TW577107B - Thin film transistor panel used in transflective liquid crystal display and its manufacturing method - Google Patents

Abstract

The present invention is related to a kind of thin film transistor (TFT) panel used in transflective liquid crystal display (LCD). The invention is featured with having an etch stop pattern containing the first part right opposite to the channel region of a TFT and the second part right opposite to the electrode of the first capacitor. The second part of the etch stop pattern has a wavy shape surface, so that the electrode surface of the second capacitor disposed on it has a wavy shape for use as the surface that reflects the environment light. In addition, the invention also provides the method for manufacturing TFT panel.

Description

577107 V. Description of the Invention (1) [Field of the Invention] The present invention relates to a thin film transistor (TFT) panel and a method for manufacturing the same, and particularly relates to a trans fleet (trans fleet) Thin film transistor panel of IVE) type liquid crystal display and manufacturing method thereof. °° Λ [Previous technology] Liquid crystal displays can be classified according to their illumination light sources. A reflective liquid crystal display illuminates the display with an external light source (ambient light) coming in from its front side (near the observer side). A reflective surface (such as an aluminum or silver reflector) is generally provided in or on the back of the reflective display device, which reflects light to illuminate the reflective display device. Although the reflective display meets the requirements of low power consumption, ^ ° the image is often dark and difficult to view. In addition, there are many times when the external light source ^ is not enough, so there are many restrictions on the use of pure reflective displays. 1 When the intensity of the external light source is not enough to view the image, auxiliary (such as a backlight module) is often used Lai Shun bright the display. Although the source of the unbounded light source, the auxiliary light source can illuminate the display, but it consumes a lot of extravagance 'Generally speaking, the battery of a portable computer can be used twice' f2 source needs to be charged after 2 to 4 hours . And in the external environment, the light source is too strong (such as under the outdoor sun) 'will also make it difficult to identify the "transmi ssi ve" image lit by the backlight alone because of insufficient contrast. In order to overcome the lack of the aforementioned reflective displays and transmissive & displays, some electronic displays have been designed to use a backlight source when the external light source is sufficient, and the backlight source is only activated when the external light source is insufficient. The same $ make

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A design with dual functions of reflection and penetration is called "transflective." The semi-transparent and semi-reflective display is a dual-mode, semi-transparent, semi-transparent, and dual-mode display. It uses a crystal display 7 in the reflective mode, and uses the built-in backplane to mount it in the transmissive mode. Ambient Light Source is currently the main manufacturer of liquid crystal display devices and panels. Thin-film transistor-based technology. As is well known, this technique is based on amorphous stone. The display device generally includes a thin-film transistor panel, a conventional liquid crystal and a liquid crystal layer sandwiched therebetween. The color filter panel is conventionally manufactured by firstly depositing one to one film with etching process and capacitor electrodeposition on the surface of the part, and sequentially depositing the film process on the surface of the film process) and a transflective liquid crystal The display method will be described below with reference to FIGS. I to 7. Body Panel

The first metal layer is sputtered on a transparent glass substrate 100: the thickness is set in advance, and the first metal layer is sharpened to form a gate electrode 110 and a gate circuit (not shown in the figure, the electrode 120 is on the substrate 100) . Referring to FIG. 2, the insulating layer 13 has a substrate of the gate electrode 110, the gate line, and the capacitor electrode 120. Then, an amorphous silicon layer 140 and an etch stop layer 130 are formed, and The etch stop layer is formed by a second micro-etch to form an etch stop 150 facing a channel region (channe. An impurity-doped amorphous silicon layer (for example, n + doped amorphous number, a second metal layer is sequentially deposited on The entire surface of the substrate is formed by etching the amorphous silicon layer 140, n +, and the second metal layer with a third lithography process. See FIG. 3, the amorphous silicon patterns u0a, n + Doped amorphous silicon pattern 160 and metal pattern include data lines (not shown in the figure), a source 1 7 0 a and a drain 1 7 0 b separated by a channel 1 6 5 and electrical

