TWI270319B - OLED display with top-emission structure - Google Patents

Abstract

An OLED display with top-emission structure includes, from bottom to top order, a substrate, a plurality of insulating regions arranged in predetermined pattern, cathode regions with trenched cross section, insulating films, OLED multi-layer and anode layer. The insulating region has a predetermined angle with respect to the substrate and the overlaid cathode has a trenched profile with the predetermined angle. The light emitted from the OLED multi-layer can be confined by the light-reflecting cathode to minimize total internal reflection. Alternatively, a transparent cathode can be placed on topmost position of the OLED device and a reflecting metal layer is provided below the anode layer to reflect the light emitted from the OLED multi-layer in order to enhance luminance efficiency.

Description

127*0319 IX. Description of the Invention: [Technical Field] The present invention relates to an organic electroluminescent display, and more particularly to an organic electroluminescent display having a top emitting structure, which can avoid the problem of total reflection to enhance upward Luminous efficiency. [Prior Art] With the popularity of portable electronic products such as cell phones, digital cameras, or personal digital assistants, the performance of flat panel displays (FPDs) is becoming increasingly important. The flat panel display mainly includes a liquid crystal display (LCD), an electric fine show if and an organic electric excitation fine turn. The eyebrow is a neon crystal display. Since the liquid crystal itself does not emit light, a backlight board needs to be added, and the weight and the volume have cost. Adverse effects. In 1987, the United States Kodak Company first published an organic light-emitting diode (OLED), injecting small organic molecules between two electrodes; afterwards, Yingguanqiao University published a polymer light-emitting diode (PLED) for nearly a decade. Due to the active research and development of each company, the materials, characteristics and related technologies of the organic light-emitting layer have made great breakthroughs. Since the organic electro-excitation display has the advantages of self-illumination, a large operating temperature range, and a wide viewing angle, it is expected to become a mainstream flat panel display. The figure shows a cross-sectional view of a conventional bottom-emitting (B〇tt〇m emissi〇n) organic light-emitting diode element 10, which mainly comprises a glass substrate view, in the glass. An anode pattern layer 12 of a predetermined pattern on the substrate 1 , an OLED light-emitting multilayer structure M 主要 mainly on the anode pattern layer 12 〇, a cathode layer 122 on the 发光 LED light-emitting layer M 、 , and an anode layer The pattern layer i2 is used as an insulating region 16 for isolation. The 发光led light-emitting multilayer structure 140 includes a bottom-up hole transport layer (HTL) 142, a light-emitting material layer (eml) i44, and an electric 1270319-sub-transport layer (ETL) 146. After a current is passed through the anode pattern layer 120 and the cathode layer 122, the electron holes are combined to emit light in the luminescent material layer (EML) 144 via the electron transport layer (ETL) 146 and the hole transport layer (HTL) 142, respectively. In order to define the pixel area and avoid the short circuit problem between the individual elements, an insulating region 160 is formed between the 1% pole pattern layers 120. However, in the above-described conventional bottom-emitting organic light-emitting diode element 10, since an active or passive driving circuit is formed on the light-emitting side (lower side), the aperture ratio of the organic light-emitting diode element 10 is affected. Figure 1 is a top view of another conventional organic light-emitting diode element 1 (NEC's Φ patent JPN 〇.10_106751) and FIG. 4 is an organic light emission in the second eight figure. The diode element 10 is along AA, a side view of the line. The organic light-emitting diode element 1 is similar to the one shown in the first figure, so that a similar metal element 180 is used on both sides of the anode pattern layer 12 to reduce the anode pattern layer 12 by using similar element numbers. The impedance of 〇. As shown in the second a diagram, the metal strips 180 are distributed in parallel strips in the organic light emitting diode element 1A. Since the anode pattern layer 120 generally uses a material having a higher work function (workfUncti〇n) to improve hole generation efficiency, such as indium tin oxide, it is possible to have a large impedance and affect luminous efficiency. The spring metal strip (10) can use a material whose work function is higher than that of the anode pattern layer to reduce the overall impedance of the anode and improve the luminous efficiency. Figure 2 is a top view of the same applicant "Yujing Technology Co., Ltd.", Republic of China Patent No. 228382 "Organic Planar Illuminated Display and Its Process", and Figure 3B shows the third A side view of the organic light-emitting diode element 1 〇 along the μ line. “The patent uses a knife-wired metal wire area around the pixel (PD ship yj), so it can inject current around the pixel area to increase luminous efficiency and make it luminously uniform. US Patent Να 5247190 reveals that the species can provide top Illumination (τ〇ρ emissi〇n) 1270319 OLED structure and material, but this patent does not provide a mechanism