TW474038B - Pixel structure and process for full color organic light-emitting diode display device - Google Patents

Abstract

A pixel structure for full color organic light-emitting diode display device comprises two thin film transistors, a storage capacitor and an organic light-emitting diode connected to a substrate. The pixel structure of the display device has blue organic light-emitting diode or polymer light-emitting diode as the light-emitting material, and low temperature polycrystalline silicon thin film transistor as the current source for the organic light-emitting diode display device and as active driving element. A color conversion medium is used to convert blue light to red or green light to form a full color organic light-emitting diode. The process consists mainly of manufacturing processes for black matrix, island, gate, interlayer, color changing medium, and organic light-emitting diode deposition. By fabricating color conversion medium and low temperature polycrystalline silicon thin film transistor in the same process, a high resolution, high performance, and wide viewing angle display device is produced.

Description

474038 V. Description of the Invention (1) Field of the Invention The present invention relates to the pixel structure and process of organic light-emitting diode (OLED) display elements. In particular, it relates to a daylight structure and process of a full color (OLED) display element. BACKGROUND OF THE INVENTION Flat panel displays are currently one of the most important electronic application products, such as display screens for televisions, instruments, and display screens for notebook computers. Organic electroluminescent (0EL) display elements have light emitting, high luminance, wide viewing angle, fast response speed, and high stability ( high rel iabi 1 i ty), full color, low driving voltage (iow voltage driving), low power consumption and simple manufacturing process. This product will undoubtedly become the best choice for the next generation of flat-panel displays. There are a variety of fabrications and structures of current full-color organic light-emitting display elements. For example, the following five types (a) to (e): (a) The use of a precision mask in a small molecule system to obtain a pixel array of three light colors of red, green and blue (RGB). (b) The white EL element is mainly transmitted through the color filter (c〇 丨 〇r

Page 4 474038 V. Description of the invention (2) f i 11 e r) is filtered to obtain three light colors. (c) Based on blue or purple OEL elements, the original blue or purple light is converted into other light colors through the light conversion layer. (d) Fabricate dielectric stacks of different thicknesses, and use the principles of photophysical reflection and interference to convert the original wideband spectrum into the three RGB primary colors. (e) Based on the double-light-transmitting OEL element, the three light-color elements of RGB are stacked on the same element. A method of fabricating a daylight structure of a thin film transistor (TFT) organic electro-excitation light-emitting element is disclosed in the document of U.S. Patent No. 5,550,066. FIG. 1 is a schematic plan view of a thin film transistor organic electro-optic light emitting device. As shown in FIG. 1, the thin film transistor electro-optic light emitting element 100 mainly includes two thin film transistors 01 and 102, a storage capacitor 103, and a light emitting device disposed on a substrate. Light emitting organic EL pad 104. The thin film transistor ι01 uses a source bus 105 as a data line, a gate bus 106 as a gate line, and a ground bus (grounci) bus) 107 is under the gate bus and capacitor storage. The source electrode of the thin film transistor is electrically connected to a source bus, and its gate electrode includes a part of a gate bus. The light-emitting organic electrical excitation light pad 103 is electrically connected to the drain of the thin film transistor 102. The drain of the thin film transistor 101 is electrically connected to a gate electrode (g a t e e 1 e c t r 〇 d e) of the thin film transistor 102. This gate

Page 5 474038 5. Description of the invention (3) The electrode is electrically connected to the capacitor storage 104. The thin film transistor organic electroluminescent light emitting element is basically composed of pixel uni t units forming a flat display. FIG. 2 is a schematic cross-sectional structure diagram of a thin film transistor and an electromechanical excitation light element 200 made by the method disclosed in this patent document. As shown in FIG. 2, after polysilicon island 208 is implanted on an insulating substrate 201, it is covered with a first gate insulating layer 20 2 and a gate insulating layer 202 Above

A poly-si gate layer 204 is implanted, so that after the source and / or the electrode region is ion-implanted (iopon impiantati),

Formed within this gate insulation layer 202. Ion implantation is conducted with n-type dopant. The gate bus bar 206 is formed on the insulating layer 202, and the surface of the light-emitting element is covered with a second insulating layer 212. Two contact holes are dug out on the insulating layer 212, and the electrode material is used to form electrical properties with the thin film transistor Continuity. The electrode material attached to the thin film transistor 102 simultaneously forms a top electrode 222 of the capacitor storage device 03. Source and ground buses are also formed on the second insulating layer 2 1 2. The top electrode 2 2 2 is in contact with the drain electrode of the thin film transistor 102 as an organic electrode layer 226 as an anode electrode layer 226. Next, a passivating layer 224 of an insulating material is implanted on the surface of the organic electroluminescent element. A taperecj edge is left in the isolation layer to enhance the adhesion with the organic electro-excitation light layer 232 used. The electro-mechanical excitation light layer 232 is implanted on the isolation layer 2 24 and the anode layer 22 6

