TW514751B - Dual-panel active-matrix organic electroluminescent display - Google Patents

Abstract

There is provided a dual-panel active-matrix organic electroluminescent display, which includes an organic electroluminescent display panel, an active device panel and conductive material between the two panels. These two panels form a composite structure and the conductive material between the two substrates is used as a combining layer. The method for manufacturing this dual-panel active-matrix organic electroluminescent display comprises the manufacture of the organic electroluminescent display panel, the manufacture of the active device panel, and bonding of the conductive material for combining the two panels. The two panels can be made separately, thereby increasing the circuit layout area of polysilicon TFT. Alternatively, amorphous TFT is used with n-channel source follower to implement the circuit and solve the problem in uneven illumination effect, thereby increasing the resolution of the electroluminescent display. When bonding is performed by thermal pressing, no transparent area is reserved in the pixels of the lower plate. When illuminating by ultraviolet, only a small amount of transparent area is reserved for curing by ultraviolet. Accordingly, the illuminating area of the electroluminescent display is nearly 100%.

Description

514751

The invention relates to an organic electroluminescent display. In particular, it relates to a full color active matrix organic light emitting display using a dual panel structure. 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 notebook-type electric crescent products. The organic light-emitting display element has self-emission (1 丨 ght emitting), high luminance (high luminance), wide viewing angle (wide viewing angle), high response speed (fast response speed), high stability (high rel iabi 1 i ty) , Full color, low driving voltage (iow voltage driving), low power consumption (low power consumption) and simple process (simple process). This kind of product will undoubtedly become the mainstream of the current flat panel display. Traditional passive organic light-emitting display elements, although cheap to produce and simple to process, have poor resolution and can only be used for small-sized, low-resolution displays. Organic light-emitting display elements, such as thin film transistors (thi n f i 1 transistor TFT), have high resolution, high brightness, and low power consumption. Generally speaking, active driving is high-resolution drawing

Page 5 514751 V. Description of the invention (2) Mainstream of mass drive technology. As the size of the display becomes larger and larger, and the requirements for resolution become higher and higher, and full color is required, the active driving of organic light-emitting display elements with full color is bound to become a major trend. In US Pat. No. 5,550,066, a pixel structure and a process for fabricating an organic emitting light (OEL) element of a thin film transistor are disclosed. FIG. 1 a and FIG. 1 b are respectively a schematic view of a plane (p 1 a n v i e w) and a cross-sectional view (c r s s s e c t i ο n a 1) of the thin film transistor organic electro-optic light-emitting device. ._ As shown in Fig. 1a, the pixel element structure of the thin film transistor electro-optic light emitting element 100 includes two thin film transistors 101 and 102, a storage capacitor 103, And a light emitting organic EL pad 104 placed on the substrate. The thin film transistor 1 〇1 uses a source bus (s our ce bus) 105 as a data line, a gate bus 106 as a gate line, and a ground bus bus) 107 is under the gate bus and capacitor storage. A source electrode of the thin film transistor 101 is electrically connected to a source bus, and a gate electrode thereof includes a part of a gate bus. The light-emitting organic electrical excitation light pad 104 and the drain of the thin film transistor 102 are electrically connected. The drain of the thin film transistor 101 is electrically connected to the gate electrode of the thin film transistor 102. The thin film transistor organic electroluminescent light emitting element is basically a pixel unit forming a flat display.

