TWI283938B - Organic electroluminescent devices and fabrication methods thereof - Google Patents

Abstract

Organic electroluminescent devices are disclosed. A representative device incorporates a substrate that comprises a control area and a sensitive area. A switch device and a driving device are disposed overlying the control area. A photo sensor is disposed overlying the sensitive area. An OLED element is disposed in the sensitive area and illuminating to the photo sensor. A capacitor is coupled to the photo sensor and the driving device, wherein a photo current corresponding to the brightness of the OLED element is generated in the photo sensor responsive to the OLED element illuminating the photo sensor such that a voltage of the capacitor is adjusted by the photo current to control the current passing through the driving device, thus changing the illumination of the OLED element.

Description

1283938 • NEXT DESCRIPTION OF THE INVENTION: TECHNICAL FIELD The present invention relates to a display element, and more particularly to an organic electroluminescence display element and a method of fabricating the same. [Prior Art] Organic electroluminescent devices (also known as organic light emitting diodes (OLED) displays) are based on organic molecular materials (which can be divided into small molecular weights). A small molecule material and a polymer material apply an applied electric field to cause luminescence. Organic electroluminescent devices are light matrix, high contrast, low power consumption, high resolution, and short reaction time because they are self-emission elements' dot matrix type display. (fast _ response time), no need for backlight and wide viewing angle, and its panel size can be displayed from 4mm microdisplay to 1〇〇吋 large outdoor kanban display' as the next generation flat panel display (fjat panei Display, FPD). In addition to the application of the display, the organic electroluminescent element can form an array structure on a thin and flexible material, making it more widely used in applications, especially suitable for illumination. It is generally estimated that if the luminous efficiency of the organic electroluminescent device is increased to more than 1 〇〇 Lm/w, the organic electroluminescent display device has an opportunity to replace the general illumination source. Please refer to Figure 1, a switching transistor 1〇2 controls an organic galvanic 0773-A31696TWF; P93079; wayne 6 1283938 illuminating unit 106, and _drive ^ However 'organic electric excitation light ta% body 1G4 transfer to - Power cord VP. The problem is that there is a illuminating display that has a 昼 phase uniformity that does not cause a decrease in brightness after a long period of operation. [Inventive content] Therefore, in order to solve the μ, +, _ electromechanical excitation light display For the solution, there are more::r ♦ Make organic electroluminescence = _ f month ^, - kind of organic electroluminescence display. In a Jinxin and - drive component is located on the control area, the measurement state is located in the sensing area, and the excitation light unit is located on the sensing area, and is operable to take care of the sensor, a sensor a capacitor coupled to the photosensor and the drive element,