Page 6 474038 V. Description of the invention (4) = "Finally the last" organic electro-excitation light element is re-implanted with a layer of cathode electrode (cathode electrode layer) 2 34 to form this organic electro-excitation light element 200 . Qiaofeng Power / Don't Under the circumstances of the development of ^, the full-color organic electroluminescence light-emitting display element ί = display market, there are still some problems that must be overcome. Example Element = ΐ Display with South Resolution, High Luminous Efficiency, and Wide Viewing Angle Suspect: Foot: 0EL element, which is a material ', still has brightness and luminous efficiency. The 0EL element with the South molecule as the material, although the overall brightness and luminous efficiency of R (Jb ternary γ) is still not as good as the color with the small molecule. The material used for the EL element cannot be compared with the traditional yellow light process. Niu == Sending out an effective and simple full-color organic “remarkable integration process and structure. Summary of the invention: Inventing grams” Know the shortcomings of organic light-emitting diode display elements. 2 # 的 二 ί ί i #疋, provide a full-color organic light-emitting diode display Xinshe hibiscus: ΐ,; ί: the medium for this full-color organic light-emitting diode display element (WQr W area ⑴Ί 仙 ⑴,-color to crystal, One capacitor stores 4 ports: two 0 regions, two thin film electric diode element structures. One organic light emitting diode connected to a substrate

Page 7 474038 V. Description of the invention (5) ----- Another object of the present invention is to provide a process for manufacturing the pixel structure of the full-color organic light emitting diode display element. The process of this pixel structure mainly includes the following steps: (a) black matrix process; (b) island hill process; (c) gate process; (㈧interlayer process; (e) color conversion media process; and ( f into the organic light emitting diode (QLED deposition) process. 'According to the present invention, the pixel structure of the organic light emitting diode display element is a blue organic light emitting diode or a polymer light emitting diode. It is a light-emitting material. A low-temperature polycrystalline silicon (10w temperature Si, ", LTPS) thin-film transistor is used to provide current to this organic light-emitting diode display element, and as an active driving element. The color medium uses blue light. Converted to red or green light to form a full-color light-emitting diode. Since the color conversion medium * LTps thin film transistor is combined in the same process, it can be made into a high-resolution, high-performance, alpha and wide viewing angle display. Yuan: Hereby, the above and other objects and advantages of the present invention will be described in detail with the following drawings, detailed descriptions of the embodiments, and the scope of patent applications. Brief description of the drawings Body having electroluminescent element - Graphic overview schematic sectional structural view of FIG. 2 is a one.

474038 5. Description of the invention (6) FIG. 3 is a schematic circuit diagram of a full-color organic light-emitting diode display element according to the present invention. FIG. 4 is a schematic plan view of a full-color organic light emitting diode display element according to the present invention. FIG. 5 is a schematic cross-sectional structure view along line B-B ', illustrating the steps of the black matrix process of the full-color organic light-emitting diode display element of the present invention.

FIG. 6 is a schematic cross-sectional structure view along line B-B ', illustrating the steps of the island hill manufacturing process of the full-color organic light-emitting diode display element of the present invention. Fig. 7 is a schematic cross-sectional structure view along line B-B ', illustrating the steps of the gate manufacturing process of the full-color organic light-emitting diode display element of the present invention. Fig. 8 is a schematic cross-sectional structure view along the line B-B ', illustrating the steps of the intermediate layer manufacturing process of the full-color organic light-emitting diode display element of the present invention.

Figs. 9a to 9c are schematic cross-sectional structural diagrams along line B-B ', illustrating the steps of a color changing medium process of the full-color organic light emitting diode display element of the present invention. FIG. 10 is a schematic cross-sectional structure view along the line B-B ', illustrating the whole of the present invention.