5. Description of the invention (3) (pixel uni t). The schematic cross-sectional structure of FIG. 1b illustrates the manufacturing process of the pixel element structure of the thin-film transistor organic light-emitting element. As shown in FIG. Lb, polycrystalline silicon island hills (? 〇15 ^; [14〇1141) (3) 118 are implanted above the insulating substrate 111, and then covered with a first gate insuiating layer. ) 112, a polysilicon gate (poly 4 to 4) layer 114 is implanted above the gate insulation layer 112, so that the source and drain regions are after ion implantation Is formed in the gate insulating layer 112. The ion implantation is conducted by N-type dopant. The gate bus 116 is formed on the insulating layer 112, and a second insulating layer is covered on the surface of the light-emitting element. 1 丨 3, two contact holes are dug out of the insulating layer 11 3, and the electrode material is used to form electrical conduction with the thin film transistor. The electrode material attached to the thin film transistor 1 〇2 also forms the top electrode of the capacitor storage 103 (Top electrode) 122. A source bus bar and a ground bus bar are also formed on the second insulating layer 113. The top electrode 122 is in contact with the source of the thin film transistor 102, and corresponds to the drain of the thin film transistor 102. Contact is the anode electrode layer (an〇de electr〇de la yer) 136. Next, a paSSiVating layer 124 is implanted on the surface of the organic electro-excitation light element. This isolating layer calls for tapered edges to come. Enhance the adhesion to the organic electroluminescent layer 132. The organic electroluminescent layer 132 is implanted above the isolation layer 124 and the anode layer 136. Finally, the surface of the organic electroluminescent layer is re-implanted. A cathode electrode layer (cathode 514751 V. Description of the invention (4) electrode layer) 134 〇 The structure of the traditional active driving organic light-emitting display element must use one of the following methods to drive the organic light-emitting diode transistor Production:

(1) Source follow p-channel (TFT) source, and in conjunction with a normal type organic electric luminance (OLED) process, the light emitting layer and the TFT-array ( TFT-array) is fabricated on the same substrate, and the light source is transmitted through the TFT substrate. 'Cannot emit light in the active device layout area. The TFT-array emission area (aperture rati0) is usually only 10 ~ 30%. In the future, There will be bottlenecks in improving the resolution. (2) A structure in which the source electrode follows a thin film transistor of n-channel (source fnow n-chan n el) and cooperates with an inverted type OEL. However, the process of the reverse type 0EL is immature compared with the process of the normal type 0EL. The luminous efficiency of the L-type OEL process is 1 to 2 stages higher than that of the reverse-type Oel process. Therefore, the feasibility of the structural method of (2) is not high.

In addition, if a poly-Si TFT process is used,

, The relationship of σ-boundary voltage variation ’Using this method to implement the active formula θ E is difficult to show the gray level (g r a y 1 e ν e 1). Development situation under Shen Fen, full-color active driving organic light-emitting display

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In order to capture the market of flat-panel displays, another high-performance full-color active type has to be summarized. SUMMARY OF THE INVENTION The above-mentioned problems must be overcome to develop machine-emitting displays. Objective: To overcome the shortcomings of traditional organic light-emitting diode displays. Its main device is a dual-substrate active organic light emitting device. This organic light-emitting display mainly includes the upper M1 f ^^ as ^ ^ ^, ^, when the upper layer of the organic light-emitting display substrate 3, the lower layer I k & Germany: the plate L and the conductive material interposed between the two substrates, and this A two-soil, composite structure with two conductive substrates made of conductive material in the preferred embodiment of the present invention. The upper organic light-emitting display substrate mainly includes a transparent substrate and a layer of indium tin oxide plated on the substrate. (indium tin oxide, ITO), a layer of OEL film (mine) over the indium tin oxide layer, a cathode layer ('cathode layer') plated on top of the oel film, and a covered insulating layer (passvati). rl iayer). A window (wi n (jow)) is left above the cathode layer as a contact area with the lower active element substrate. In this embodiment, the 'lower active element substrate is a TFT panel (pane 1), which is a TFT panel. The single day element on the device includes a scan bus line, a data bus line, and an active drive circuit layout. The pixel contains a conductive layer that is bonded to the upper substrate to conduct electricity.