2. The light that is irradiated to the photosensor by the organic f excitation light unit is sensed by the photo sensor to generate a photocurrent corresponding to the organic electroluminescence light unit, so that the voltage of the capacitor is adjusted by the photo current to control the passage. The current of the driving element, therefore, changes the illumination of the organic electroluminescent unit. The present invention provides a method of manufacturing an organic electroluminescent display element. First, a substrate including a control region and a sensing region is provided. Thereafter, an active layer is formed on the control region of the substrate to form a gate dielectric layer on the active layer and the sensing region of the substrate. Next, a conductive layer is formed on the gate dielectric layer, and the conductive layer is patterned to form the first and the first 0773-A31696TWF; P93079; wayne 7 1283938 two gates in the control region, and form a first in the sensing region Three gates. The electrical layer covers at least the first, second, and second portions, and forms a portion of the active layer on the sensing layer. The component element is doped on the active layer of the sensing element, forming a sensing and sensing element. The poles are electrically connected to each other with a sense of f/l!l7L source edge. Thereafter, the two pairs of sensing regions of the two layers of the organic electroluminescent unit are formed. The control area and the [Implementation] of the present invention will be described below with reference to the detailed description of the embodiments. In the illustration or on the same day, the same figure number is used for similar or identical. In the drawings, the β degree of the embodiment may be expanded to simplify or facilitate. "The parts/knife of the illustrated towel element will be described. It will be appreciated that the elements shown or described may have various familiarities. In the form known to those skilled in the art, in addition, when located on a substrate or another layer, the layer may be directly on the substrate or another layer, or may have an intervening layer therebetween. On the substrate, (ovserlying the substrate), on the layer, "(10) just as or, on the film" (reading e running), etc., indicates the relative positional relationship with the surface of the layer, Ignoring the layers present in the middle 'so the above description can be expressed as a non-contact state in which one or more layers are in direct contact with the layer or in between. FIG. 2 is an organic electroluminescent display with compensation elements according to an embodiment of the invention. Schematic diagram of the circuit. Please refer to 帛2, an organic electric 0773-A31696TWF; P93079; wayne 8 1283938 The excitation light display element comprises a halogen unit 20, and in the halogen unit 20, for example, a switch integrated circuit (switch 1C) ) or open The switching element 206 of the transistor is controlled to control the organic electroluminescent display unit 202. The pixel unit 20 also includes a driving element 204 (also referred to as a driving integrated circuit) connected to the power line VP, wherein the current passing through the driving element 204 The illuminance 212 of the organic electroluminescent device 202 can be controlled. The data line 220 controls the switching element 206. Alternatively, a capacitor 208 is connected to the gate of the driving element 204, wherein the capacitor 208 is also coupled. Connected to a photo sensor 210, in addition, the voltage of the capacitor 208 can be adjusted to control the current through the driving element 204 according to the illuminance 212 of the organic electroluminescent unit 202 sensed by the photo sensor 210, thus, The illuminance 212 of the organic electroluminescent device 202 can be changed as a compensation. FIG. 3N is a cross-sectional view showing an organic light emitting unit according to an embodiment of the present invention, and FIGS. 3A to 3N are diagrams showing organic light emission according to an embodiment of the present invention. Referring to FIG. 3A, firstly, a φ-substrate 3〇2 is provided. The substrate includes a control region 3〇4, a sensing region 3〇6, and a capacitor region 307. Forming a buffer layer 308, the buffer layer 308 may be composed of tantalum oxide, tantalum nitride or hafnium oxynitride. In a preferred embodiment of the invention, the buffer layer 308 is a stacked layer of tantalum oxide and tantalum nitride. The thickness of the layer may be, for example, about 350 to 650 angstroms of tantalum nitride and about 1000 to 1600 angstroms of yttrium oxide. Next, a conductive layer (not shown) is formed on the buffer layer, and the conductive layer may be composed of a polysilicon. For example, the conductive layer may first deposit an amorphous germanium by chemical vapor