Page 9 474038 5. Description of the invention (7) The steps of implanting the organic light-emitting diode system of the color organic light-emitting diode display element. FIG. 11 is a schematic cross-sectional structure view taken along line A-A 'in FIG. 4. Description of drawing number 1 0 0 Conventional thin film transistor 1 0 1, 1 0 2 Thin film transistor 104 light emitting organic electric excitation 1 0 5 source bus 1 0 7 ground bus 2 0 1 insulating substrate 204 polycrystalline silicon gate layer 2 0 8 Polycrystalline silicon island mound 2 2 2 Top electrode 2 2 6 Anode electrode layer 234 Cathode electrode layer Organic electro-optic light element 1 0 3 Capacitor memory pad 1 0 6 Gate bus bar 2 0 2 First gate insulating layer 2 0 6 Gate Bus bar 2 1 2 Second insulation layer 2 2 4 Isolation layer 232 Organic electro-excitation light layer

3 0 0 The daylight structure of the full-color organic light-emitting diode display element of the present invention Ί \, T2 thin film transistor Cs capacitor storage device 3 0 1 gate line 3 0 2 data line 3 0 3 organic light-emitting diode

Page 10 474038 V. Description of the invention (8)

4 0 3 Black matrix area 4 0 6 Gate busbar 5 0 1 Edge substrate 5 0 4 Buffer layer 4 0 5 Data busbar 40 7 Vdd busbar 5 0 2 Black matrix area 6 0 2 Polycrystalline silicon layer 606 P + Dopant 7 0 2, 7 0 4 Gate electrode 8 0 2 Intermediate layer 604 N + type dopant 6 0 8 Gate oxide layer 7 0 6 Gate metal

902 Isolation layer 904 Color conversion medium region 9 0 6 Steel tin oxide 1 0 0 2 Material of organic light emitting diode 1 004 Cathode metal layer 1102, 1104 N + type inclusions Detailed description of the invention

Page 11 V. Description of the invention (9) --- The simple electricity of the invention is a fundamentally invented full-color organic light-emitting diode display element. Every way is not intended. The capacitor dual structure 300 of this full-color organic light-emitting diode display element mainly includes two thin-film transistors T1 and I, a target device, and an organic light-emitting diode LED structure. Thin ^ = and W include -source electrode, -no electrode and -interval 电. The gate electrode of the 2-membrane transistor 1 contains a knife of a gate wire 30 1. The source electrode of the thin film transistor is electrically connected to a data line 302, = the drain electrode of the thin film transistor is electrically connected to the gate electrode of the thin film transistor 1 '/ the gate electrode of the special film transistor A Electrically connected to the capacitor storage cs. The 0LED element structure is electrically connected to the non-electrode of the thin film transistor I. Fig. 4 is a schematic plan view of a full-color organic light-emitting diode display element according to the present invention. Referring to FIG. 4, the thin film transistor L and the qleD element are connected in series, and the capacitor storage Cs is connected in series with the thin film transistor T1. The 0LED element is connected to an insulating substrate (not shown in the figure). The black matrix region 4 0 3 is formed above the insulating substrate. The thin film transistor uses a data bus line (data bus line) 40 5 as a data line, a gate bus line (gate bus line) 40 6 as a gate line, and a Vdd bus line 407 is a power supply (power supply ) Bus. In the present embodiment, a low-temperature polycrystalline silicon thin film transistor is used to provide current to this OLED element, and it is used as an active driving element. The LED device uses a blue organic light emitting diode or a polymer light emitting diode as a light emitting material.

Page 12 V. Description of the invention (10) Figure 5 ~ Figure 10 Rabbit Figure Figure

11 is a cross-sectional structure diagram along line B-B 'shown in FIG. 4 along line B-B'. Q As mentioned earlier, the potential of the pixel structure of ^ is the king-shaped organic light-emitting diode display process and the intermediate layer system, which mainly includes the black matrix process, the island hill process, and the two-pole system process. The process of color conversion media, and the implantation of organic light in the same process as the color conversion media * ltps thin film transistor light in the same process according to the present invention, in order to form a full color conversion media process to convert blue light to red, and wide range: Diode. Household jins can be made into high resolution :: display elements of the corner. Below ^ =, along the line β_β, the full-color servant ρ α Μ 本 of the present invention is illustrated in FIG. 10 as an example. Steps of each process of the organic light emitting diode display element

FIG. 5 is a schematic cross-sectional structure diagram along the first step of the Rado R: $, illustrating the edge substrate 501 of the present invention. In this process, firstly, the -provided area 5 02 is implanted and fixed. The second plate is provided with a top surface and a bottom surface. A black moment black matrix area 5 0 2 is inserted above the top surface of the eup substrate 5 0 1. . Next, in the buffer layer 504, FIG. 6 is a schematic diagram of the _judging & plane structure along the line B-B, illustrating the present invention.