to solve the total reflection problem and optimize the luminous efficiency and contrast. See Figure IX, AppUedphysicsletters On April 21, 2003 (PR 2715), an organic light-emitting diode element for top emission is disclosed, which comprises a bottom-up transparent substrate 9〇1, aluminum 903. The ITO anode 905, the OLED light emitting multilayer structure 907 and the transparent cathode layer 91 do not provide a mechanism for solving the total reflection problem and optimizing the luminous efficiency and contrast. [Invention] φ The object of the invention is to provide an organic electroluminescent display having a top emission structure, which can avoid the occurrence of total reflection. The efficiency is degraded, and the purity of the light source and the efficiency of the gray scale can be increased. In order to achieve the above object of the present invention, the present invention provides an organic electroluminescent display comprising an insulating region distributed in an array from a bottom-up substrate, which is located on the substrate. And a cathode layer above the insulating region and having a well-side side, an insulating layer on the insulating region and the cathode layer, an OLED LED multilayer structure and an anode layer on the insulating layer, wherein the insulating region and the substrate have a pre- The angle between the 疋, the cathode layer formed on the insulating region has a well-shaped side of a predetermined angle. The light emitted from the OLED light-emitting multilayer structure can be reflected by the cathode layer located below the well-like side, thus having Preferably, the upward illuminating efficiency and the problem of total reflection are avoided, and the predetermined angle can be changed according to design requirements, for example, an angle of 9 。. Since the organic electroluminescent display having the top illuminating structure adopts a top emitting structure, the substrate can For any flat light-transmitting/opaque, soft/hard substrate, the organic electroluminescent portion can be directly formed into a TFT In order to increase the aperture ratio of the organic electroluminescent display, a matte polarizing film may be added to the completed illuminating element to increase the viewing angle. 8 1270319 • The above object of the invention, the invention provides an organic electric The method for fabricating an excitation light display comprises the following steps: preparing a substrate; forming a plurality of insulating regions on the substrate by a lithography process or a lithography process, wherein the insulating region and the substrate have a predetermined refreshing angle; in the insulating region Forming a cathode layer on the upper surface; forming a insulating layer on the erbium layer by a lithography process or a 郷 process; growing a QLED light-emitting layer structure on the edge layer; and forming an anode layer on the qled light-emitting layer structure. The majority of the steps of the production and the marginal zone include the application of a Pylyimide (P〇lyimide) and other materials to make a sounding process. The insulating layer step of the number of townships can also be grown by means of PVD, CVD, etc., by using an inorganic film such as oxidized stone (Si〇x), nitriding stone (fox), nitrogen oxynitride (si〇xN^, etc.). In the process of manufacturing the insulating layer, the step of manufacturing the ship layer comprises first coating a material such as polyimide, and then using an lithography process to form an insulating layer. [Embodiment] In order to enable the reviewing committee to further understand the present In order to achieve the intended purpose, the techniques, means and effects of the invention are as follows. Please refer to the following detailed description of the invention and the accompanying drawings, which are believed to be However, the drawings are provided for reference and description only, and are not intended to limit the invention. Referring to FIG. 4A, an organic electric device having high luminous efficiency and 咼 gray scale contrast according to a preferred embodiment of the present invention. The top view of the excitation light display 3 ,, the fourth b plan is a side view along the line A-A' of the fourth A picture, the organic electroluminescent display 3 〇 comprises an array of substrates 300' from bottom to top Insulated area 360 a cathode layer 322 over the substrate 3 and the insulating region 360 and having a well-side side, an insulating layer 1270319 • 350 mainly located on the insulating region 360 and the cathode layer 322, and an OLED positioned on the cathode layer 322 The light-emitting multilayer structure 340 and the anode layer 320. The insulating region and the substrate have a predetermined angle 0 such that the cathode layer formed on the insulating region has a well-shaped side with a predetermined angle. Referring to FIG. 4B, the self-turning LED The light emitted by the light-emitting multilayer structure 34 can be reflected by the cathode layer 322 having the well-side side, thereby avoiding the problem of total reflection and increasing the luminous efficiency of the organic electroluminescent display 3. The OLED light-emitting multilayer structure 340 can be Most of the color LED light-emitting multilayer structure 340 'such as red olk) light-emitting multilayer structure 3, green 〇 LED light-emitting multilayer structure m 〇 g _ and blue OLED light-emitting multilayer structure 34 〇 b, can achieve full color effect.