deposition, followed by excimer laser annealing 0773-A31696TWF; P93079; wayne 9 1283938 • (Excimer Laser Annealing, hereinafter referred to as ELA) It is converted into polycrystalline germanium. Thereafter, the conductive layer is defined by a conventional lithography and etching method as a first active layer 310 and a second active layer 312 over the control region 304 of the substrate 302, and a lower electrode 309 is formed over the capacitor region 307 of the substrate 302. The active layer is not retained on the sensing region 306. Thereafter, as shown in FIG. 3B, the second active layer 312 is covered by a photoresist 314, and the first active layer 310 is subjected to a channel implantation step 316 (channel doping), which is preferred in the present invention. In an embodiment, the implantation step 316 can implant B + and the doping amount can be 0 to 1 E13/cm 2 . Subsequently, please refer to FIG. 3C, and another photoresist 318 is formed to cover the channel region 320 of the first active layer 310, and then N+ ions 322 are implanted to form the source 324 and the gate 326 of the N-type transistor. In a preferred embodiment of the present invention, the implanting step 322 can implant phosphorus, and the doping amount can be 1E14~1E16/cm2. Referring to FIG. 3D, the photoresist is removed and a gate dielectric layer 328 is deposited on the first active layer 310, the second active layer 312, the buffer layer 308, and the capacitor region 307. On the lower electrode 309, the gate dielectric layer 328 may be composed of tantalum oxide, tantalum nitride, hafnium oxynitride, a combination thereof or a stacked layer thereof, or other high dielectric materials. It should be noted that the gate dielectric layer 328 is used as a capacitor dielectric layer in the capacitor region 307. Subsequently, please refer to FIG. 3E to deposit a gate conductive layer (not shown) on the gate dielectric layer 328, and the gate conductive layer may be doped polysilicon or metal, in a preferred embodiment of the present invention. For example, the gate conductive layer may be Mo having a thickness of about 1500 to 2500 angstroms. 0773-A31696TWF; P93079; wayne 10 1283938 Next, the gate conductive layer is patterned by conventional lithography and residual method. 'a N-type transistor is formed over the first active layer 310: 330' in the second active layer A P-type transistor gate 332 is formed over 312, and a sensing dielectric idler 334 is formed on the gate dielectric layer of the sensing region 306, and an upper electrode 335 is formed on the capacitor region 3?7. The pole 309, the gate dielectric layer 328 and the upper electrode 335 constitute a capacitor 208 as shown in FIG. In a preferred embodiment of the present invention, after forming the gates 330, 332 and 334, a light doping step can be performed, for example, by ion implantation, in an N-type transistor 2〇6. A lightly doped region 336 is formed on both sides of the first active layer 31 and the channel region 320. Thus, the N-type switching elements 206 and P shown in FIG. 2 are formed in the control region. A driving element 2〇4, in one embodiment of the invention; the switching element 206 and the driving element; 2〇4 are upper gate transistors. Subsequently, please refer to FIG. 3F, forming a photoresist 338 to cover the first main φ moving layer 310, and performing an ion implantation step 34 (such as implanting p-type dopant) to be in the p-type transistor gate. The source 344 and the gate 346 of the P-type transistor are formed on both sides of the channel region 342 below the pole 332. In this step and the above-mentioned body building step, the structural layer under the sensing element gate 334 of the sensing region 306 is The sensing element gate 334 is shielded from forming dopants therein. Next, referring to FIG. 3G, the photoresist is removed, and a dielectric layer 348 is deposited on the drain dielectric layer 328, the N-type transistor gate 330, and the P-type transistor of the control region 304. Gate 332, sensing region 3〇6 0773-A31696TWF; P93079; wayne 11 1283938 • sensing element gate 334, and capacitor region 307 above electrode 335. The dielectric layer 348 can be used as a metal interconnect layer for the control element (eg, an N-type transistor or a P-type transistor) in the control region 304, and can be used as a sensing element in the sensing region 306. Gate dielectric layer. The dielectric layer 348 can determine its composition and thickness according to the requirements of the product or the process requirements. For example, the dielectric layer 348 can be composed of tantalum oxide, tantalum nitride, hafnium oxynitride, a combination thereof, or a stacked layer thereof. The dielectric layer 348 may in turn be a low dielectric material, such as polypyrene (p〇iyimide), rotating glass (SOG), diamond-like carbon (for example, &lack developed by American Applied Materials)