Page 13 474038 5. The second step of the description of the invention (11): the island hill process. In this process, a polycrystalline cutting layer 602 is first implanted above the buffer layer 5H to define the source and non-electrode regions of the thin film transistor T1 and the source and drain regions of the thin film transistor I. Finally, a polycrystalline silicon island is defined and formed using a laser crystallization method and a money engraving method, as shown in FIG. 6

In this embodiment, the source and drain regions of the thin film transistor are formed after the ion implantation, and are turned on with a jealous impurity 604 above the buffer layer 504. On the other hand, the source and drain regions of the thin film transistor I are connected above the buffer layer 504 by a p-type dopant 606. Fig. 7 is a schematic sectional structural view along the line B-B ', illustrating the second step of the present invention: the gate process. In this process, an electrical material is implanted above the polycrystalline silicon island mound to form a gate layer. In this embodiment, first, a gate oxide (608) and a gate metal (706) are implanted on the polycrystalline stone Xiuqiu hill respectively. This gate layer is then defined, including defining thin film transistors and & gate electrodes 702 and 704.

Fig. 8 is a schematic cross-sectional structure view along the line B-B ', illustrating the fourth step of the present invention: the intermediate layer process. In this process, first, an intermediate layer is implanted above the gate layer and above the polycrystalline silicon island hill. By definition, the source and drain are implanted, and the source and drain metal regions are defined.

Page 14 474038 V. Description of the invention (12) Figures 9a to 9c are schematic cross-sectional structural diagrams along line B-B ', illustrating the fifth step of the present invention: the process of color conversion media. According to the present invention, the color conversion medium and the L T P S thin film transistor are combined in this process. In this process, first an isolation layer 902 is deposited over the intermediate layer 802, and then a color conversion medium is defined. The process of defining a color conversion medium includes three steps in succession: (a) Passivation etching to define the color conversion medium area 904 and a part of the contact area with the electrode layer. The results are shown in Figure 9a . (B) Spin coating this color conversion medium region 904 repeatedly, and use the general photolithography technique to define individual red, green, and blue pixels (discrete R, G, and B pixels) color conversion media pattern, after three times of spin coating and exposure and development with general yellow light lithography technology, the results are shown in Figure 9b. (C) Sputter—a layer of transparent conductive material, such as indium tin oxide (ITO) 906, above the display element, and define this layer of transparent conductive material. The result is shown in Figure 9c Show. Fig. 10 is a schematic cross-sectional structure along line B-B ', illustrating the sixth step of the present invention: the process of implanting an organic light emitting diode. In this process, first, a layer of organic light emitting diode material 002 is implanted above the indium tin oxide layer 906 and above the isolation layer 902. Finally, a cathode metal layer ((: & 1: 11 heart metal layer) 1 0 04 is implanted on top of this layer of organic light emitting diode material 1 02. Fig. 10 shows the organic light emitting device of the present invention. Diode display

Page 15 474038 V. Description of the invention (13) Diagram of day element structure of element. According to the present invention, a complete cross-sectional structure of a diode or polymer along line B-B is illustrated. This layer of organic light-emitting diode uses a blue organic light-emitting diode as a light-emitting material. Diode is i ': Ming uses m-color organic light-emitting diode or polymer light-emitting medium: two forms a full-color light-emitting diode. Moreover, since the color conversion resolution and the two-film transistor are combined in the same-process, it can be made into a display device with high > Wen Yue Dagger 'and wide viewing angle. The thin-film electric circuit is as follows: J in Fig. 2: Schematic diagram of the cross section of the line H ', in which the material. The source and drain regions 1102 and 1104 of Cong1! Are N + type dopants. It cannot be said that this is only a preferred embodiment of the present invention. That is to say, it is within the scope of application of the present invention. = Nettle changes and modifications should still be covered by the invention patent

Page 474038 Schematic description

Page 17

Claims (1)

