on the color conversion layer between this substrate and this first electrode;

Be arranged on the diffraction grating between this color conversion layer and this first electrode, this diffraction grating comprises a plurality of lip-deep projectioies that are formed on this color conversion layer in the face of this first electrode; And

Be arranged on the 3rd intermediate layer between this color conversion layer and this first electrode,

Wherein,

The 3rd intermediate surface is smooth to the surface of this first electrode,

The 3rd intermediate layer only is formed between this color conversion layer is in the face of the described projection that forms on the surface of this first electrode,

12, electroluminescence display device as claimed in claim 11, wherein the 3rd intermediate layer and this first electrode are integrated as a whole.

13, electroluminescence display device as claimed in claim 11, wherein refractive index is lower than this color conversion layer refractive index materials and is arranged between the projection of this color conversion layer.

14, a kind of electroluminescence display device comprises:

Substrate;

Be formed on first electrode on this substrate;

Be arranged on the diffraction grating between this color conversion layer and this first electrode, this diffraction grating is formed in second intermediate layer, and this second intermediate layer is inserted between this color conversion layer and this first electrode, and has projection in the face of on the surface of this first electrode; And

Be arranged on the 3rd intermediate layer between this second intermediate layer and this first electrode,

Wherein,

The 3rd intermediate surface is smooth to the surface of this first electrode,

The 3rd intermediate layer only is formed between the described projection that forms on this second intermediate layer,

15, a kind of electroluminescence display device comprises:

Substrate;

Be formed on first electrode on this substrate;

Be arranged on the diffraction grating between this color conversion layer and this first electrode, this diffraction grating comprises a plurality of protruding components on this color conversion layer top; And

Be arranged on the 3rd intermediate layer between this protruding component and this first electrode,

Wherein,

The 3rd intermediate surface is smooth to the surface of this first electrode,

The 3rd intermediate layer only is formed between the described projection that forms on this color conversion layer top,