^ / 51 V. Description of the invention (6) Contact area According to this, the conductive material layer between the two substrates bundles the two substrates. The voice of this conductive material is a non- 堃 a sub-position survey stack. It is conductive, but it does not conduct in the lateral direction. Power on and off Another object of the present invention is to provide a method for light display. This manufacturing method mainly includes: J: flying organic matter bonding method. According to the invention of the two conductive materials combined with the two plates, the Λ dual-substrate active organic light-emitting display clay plate can be made separately. Two pieces of active component panel books or only a small part of the transparent area need to be reserved for f * ## πιν &######## "Outer thermosetting (in conjunction with the following drawings and detailed description of the examples), the above and other objects and advantages of the present invention will be described in detail below. Called a detailed description of the dry invention Figure 2 is a dual substrate according to the present invention Active-planar schematic diagram. This dual-substrate active type has organic components, λ w ^ I Α luminescent, and the display device is based on the fifth and seventh invention description (7) t as the combination and layer. One layer of the substrate is a full-color or monochrome organic light-emitting display soil plate (called the upper plate) 211. Its structure can be made of a normal type or a reverse type structure. The OEL material can be a polymer and small molecule series, and the substrate can be It is a glass substrate or a plastic substrate. The other layer of the substrate is the active device panel (the bottom plate is the lower plate) 221, and its structure can be a polycrystalline silicon or an amorphous silicon substrate. The conductive material 231 joining the two plates may be an anisotropic conductive film (ACF), anisotropic conductive adhesive (ACA), conductive resin, silver glue (Ag ep〇). xy), or metal bumps. The bonding method is ultraviolet irradiation or thermal curing. The resistance of the conductive material is between 1.06 ohms per square. The following describes the manufacturing process and cross-sectional structure of this double plate. 3a to 3d sequentially illustrate the process of manufacturing the upper board of the present invention. First, a transparent material layer 3 1 5 is plated on the top surface of the transparent substrate 3 丨 with top and bottom surfaces, as shown in Figure 3a. Then, a patterned OEL film 321 is plated. As shown in FIG. 3b, the manufacturing process of the small-molecule organic light-emitting diode (0LED) can be processed by a shadow mask, and the polymer 0LED can be used. Inkjet print processing. The OEL film may be a hole transport layer, an organic light emitting layer (ORL), an electron transport layer, and the like. Next, a cathode layer 331 is plated. As shown in FIG. 3c, the cathode layer may be a metal such as Ming.

Page 11 514751 V. Description of the invention (8) Finally, as shown in Fig. 3d, an insulation layer (passvation layer) 341 is covered, as an insulator between pi xe 1 and water and oxygen are prevented from damaging the 0EL Film 321. In addition, it is worth mentioning that there must be a window above the cathode layer as an area in contact with the lower active device panel. FIG. 4 is a schematic cross-sectional structure diagram of the upper organic light-emitting display substrate manufactured according to FIG. 3. & Fig. 5 is a schematic diagram of a single element on a substrate of an underlying active device according to the present invention. As shown in FIG. 5, a single day element includes a scan bus line 501 (may be one or more metal lines), a data bus line 502 (may be one or more) Metal lines), and the active driving circuit layout section 503. It is necessary to include a contact area 504 with the upper plate as a conductive bond. η In the embodiment of the present invention, the underlying active element substrate system—the TFT panel may be a polycrystalline or amorphous TFT. Its structural design is familiar to those skilled in the art, and a schematic cross-sectional structure is shown in FIG. 6a. Show. Referring to this figure, ^ is briefly explained as follows: (a) a buffer layer (bu ^ ^ r layer) 621 is above the glass substrate 611; (b) a polymer i (p0ly ^) is implanted above the buffer layer 621; si) or amorphous silicon layer 631, which is used to define the source region 631 & and the non-polar region 631b of the TFT, (c) using a crystallization and etching method to define and form / a polymerized crystalline silicon island hill 6 4 1, ( d) planting an electrically conductive material over the polymerized crystalline silicon island mound 6 41 to form a gate layer 651, (e) above the gate layer 651 and ^