4. The scope of the patent application: The organic light-emitting diode display element has a daylight structure, which is connected to: the top of an insulating substrate with a top surface and a bottom surface. The pixel structure of the display element includes: It is defined on the top surface of the insulating substrate; it is defined above the mE array and above the source and non-electrode regions of the buffer layer-thin film transistor, and the definition of the transistor The source and drain regions are implanted above the buffer layer with a dagger, and are defined and formed using the -Ray :: Yue method and etching method. Multi: "" above the mound, and at the gates of the gate-electric and second thin-film transistors; * above the middle and above the polycrystalline "mounds; and the source and drain isolation layers , Which is implanted on the intermediate layer ^... Color conversion medium area; square, and in the isolation layer == :! The electric material layer is implanted above the isolation layer; The element is implanted on the transparent conductive material layer and the isolation layer; and the material of the material: j metal layer is implanted in the element of the organic light emitting diode material. The full-color organic light-emitting diode described in item 474038 6. The scope of the patent application shows the daylight structure of the element, wherein the element of the organic light-emitting diode is electrically connected to the drain of the second thin-film transistor. 3. The pixel structure of the full-color organic light-emitting diode display element as described in item 1 of the scope of patent application, wherein the drain electrode of the first thin-film transistor _ and the gate electrode of the second thin-film transistor Electrical connection. 4. The daylight structure of the full-color organic light-emitting diode display element according to item 1 of the scope of patent application, wherein the second thin-film transistor system is a low-temperature polymerized silicon thin-film transistor to provide current to the organic Appealing element of light emitting diode. 5. The daylight structure of a full-color organic light-emitting diode display device as described in item 1 of the scope of patent application, wherein the second thin-film transistor system is an actively driven device. 6. The daylight structure of the full-color organic light-emitting diode display device according to item 1 of the scope of patent application, wherein the gate electrode of the second thin-film transistor is electrically connected to the capacitor storage. 7. The daylight structure of the full-color organic light-emitting diode display element according to item 1 of the scope of patent application, wherein the second thin-film transistor is connected in series with the element of the organic light-emitting diode, and the capacitor The reservoir is connected in series with the first thin film transistor. Page 19 474038 6. Application scope g A full-color process has the following steps: (a) Provide an insulation surface, and use a surface (b) to buffer a thin-film electrical thin-film transistor (c) using a lightning ⑷ in the layer (e) in between and 换 in the change (g) in the fixed (h) in the planting (i) in the polysilicon of the polysilicon 5 the gate layer, and> the gold and the intermediate medium region the isolation meaning The transparent and transparent layer has a polar metal machine light-emitting step: the source substrate is a black matrix of the edge substrate and the source crystal body of the upper crystal body on the black layer; the upper area of the Shixi Island hill is defined by the upper domain of the regional layer; The top surface of the layer is made of a conductive material, an organic light-emitting layer, and a pixel structure of a diode display element. This insulating substrate is implanted with a top surface layer and a bottom surface area and is defined above the top matrix area of the insulation substrate. A buffer layer; a square polysilicon layer is implanted to define a first source and drain region, and a first and non-polar region; and an etching method to define and form an upper implanted electrical Polycrystalline silicon One is implanted above the island hill, the source and the drain are implanted, and the middle; the Weiyi source is implanted-an isolation layer, and defines the color transfer ^ implant-a layer of transparent conductive material, and the layer above And the material of the photodiode of the isolation layer; and above, the material of the diode is planted above 474038 6. Application for Patent Scope 9 · The process of manufacturing a pixel structure of a full-color organic light-emitting diode display element as described in item 8 of the scope of patent application, wherein, in step (b), the first thin film transistor The source and drain regions of the second thin film transistor are above the buffer layer and are turned on by N + type impurities, while the source and drain regions of the second thin film transistor are above the buffer layer and are made of P + type impurities To turn on the conductive structure of the full-color organic light-emitting diode display element according to item 8 of the patent application, wherein the electrical material in step (d) includes a gate oxide and a gate metal. . 11. The manufacturing process of the daylight structure of the full-color organic light-emitting diode display element according to item 8 of the scope of patent application, wherein step (d) further includes defining the first and second films in the gate layer. Steps of the gate of a transistor. 1 2 · The manufacturing process of the daylight structure of the full-color organic light-emitting diode display element as described in item 8 of the scope of patent application, wherein the process of determining the color conversion medium in step (f) further includes the following steps: ( f 1) etch the isolation layer to define a part of the color conversion medium region and the contact area of the electrode layer; ~ (f 2) repeatedly spin-coat the color conversion medium region, and use — # 黄光 微 影 技术 to define individual Full red, green, and blue color conversion media patterns; and ..., 474038 6. Scope of patent application (f 3) A layer of transparent conductive material is sputtered on the display element, and the transparent conductive layer is defined. 13. The light-emitting element structure of the full-color organic light-emitting diode display element according to item 8 of the scope of patent application, wherein the transparent conductive material layer in step (g) is indium tin oxide. 14. 15. The manufacturing process of the full-color organic light-emitting diode as described in item 8 of the scope of patent application === pieces of daylight structure, wherein the organic meal light-polarity in step (h) is blue Organic light-emitting diodes are luminescent materials. The manufacturing process of the denier structure of the full-color organic light-emitting diode display element described in item 8 of the patent claim range, wherein the organic X-pole of step (h) is a polymer light-emitting diode The body is a luminescent material.