The cathode layer 322 having a well-side side defines a halogen light-emitting region to prevent the organic light source from escaping and losing to the surrounding area and making the light source effective side. #细不同色 When the OLED light-emitting multilayer structure is 34〇, the cathode layer cut can increase the color purity and gray-scale efficiency of the light source and increase the visibility. Furthermore, the cathode layer 322 can prevent the organic electroluminescent display 3 from being disturbed by the external light source, and can increase its resolution ability to the light source. The cathode layer is reflected from the light source, and only the light source is allowed to exit from the transparent electrode display surface such as IT〇. In the above preferred embodiment, the insulating region is made of an insulating material, and may be, for example, oxygen cut (5) (8), nitrogen cut (fox), and nitrogen oxide bangs. The cathode layer 322 can be made of a material having high conductivity and high reflectance; for example, gold, silver, quartz, chrome, or a multi-layer composite high-conductivity material. The insulating layer 350 may be a high light transmissive material such as yttrium oxide = SiNx or SiOX (Si0xNy), and the thickness may be 〇 〇. : The anode layer 32A may be a transparent electrode _ such as ΙΤΟ, ιζο or IW0. Since the organic electroluminescent display 3 of the present invention is an 11-turn configuration, the base 1270319_plate 300 can be any flat light-transmitting/opaque, soft/hard substrate. The organic electroluminescent display ϋ 30 of the present invention can be directly formed on a thin film transistor (TFT) to help increase the aperture ratio. Moreover, since the bottom cathode layer 322 is torn by the upper OLED light emitting multilayer structure and protected by the anode layer 320, it contributes to prolonging the life of the element. Referring to Figures 5A through 5, a method of fabricating an organic electroluminescent portion 30 according to the preferred embodiment of the present invention comprises the following steps:

Step S500: Preparing a substrate 300, for example, a glass substrate 3, in which Φ also cleans the glass substrate with a liquid such as detergent or deionized water (Fig. AA).

Step S510: A plurality of insulating regions 36 are formed on the substrate 300. For example, a material such as polyimide may be coated first, and a lithography process may be used to make an insulating region tear or grow Si in a PVD or CVD manner. x, ship, (10) chat and other inorganic membranes, and then use the micro-engraving process to make the insulation zone 360 (fifth B).

Step S520: The cathode layer 322 is formed on the substrate 300 and the insulating region 36, and the metal cathode layer 322 pattern can be formed by sputtering, electroplating, electron beam or f-plating to form a metal cathode layer 322 pattern (the fifth layer: ).

StepS5; 30 - The insulating layer 35 is formed on the cathode layer 322, and a material such as polydendamine (Pdyimide) can be applied first, and then an insulating layer 35 can be formed by a lithography process, or ρν〇, CVD, or the like can be used. The method is to grow inorganic materials such as Si〇x, fox, si〇xNy and the like, and the thickness is about 〇·5 5μιη 'reuse the lithography process to make the insulating layer 35〇 (fifth map).