Page 12 514751 V. Description of the invention (9) '-Above the polycrystalline crystalline stone Xijiu Qiu 6 4 1, an intermediate layer (interlayerHei, (f)) is implanted, and then the contact hole is dug out, and the middle sound A layer of metal layer 671 is overlaid on top of 661. (g) A layer of metal 6-1 is overlaid on top: a layer of isolation layer 681 (can be a photoresist material or a non-photoresist material). (H) After that, a yellow light process is used. (Photolith〇graphy pr〇cess), using a mask pattern, after exposure and development, after etching the partition, coating-layer photoresistive type color phosphor film, on the intermediate layer 661 = on top = defining a color filter Sheet 6 91, (i) Finally, a layer of transparent material, such as indium tin oxide, is implanted as an anode electrode layer on top of the isolation layer 6 8 J, the color filter 691, and the entire surface. It is electrically connected to the drain electrode of another thin-film transistor. Figure 6b is a schematic diagram of Figure 6a. After the upper and lower boards are manufactured, one of the boards must be coated with a conductive and adhesive material 711. , The pixel to pixel (pixel to pixel) to glue the two plates in position, as shown in the figure As shown in Figure 7a. Because the conductive and bonded material is an anisotropic conductor (similar to the rainbow gate, only the upper and lower electrode parts will conduct electricity, and it will not conduct in the horizontal direction. Figure 7b shows the red and green after the two plates are bonded. The three schematic diagrams of the three colors of blue and blue. The method of joining the two plates can be treated by thermosetting or ultraviolet irradiation, and the conductive and adhesive materials are also different. Figure 8a shows hot air 811. Add on the surface of the transparent substrate 3 11 of the upper plate and the surface of the glass substrate 611 of the lower plate, and use low-melting point metal bumps.

Page 13 514751 V. Description of the invention (10) 812 As a conductive and adhesive material. Figure gb shows a heater M2 pressure 821 on the surface of the transparent substrate mi of the upper plate, and the surface of the glass substrate 611 of the lower plate is illuminated with UV light 823, and = UV The photo-curable anisotropic conductive adhesive 825 serves as a conductive and adhesive material. FIG. 8c shows a heater 822 with heat and pressure 831 on the surface of the transparent substrate 311 of the upper plate, and an anisotropic conductive film 827 is used as a conductive and adhesive material. The resistance values of these conductive and adhesive materials used in Figure 8 are between 0.1 · 106 ohms per square. When using the hot pressing method, the daylight element of the lower board does not need to reserve a transparent light guide area. When using ultraviolet light, only a small part of the transparent area needs to be reserved for thermosetting. Accordingly, the light-emitting area of the light-emitting display of the present invention is close to 100%. Furthermore, since the light emitting layer and the TFT-array are fabricated on different substrates in the present invention, the light source can be transmitted through the TFT substrate, so γ increases the layout area of the polycrystalline silicon TFT circuit and solves the problem of light emitting effects. Ask evenly. The problem of non-uniform luminous effect can also be solved by using a circuit of amorphous stone T f τ with an n-channel source follower type (n channel source f0u00w type). Therefore, the resolution of the light emitting display is improved. Because the boards are made separately, their yield and yield are also improved. The two-chip base In summary, the present invention overcomes the disadvantages of the traditional organic light-emitting diode display by using a full-color active two-display device with a dual substrate structure. The clothing process is simple, and has high resolution, high luminous efficiency and high output.

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Page 15

514751 Brief description of the drawings Brief description of the drawings Figure 1a is a schematic plan view of a conventional thin-film transistor organic electro-optic light-emitting device. FIG. 1 b is a schematic cross-sectional structure diagram of FIG. 1 a.

FIG. 2 is a schematic plan view of a dual substrate active organic light emitting display according to the present invention. 3a to 3d sequentially illustrate the process of manufacturing the upper substrate of the present invention. FIG. 4 is a schematic cross-sectional structure diagram of the upper organic light emitting display substrate manufactured according to FIG. 3. Fig. 5 is a schematic diagram of a single day element on a substrate of an underlying active device according to the present invention.