Diamond), Fluorite Glass FSG, SILKTM developed by Dow Chemical, OrionTM developed by Trikon Technologies,

FLARETM developed by Honeywell, LKD, Xerogel, Aerogel, polycrystalline fluorinated carbon and/or other materials developed by JSR Micro' can be high dielectric materials such as Ta2〇5, Hf02, Al2〇 3,

In02, La203, Zr〇2, Ta02, telluride, aluminide and the above-mentioned metal φ oxide oxynitride, and perovskite-type 〇xide. In a preferred embodiment of the present invention, the dielectric layer 348 is a stacked layer of tantalum oxide and tantalum nitride, more preferably a tantalum nitride/yttria/tantalum nitride stack structure, wherein the thickness of the lower tantalum nitride layer It is about 2500~3500 angstroms, the thickness of yttrium oxide is about 2500~3500 angstroms, and the thickness of the upper layer of tantalum nitride is about 5 〇〇~15 〇〇. Next, referring to FIG. 3H, a sensing element active layer 35A and a sensing element doping layer 352 are formed on the dielectric layer 348 of the sensing region 306. In one embodiment of the invention, the sensing element is The active layer 350 may be based on 〇 773.A31696TWF; P93079; wayne ^ !283938 semiconductors (eg, polycrystalline germanium, single crystal germanium, germanium germanium, and/or germanium), composite semiconductors (eg, tantalum carbide, and/or arsenic), Alloy semiconductors (e.g., SiGe, GaAsP, AlIns, A1GaAs, such as good and domain Gainp, in the preferred embodiment of the invention, the sensing element active layer 35 is composed of no: amorphous amorphous germanium) The doping layer M2 of the measuring element is composed of a doping composition. Thus, the active layer of the sensing element, and the irradiation of the organic electroluminescent light unit formed by the step are more sensitive. The bulk layer of the body material may be the active layer 350 of the sensing element. For the (four) layer of the main material, preferably, the sensible core is doped with amorphous slabs and the sensing element doped layer is 35g... N+ ionic amorphous dream, better, sensing ^ is thickness The doping is about 1000 angstroms to 10,000 angstroms, and the sensing element: the thickness of the active layer 350 is about 100. Å ~ 1000 angstroms. 4 beach layer 352 thickness is about the latter 'Please refer to Figure 31, to transfer the patterned dielectric layer 348 and gate dielectric exhibition, the vapor and the name of the private, 354 respectively exposed N The source of the transistor is only 328, forming a plurality of openings 326, and the source 344 4 of the P-type transistor, the gate and the gate for the subsequent metal wire connection. The pole 332 and the drain 346 are connected. Next, please refer to the 3J figure, the blanket cover # shows), and then deposit a metal layer with the conventional yellow light and eclipse I (the two sides of the undoped layer 352 are respectively formed to be sensitive to the sensing element The impurity layer 352 is used to form the metal layer 356, and simultaneously form a conductive contact element in the sensing opening of the sensing region 306. 350 and sensing element source 358 and sensing 0773-A31696TWF; P93079; wayne 13 1283938 • element drain 360, thus forming the light sensing element 210 of FIG. 2, for example, the light sensing element 210 can For example, a gate type transistor is used. In some embodiments of the invention, the switching element 206, the driving element 204, and the light sensation The device 210 may include a gate on the same layer. For example, referring to FIG. 3J, the gate 330 of the switching element, the gate 332 of the driving element, and the gate 334 of the photo sensor are in the same layer. Referring to FIG. 3K, a protective layer 362 is formed on the conductive contact 356, the dielectric layer 348, the sensing element source 358, and the sensing element drain 360. The protective layer 362 may be composed of tantalum nitride or hafnium oxynitride. Preferably, the protective layer 362 is composed of tantalum nitride having a thickness of about 1000 angstroms to 5000 angstroms. Next, referring to FIG. 3L, a planarization layer 364 composed of, for example, an organic material or yttrium oxide is formed on the protective layer 362. In the preferred embodiment of the invention, the thickness of the planarization layer 364 is approximately 10000 angstroms to 50,000 angstroms, and in a subsequent step, the planarization layer 364 and the underlying protective layer 362 are patterned in a conventional yellow light and etching process to form contact openings 366 over the conductive contacts 356 described above, In a preferred embodiment of the invention, the contact opening 366 exposes the conductive contact 356 above the drain 346 of the P-type transistor. Subsequently, referring to FIG. 3M, a halogen electrode layer 368 such as indium tin oxide (hereinafter referred to as ITO) is formed on the planarization layer 364 and electrically connected to the conductive contact 356. Thereafter, a pixel defining layer 370 0773-A31696TWF, such as an oxide or an organic material, is formed; P93079; wayne 14 1283938 is on the partial planarization layer 364 and the halogen electrode layer 368, in particular, the halogen defining layer 370 is exposed. Some or all of the sensing elements. Subsequently, referring to FIG. 3N, an organic electroluminescent layer 372 is formed over the above-described pixel electrode layer 368 and the halogen defining layer 370. In an embodiment of the present invention, the organic electroluminescent layer 372 is disposed on the halogen electrode layer 368 (also referred to as an anode conductive layer), including a hole injection layer, a hole transmission layer, and an organic layer. a luminescent material layer, an electron transport layer, a Lu-electron injection layer, and a cathode conductive layer. Among them, the anode conductive layer is made of indium tin oxide (In2〇3:Sn, abbreviated as ITO), which has the advantages of easy etching property, low film formation temperature, and low resistance. After a bias voltage is applied, the electrons and the holes are respectively passed through the electron transport layer and the hole transport layer into the organic light-emitting material layer and combined to form an excitation photon (exciton), and then the energy 1 is released and returned to the ground state ( Ground state), and in these released energy, it will be released in different color light depending on the selected luminescent material, for example: red light (R), green light, blue light (B) . The wind then 'forms a cathode 374 having a high reflection coefficient such as aluminum or silver on the organic electroluminescent layer 372. Thus, the halogen electrode layer 368, the organic electroluminescent layer 372 and the cathode 374 constitute an organic electrical excitation. The light unit, as shown in FIG. 2, forms a downwardly-emitting organic electroluminescent element 202, as shown in Figures 2 and 3N, in some embodiments of the invention, when the organic electroluminescent unit '202 When the light sensor 210 is irradiated, a photocurrent is generated in the photo sensor 210, and the organic electroluminescence excitation unit 202 is 0773-A31696TWF; P93079; wayne 15 1283938. The brightness system determines the magnitude of the photocurrent, and therefore, the light can be determined according to the light. The illuminance of the organic electroluminescent light unit 202 sensed by the sensor 210 adjusts the voltage coupled to the capacitor 208 of the driving element 204 to control the current through the driving element 204. Thus, the illuminance of the organic electroluminescent light unit 202 can be changed. As a compensation. Therefore, after the organic electroluminescent device is degraded, the brightness uniformity of the organic electroluminescent unit 202 can be improved by the internal compensation described above.