Step S540: A 发光led light-emitting multilayer structure 34 is formed on the cathode layer 322 and the insulating layer 35, and for example, the LED light-emitting multilayer structure (10) can be grown by vapor deposition (fifth E diagram). 11 1270319 • StepS55〇: An anode layer 32〇 is formed on the 〇LED light-emitting multilayer structure 340, and a transparent electrode film such as ITO, IZO or IWO can be grown by a shovel, steaming and electron beam special method (fifth F). Referring to FIG. 3, wherein the insulating region has a predetermined angle 0 with the substrate, such that the cathode layer formed on the insulating region has a well-shaped side with a predetermined angle, and the predetermined angle may vary depending on design requirements, for example, Can be at an angle of 90 degrees to effectively reduce total reflection. Further, a matte polarizing film (not shown) may be added to the finally formed light-emitting element to increase the viewing angle. The luminescent element formed by the final Φ is referred to herein as the anode layer 320. Figure 7 is a diagram showing an organic electroluminescent display 30' having a top emission structure in accordance with another preferred embodiment of the present invention. As shown in FIG. 7 , the organic electroluminescent display 3 has an insulating region 360 ′ which is distributed in an array from the bottom to the top substrate 3′′, and a reflective metal layer 370 located on the insulating region 360. The anode layer 320, which is disposed on the reflective metal layer 370 and arranged in an array, is disposed on the anode layer 320 and is mainly distributed on the insulating region 36〇. The insulating layer 350', located on the anode layer 32A, and the insulating layer 350, has a 〇LED light-emitting multilayer structure 34〇, which is associated with the transparent cathode 322 over the entire structure. Further, a matte polarizing film (not shown) may be added to the cathode layer 322 to increase the viewing angle. The reflective metal layer 370 is made of a metal material having a south reflectance, and for example, a metal material such as silver may be used. The transparent cathode 322 can be made of a metal material having high permeability, and for example, a metal material such as aluminum or silver can be used. The substrate 3, the insulating region 36, the anode layer 32〇f, the insulating layer 350', and the 发光led light-emitting multilayer structure 340' may be made of a material similar to that of the corresponding element shown in the fourth b-picture. 12 1270319 Referring to Figures 8A to 8g, a flow chart of an organic electroluminescent display. According to this (4) - difficult ship example

Stq>S_.Preparation-substrate', for example, may be a glass substrate. In this step, the glass substrate is also cleaned with a liquid such as a detergent or deionized water (Fig. 8A). _ (4): On the substrate 3 (8)' to make a majority of the insulation zone, for example, you can first coat the characteristics of Polyaluminium.) Then use the lithography process to make the insulation zone sigh or use the soil PVD, CVD method to grow coffee, Chi, move y, etc. The inorganic film is further fabricated into an insulating region 360, (eighth b).

Step S82G : _ job, inspection, electron beam or Wei (four) process metal film and then use the lithography process to make a reflective metal layer 37 cap case, the material can be silver or other highly reflective metal material (eighth c picture) .

StepS830 ··The anode layer 32〇 is formed on the reflective metal layer treasure, and the electrode thief such as IT0, IZ〇 or circle can be grown by splashing, vapor deposition and electronic materials, and then the anode layer 320 is fabricated by using a photolithography etching process. , (eighth D picture).

Step S840 ·• The insulating layer 35〇 is formed on the anode layer 320', and the material such as polyimide or the like may be applied first, and then the insulating layer 35 制作 may be formed by using a lithography process; or the pvD, CVD may be used. The inorganic film such as Si0x, SiNx, and Si〇xNy is grown to have a thickness of about 0.5 to 5 μm, and an insulating layer 35 is formed by a photolithography process (Eth 8th).

Step S850: An OLED light emitting multilayer structure 340' is formed on the anode layer 320' and the insulating layer 350. For example, the OLED light emitting multilayer structure 34A can be grown by vapor deposition (Fig. 8F).

Step S860 · Making a transparent cathode 322 on the OLED light-emitting multilayer structure 340', sinking 13 1270319

Metal film: _, evaporation, electronic growth, permeable, transparent metal film, production through 32_, Butterfly Wit is the eighth G map). At the job, the present invention can provide a design that is different from the prior art by the above-mentioned disclosed technology, which can improve the overall use value, and is not found in the publication or public use before the application, and has already complied with the invention patent. The essentials are to file an invention patent application in accordance with the law. The drawings and descriptions of the above-mentioned disclosed roads are only examples of the present invention, and those skilled in the art can make other improvements according to the above description, and these changes still belong to the inventive spirit of the present invention. And in the scope of patents defined below. BRIEF DESCRIPTION OF THE DRAWINGS The figure is a side view of a conventional Bottom emission organic light emitting diode element. The first A is not a top view of another conventional organic light emitting diode element.