FIG. 6 a is a schematic cross-sectional structure diagram of FIG. 5. Fig. 6b is a simplified diagram of Fig. 6a. FIG. 7a is a schematic view of the double substrates of FIGS. 4 and 6b after being bonded.

Page 16 514751 Brief description of the diagram. Figure 7b is the overall schematic diagram of the three light colors of the three substrates red, green, and blue. Figure 8a illustrates a method of joining the two plates of the present invention, in which hot air is separately added to the surface of the upper substrate. And the lower substrate surface, and a low melting point metal bump is used as a conductive and adhesive material. Fig. 8b illustrates another embodiment of the two-plate bonding method of the present invention, in which a heater is pressed on the surface of the upper substrate and the surface of the lower substrate is irradiated with ultraviolet light, and ACA is used as a conductive and adhesive material. FIG. 8c illustrates another way of bonding the two plates of the present invention, in which the heater on the surface of the upper plate is hot pressed, and ACF is used to conduct and adhere to the drawing. FIG. Element 101, 102 Thin film transistor 103 Capacitor storage 1 0 4 Light emitting organic electrical excitation light pad 1 0 5 Source bus 1 0 6 Gate bus 1 0 7 Ground bus 111 Insulating substrate 11 4 Polymeric silicon gate layer 11 2 First gate insulation layer 11 6 gate bus

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11 8 Polycrystalline silicon island mound 1 2 2 Top electrode 11 3 Second insulating layer 1 2 4 Isolation layer 132 Organic electroluminescent layer 134 Cathode electrode layer 1 3 6 Anode electrode layer 211 Organic light-emitting display substrate 221 231 Conductive material Active element panel

3 11 Transparent substrate 321 OEL film 3 4 1 Insulating layer 315 Transparent material layer 3 3 1 Cathode layer 501 503 504 Scan bus line 502 窨% l >. ^ Ζ Shell bus active drive circuit layout part contact area 6 11 The glass separation substrate 6 3 1 polymerizes; 5 or amorphous stone layer 6 3 1 b > and pole region 651 gate layer 6 71 metal layer 6 9 1 color filter 711 conductive and adhesive material 6 2 1 buffer layer 6 3 1 a Source region 641 Aggregate A κ 0 Crystalline silicon island hill 6 6 1 Intermediate layer 681 Isolation layer 6101 Transparent material layer

Page 18 514751 Brief description of the diagram 811 Hot air 8 2 1 Pressure 823 UV light 827 Anisotropic conductive film 8 1 2 Low melting point metal bump 822 Heater 8 2 5 Anisotropic conductive adhesive 831 Hot pressing

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Claims (1)