I Fig. 4 shows that a halogen unit 20 (for example, a halogen unit shown in Fig. 2 or Fig. 3N) can be incorporated into a panel (e.g., panel 30), and the panel can be an organic electroluminescent panel. In addition, the panel can be implemented as part of various types of electronic components (eg, electronic component 50). In general, the electronic component includes the organic electroluminescent panel 20 and the input unit 40. Further, the input unit 40 is operatively coupled to the organic electroluminescent panel 30 and provides an input signal (eg, a surface signal). For example, the electronic component 50 can be a personal assistant (PDA), a notebook computer, a desktop computer, a mobile phone, a car TV (car TV), or a digital camera. While the present invention has been described in its preferred embodiments, the present invention is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application. [Simple description of the diagram] Fig. 1 reveals that there is a problem of poor uniformity between the organic electroluminescent display panel and the substrate 0773-A31696TWF; P93079; wayne 16 1283938. Fig. 2 is a circuit diagram showing an organic electroluminescent display having a compensating element according to an embodiment of the present invention. 3A to 3N are cross-sectional views showing a process medium for forming a sensing element compensation organic light emitting element according to an embodiment of the present invention. Fig. 4 is a schematic view showing an electronic component of an embodiment of the present invention.

[Main component symbol description] VP ~ power line; 20 ~ halogen unit; 30 ~ panel; 40 ~ input unit; 50 ~ electronic components; 102 ~ switch transistor; 104 ~ drive transistor, 106 ~ organic electroluminescent unit 202~organic electroluminescent display unit; 204~ drive element; 206~switch element; 208~capacitor; 210~photo sensor; 212~illuminance; 302~substrate; 3 04~ control area; 306~ sensing area , 307 ~ capacitor region, 3 0 8 ~ buffer layer; 309 ~ lower electrode; 310 ~ first active layer; 312 ~ second active layer; 314 ~ photoresist; 316 ~ channel implantation step; 318 ~ photoresist; ~ channel area; 322~N + ion; 324~ source; 326~dip; 0773-A31696TWF; P93079; wayne 17 1283938 328~ gate dielectric layer; 330~N type transistor gate; 332~P type Transistor gate; 334~ sensing element gate; 335~ upper electrode; 344~P type transistor source; 346~P type transistor drain; 348~ dielectric layer; 350~ sensing element active Layer; 352~ sensing element doped layer; 354~ opening; 356~ Electrical contact; 3 5 8~ sensing element source, 3 6 0~ sensing element> and pole, 362~ protective layer; 364~ planarization layer; 366~ contact opening; 368~ 昼 element layer; 370~ Alizarin defined layer; 372~organic electroluminescent layer; 374~ cathode.