The second panel is shown in the side view along the second A-line A-A. The second Figure A is a top view of another conventional organic light emitting diode element. The figure shown in the third B is a side view along the third A line Λ-A. Figure 4A is a top view of an organic electroluminescent display in accordance with a preferred embodiment of the present invention. The figure shown in the fourth B is a side view along the fourth A line A-A. Figs. 5A to 5F are diagrams showing a method of fabricating an organic electroluminescent portion according to a preferred embodiment of the present invention. 14 1270319 $ Figure 6 is a side elevational view of an organic electroluminescent display in accordance with another preferred embodiment of the present invention. The seventh figure is not an organic electroluminescent display having a top emission structure according to another preferred embodiment of the present invention. The eighth to third figures G are flowcharts for fabricating an organic electroluminescent display in accordance with another preferred embodiment of the present invention. _ The figure shown in the ninth figure is a side view of another conventional organic light emitting diode element. [Main component symbol description] [Prior art] 10 organic light emitting diode element 100 glass substrate 120 anode pattern layer 122 cathode layer 140 OLED light emitting multilayer structure 142 hole transport layer H4 light emitting material layer 146 electron transport layer 160 insulating region 180 Metal strip [Invention] 30, 30' organic electroluminescent display 300, 300' substrate 320, 320' anode layer 322, 322' cathode layer 340, 340' OLED light emitting multilayer structure 350, 350' insulating layer 360, 360' Insulating region 370' reflecting metal layer 15

Claims (1)