514751 6. Scope of patent application1. One kind of dual; one organic, one active; one conductive; Bulletin 丨 Board active-Shoulder light emitting display is not fast 'includes: all light display substrate; element substrate; and the combination of time and quality Layer between the two substrates, and a two-substrate active organic light-emitting display as described in item 1 of the patent application scope, wherein the organic light-emitting display substrate further includes: x # a transparent substrate provided with Top and bottom surfaces; a transparent material layer, plated on the top surface of the transparent substrate; layer I, a patterned organic electroluminescent film, plated on the transparent material layer, the patterned organic electroluminescent film; and = Layer 'covered on top of the cathode layer as the light-emitting display film; an insulator between deniers and to prevent damage to the organic electro-excitation light of the layer ^ window above the cathode layer is left as a substrate contact region. /, Q active element 3. As shown in item 丨 of the patent application scope, wherein the active element m substrate / active organic light emitting display substrate is a thin film transistor panel. 4. Such as. The double-base state described in item 3 of the scope of patent application, wherein the single-pixel on the thin-earth organic light-emitting display panel includes six. The scope of the patent application [two f-scan busbar, Congestion of at least one piece of data * The government, road layout part, and the pixel contains a light-emitting display board of the female coffee machine as a conductive contact area. The display device of the block and the female application for the month of the patent], in which the indulgent 14-type organic light-emitting display is connected by purple ray line or thermosetting. 6. The indicator as described in item 丨 of the scope of the patent application, the towel, the conductive material of the two plates joining the light emitting display T, anisotropic conductive adhesive, conductive resin, silver shell; = conductive block. 4 疋 Metal convexity The dual-substrate master as described in item 1 of the scope of the patent application, wherein the conductive material x machine which joins the two plates has a light-emitting display square of 0.1 to 106 ohms. The resistance value of the shell is between every 8. The main body of the dual substrate as described in item 丨 of the patent application scope, where t, the organic electroluminescent film is electric: screen, light-emitting: light-emitting layer or electron wheel layer . The two-substrate active organic light-emitting display device described in this section has a structure of a polycrystalline silicon or an amorphous silicon 4-film transistor panel. 9. 514751 Six 'application for patent scope 10 · — A process for manufacturing an organic light emitting display substrate of a dual-substrate active light-emitting display. The light-emitting display uses the organic light-emitting display substrate, called an upper plate, and two active substrates, called a lower plate. , The composite structure is formed, and a conductive material bonding layer is lost between the two substrates, and the two substrates are bonded in a -joint manner. The organic light emitting process includes the following steps: (a) providing a top and bottom Transparent substrate on the surface; (b) Plate a layer of transparent material on the top surface of the transparent substrate. (c) plating a patterned electrically excited light film on the transparent material layer; (d) plating a cathode layer on the organic electrically excited light film; and (e) covering the cathode layer An insulating layer is used as an insulator between the light emitting display and the organic electro-excitation light film to prevent damage to the layer; wherein a window is left above the cathode layer as an area in contact with the substrate of the active element. 11. The manufacturing process of the organic light emitting display substrate according to item 10 of the scope of the patent application, wherein the organic electroluminescent film is made by a shadow mask method of a small molecule organic light emitting body. 12. The process of organic light-emitting display substrates and panels as described in item 10 of the scope of patent application, wherein the organic electro-luminescent film is made by a high-molecular organic light-emitting ink nozzle printing method. Page 22: M4751 6. The scope of application for patents 13.1 The process of organic light-emitting display substrates described in item 1 of the scope of application for patents, wherein after step (e), it further includes coating the conductive layer on the insulating layer of the organic light-emitting display substrate with the conductive material. The step of the material bonding layer 'adhesively bonds the two machine boards with the day-to-day-to-day. 14. The process of organic light-emitting display substrates described in item No. 丨 0 of the scope of application for patents, wherein the active device substrate is coated with the conductive material bonding layer, and the dual-machine boards are aligned and bonded together with pixels. Canton 15. The manufacturing process of organic light-emitting display substrates as described in item 10 of Shen Qing's patent scope, wherein the way of joining the two plates is to add hot air to the transparent substrate surface of the upper plate and the glass substrate surface of the lower plate, respectively. , And a metal bump with a low melting point is used as the conductive and adhesive material. 16. The manufacturing process of the organic light-emitting display substrate as described in Item 10 of the scope of the patent application, wherein the way to join the two plates is to pressurize the substrate and place it on the surface of the transparent substrate on the upper plate, and irradiate it with ultraviolet light. On the surface of the glass substrate of the lower plate, an anisotropic conductive adhesive is used as a conductive and adhesive material. 17. The manufacturing process of the organic light-emitting display substrate as described in Item 10 of the scope of the patent application, wherein the method of joining the two plates is hot pressing on a heater placed on the surface of the transparent substrate of the upper plate, and anisotropic Conductive film as Page 23 514751 VI. Patent application scope Conductive and adhesive material ΙΙϋϋΙ Page 24