0773-A31696TWF; P93079; wayne 18

Claims (1)

1283938 X. Patent application scope: 1. An organic electroluminescence display element, comprising: a monolithic unit, comprising: a substrate comprising a control area and a sensing area; a switching element and a driving element located at a light sensor on the control area is located on the sensing area; a shoulder 狨% illuminating soap element is located on the sensing area, and the photo sensor is; and... a capacitor is coupled to the a light sensor and the driving element, wherein the light emitted by the organic galvanic light to the photo sensor is sensed by the photo sensor, and a photocurrent of a pair of ..., a unit is generated, so that the light is two; Electromechanical excitation light [to control the illuminance of the electro-optic excitation light unit of the capacitor through the driving element; thus, changing the range of the organic component: the organic electroluminescence light shown in item 1 shows 兮, to open 70 pieces and The driving element is an upper open-pole, and the photo sensor is a lower gate transistor.有机 Element X: The organic electroluminescent light shown in the sub-paragraph includes a second active layer, and the two layers of the driving element layer are polycrystalline germanium layers. A active layer and the second active 0773-A31696TWF; P93〇79; wa^e 1283938 a 5. The organic electroluminescent display element according to item 1 of the patent application scope, wherein the optical sensing has a first A three active layer, and the third active layer is an amorphous fracture layer. The organic electroluminescent display device of claim 1, further comprising: a first active layer located in the switching element; a second active layer located in the driving element, and A gate dielectric layer is disposed on the first active layer, the second active layer, and the sensing region. 7. The organic electroluminescent display device of claim 4, wherein: the first gate and the second gate are located on a gate dielectric layer of the control region, wherein the first gate a pole is located in the switching element, and the second gate is located in the driving component; and a third gate is located on the gate dielectric layer of the sensing region, wherein Lu. The pole, the second pole, and the third pole are the same layer. = The organic electric excitation θ light described in item 7 of the patent application is 7Γ*? w άι Jl-r · The third layer of a dielectric layer And at least covering the first interpole, the second gate, and the third active layer on a portion of the dielectric layer of the sensing region. The organic electro-excitation described in item 8 of the component HI patent scope Light-displaying a sensing element doped layer on the third active layer; and 〇 773.A31696TWF; P93079; wayne 20 1283938 sensing element source and a sensing element are non-polar, respectively electrically connected to the sensing element The opposite side of the doped layer. 10. The organic electroluminescent display element as described in claim 6 of the patent application, The dielectric layer further includes a plurality of openings exposing the first gate, the second gate and portions of the first and second active regions, and the openings are filled with conductive contacts. The organic electroluminescent excitable component of claim 10, further comprising a protective layer disposed on the conductive contact, the dielectric layer, the source of the sensing component, and the drain of the sensing component. The organic electro-active excitation device of the above-mentioned item, further comprising: a first electrode located on the planarization layer; an organic electroluminescence layer disposed on the first electrode; and a second electrode located at The organic electroluminescent light layer, wherein the organic electroluminescent light layer and the second electrode constitute the organic electroluminescent light 7G earlier. And input to the 0773-A31696TWF; P93079; wayne 21 1283938 15 · as shown in the patent application scope component, further comprising: 13 organic electroluminescent excitation: device for input to the display panel. 1. For example, the organic electroluminescence light described in the patent scope 帛13 J page is a part of the display element. An organic electroluminescent display element comprises: a substrate comprising a control region and a sensing region; a switching element and a “driving element” located on the control region; a light sensing state located in the sensing region An organic electroluminescent unit located in the sensing region and operable to illuminate the photo sensor; and, a capacitor 'reduced to the photo sensor and the driving element, wherein The photo-sensing H-electro-mechanical excitation light unit is irradiated to the photo-sensing nm to generate a photocurrent corresponding to the organic electric (four) optical unit, and thus, the photocurrent is adjusted by the photocurrent to control the passage of the _ The illuminating current, therefore, the illuminance of the organic electroluminescent unit, wherein the switching element is an upper gate transistor, and the photo sensor is a lower gate transistor. 18. A method of fabricating an organic electroluminescent display device, comprising: providing a substrate comprising a control region and a sensing region; forming an active layer on the control region of the substrate; forming a gate dielectric layer Forming a conductive layer on the gate dielectric layer; forming the conductive layer to form first and second gates 0773-A31696TWF in the control region; P93079; wayne 22 And forming a third gate in the sensing region, forming a dielectric layer covering at least the first, second, and third gates; forming a portion of the sensing element active layer on the sensing region Forming a sensing element doped layer on the active layer of the sensing element; forming a pair of sensing element source and sensing element drain electrically connected to the sensing element doping layer respectively Side, and Forming an organic electroluminescent light sheet 〉 then region f-. 70 in part of the control area and the sense 0773-A31696TWF; P93079; wayne 23