1270319 X. Patent application scope: I An organic electroluminescent display comprising a bottom-up: a substrate; an insulating region distributed in an array, and each insulating region has a predetermined angle with the substrate; a cathode layer above the insulating region and having a well-side side; and an OLED light-emitting multilayer structure and an anode layer on the cathode layer. 2. The organic electroluminescent display of claim 1, wherein the substrate is a glass substrate. 3. The organic electroluminescent display of claim 1, wherein the insulating region is an inorganic film material such as SiOx, SiNx or SiOxNy. 4. The organic electroluminescent display of claim 1, wherein the cathode layer is made of a material having high conductivity and high reflectance. 5. The organic electroluminescent display of claim 4, wherein the cathode layer is made of gold, silver, sho, copper and chrome or a multi-layer composite high-conductivity material. ♦ 6· The organic electroluminescent display of the first item of the patent scope, wherein the insulating layer is a high light transmissive material such as SiOx, SiNx, Si0xNy or the like. . 7. The organic electroluminescent display of claim </ RTI> wherein the insulating layer has a thickness of from 0.5 μm to 5 μm. 8. The organic electroluminescent display of claim i, wherein the anode layer is a transparent electrode film such as ITO, IZO or IWO. 9. The organic electroluminescent display of the scope of claim 1 wherein the substrate can be any flat light/opaque, soft/hard substrate. 16 1270319 - If the first paragraph of the patent application has a 撼 ϋ a, θ ′ touches the excitation light to display H, and the predetermined angle is 90 degrees. 11. For example, the organic Lei Jing Qiaofei electric excitation light display device of the first application patent scope includes a matte polarizing film on the anode layer. 12. A method for fabricating an organic electroluminescent display comprising the steps of: preparing a substrate; fabricating a plurality of insulating regions on the substrate by a lithography process or a micro-inlay process, and each insulating region has a predetermined angle with the substrate Forming a cathode layer on the substrate and the insulating region; forming an insulating layer on the cathode layer by a lithography process or a lithography process; growing an OLED light emitting multilayer structure on the cathode layer and the insulating layer; An anode layer is formed on the OLED light emitting multilayer structure. 13. The method for fabricating an organic electroluminescent display according to claim 12, wherein the step of fabricating a plurality of insulating regions comprises: first coating a material such as poly(p-lyimide), and then using a lithography process to make insulation. Area. The method for fabricating an organic electroluminescent display according to claim 12, wherein the majority of the insulating regions are formed by PVD CVD, and SiOx, SiNx, and oxynitride are grown by PVD CVD. An inorganic film such as SiOxNy; and an insulating region is formed by a lithography process. I5. The method for fabricating an organic electroluminescent display according to claim 12, wherein the step of fabricating the cathode layer comprises first using a metal film such as a splash, a grade, an electron beam or an electric ore; and utilizing micro The shadow etching process produces a metal cathode layer pattern. I6. The method for fabricating an organic electroluminescent display according to the above-mentioned claim, wherein the step of forming the insulating layer comprises first coating a material such as polyimide and using a lithography process to form an insulating layer.験17. The method for fabricating an organic electroluminescence device according to claim 12, wherein the step of fabricating the insulating layer comprises growing by a method such as PVD or CVD, such as oxidized stone cerium (si〇x), nitriding stone χ χ ), a high light transmissive material such as yttrium oxide (SiOxNy), having a thickness of about 〜5 to 5 μm; and an insulating layer formed by a photolithography etching process. 18. The method of fabricating an organic electroluminescent display according to claim 12, wherein the step of fabricating the OLED light-emitting multilayer structure is grown by evaporation to form an LED light-emitting multilayer structure. B 19. The method for fabricating an organic electroluminescent display according to claim 12, wherein the step of fabricating the anode layer is to form a transparent electrode film such as Ting, IZ or lw by sputtering, evaporation and electron beam. . 20. The method of fabricating an organic electroluminescent display according to claim 12, wherein the insulating region is formed into a right angle structure to form a vertical well-like metal cathode layer. 21. The method of fabricating an organic electroluminescent display according to claim 12, further comprising adding a matte polarizing film to the anode layer. 18 1270319 22 - an organic electroluminescent display comprising a bottom-up: a substrate, an insulating region on the substrate and distributed in an array; a reflective metal layer on the insulating region; An anode layer on the reflective metal layer and separated by the insulating region; an insulating layer on the anode layer; an LED light emitting multilayer structure on the anode layer and the insulating layer; and the OLED A transparent cathode on the light emitting multilayer structure. 23. An organic electroluminescence device as claimed in claim 22, wherein the reflective metal layer is a high reflectivity metal material comprising silver. 24. The organic electroluminescent display of claim 22, wherein the transparent cathode layer is a highly penetrating metallic material comprising a metal such as silver or aluminum. 25. The organic electroluminescent display of claim 22, further comprising a matte polarizing film on the transparent cathode. 26· - a method for fabricating a filament display, comprising the steps of: preparing a substrate; forming a reflective region on the substrate by micro-weaving or gamma-ray; forming a reflective metal layer in the insulating region Forming a transparent anode layer on the reflective metal layer; lithographing the money to the lion to form a _ layer on the top of the duck, 19 1270319 growing - OLED light emitting multilayer structure on the transparent anode and the Above the insulating layer; and forming a transparent cathode layer over the OLED LED multilayer structure. 27. The method for fabricating an organic electroluminescence display according to the patent application scope ,%, wherein the reflection gold riding step is a hybrid film, a hybrid inspection, an electron beam or a test (four) process, and a reflective metal is produced by using a lithography process. Layer pattern. / 2 &amp; A method of fabricating an organic electroluminescent display according to the scope of claim 1 wherein the reflective gold is a high reflectivity metallic material comprising silver. 29. If the method of fabricating the organic electroluminescent display of the patent application category No. 5%, the transparent yin yue, the inspection, and the fine growth of the permeable transparent metal film, the transparent cathode pattern is produced. 3〇·申Μ Patent Consumption Section 26 of the method for fabricating an organic electroluminescent display, wherein the transparent cathode material f can be made of inscription, silver or other highly penetrating metal. ^ M. Rushen. The monthly production of the organic electroluminescent display of the 26th patent consumption includes: A gossip formed a matte polarizing film on the cathode. 20