Page 6 577107 V. Description of the invention (3) Capacitive electrode 1 7 0 c. Then it will be patterned until it is patterned (see the first through the fifth through the fifth with a full surface, and the positive light is shown in Figure 6), (see the previous seven passages, therefore, its invention can overcome [Invention of the invention The simplified process of the film of the present invention is to reach a reflective liquid-protective layer 180 formed on the entire surface of the structure shown in FIG. 3 with a predetermined thickness. The protective layer is hidden by a fourth lithography process. Part of the electrode 170b and the capacitor electrode i70c are exposed (Fig. 4). Then, an indium tin oxide layer (ITO layer) 190 with a bright conductive layer is formed on the entire surface with a protective layer pattern, and the ITO layer is patterned by a lithography process (see FIG. 5). An organic layer such as a positive photoresist layer 192 is formed on the structure shown in FIG. 6 until it has a predetermined thickness. A sixth lithography resist layer 192 is patterned and has a wavy surface (see 'Finally, a reflective metal layer 194 is formed on the structure surface shown in FIG. 6. A seventh lithography process is used. See Figure 7 for the reflective metal layer (see Figure 7). Because of this conventional thin-film transistor panel manufacturing method to Λ

The photomask manufacturing process is completed, the manufacturing process is complicated, the yield is low, and the manufacturing cost is high when the manufacturing is increased. Therefore, an improved method for manufacturing a thin film liquid crystal panel is provided, or at least the problems of the foregoing prior art are improved. The object of the invention is to provide a liquid crystal display panel for a transflective and transflective liquid crystal display and a manufacturing method thereof, which can reduce the mask manufacturing process and increase the yield. , And other objects, the present invention provides a thin film transistor panel for a semi-transmissive semiconductor display, which is characterized by having a

Page 7 577107 V. Description of the invention (4), the etching stop pattern includes a first portion facing a channel region of a thin crystalline transistor and a second portion facing a first capacitor electrode. The second part of the I-etched resist pattern has a wavy surface so that the surface of the second capacitor electrode disposed thereon is wavy for use as a reflective surface. The present invention provides a method for manufacturing the thin film transistor panel, which mainly includes the following steps. First, a gate electrode and a first capacitor electrode are formed on an insulating substrate (for example, a transparent glass substrate). After that, a gate insulation layer is deposited to cover the gate line. On the gate insulating layer, a semiconductor layer (such as an amorphous stone layer) and a coin-cutting layer (such as a II fossil layer) are deposited, and the etch stop layer is patterned to form the etch stop pattern. Then, an ohmic contact layer and a conductive layer are continuously formed to cover the semiconductor layer and the etch stop pattern, and the semiconductor layer, the ohmic contact layer, and the conductive layer are patterned to form a semiconductor pattern, an ohmic contact pattern, and a conductive pattern. . The conductive pattern includes a source separated by the channel, a drain electrode, and a second capacitor electrode formed directly above the wavy surface of the etch stop pattern H,... So that the surface of the second capacitor electrode is wavy. Finally, a protective layer pattern and a transparent conductive pattern are formed on the conductive pattern to form a transparent pixel electrode. In the thin film transistor panel manufactured according to the above method, the second capacitor electrode system and the first capacitor electrode form a storage capacitor unit. In addition, the second capacitor electrode is barely exposed on the transparent conductive pattern as a reflective surface. Therefore, the liquid crystal display made of the thin film transistor panel of the present invention has a design with dual functions of reflection and transmission. It is worth noting that the design of the second capacitive electrode system as a reflective electrode and the source / drain electrode of the present invention

577107 V. Description of the invention (5) * Formed in the same lithography process; In addition, the wavy surface of the second capacitor electrode is formed by etching the wavy surface of the second part of the resist pattern, and the wavy surface of the second capacitor electrode is formed. The second part is formed in the same lithography process as the first part in the TFT channel region. Therefore, the method for manufacturing a thin film transistor panel according to the present invention can be completed with only five photomask processes, thereby simplifying the process and improving yield. Other objects, advantages, and novel features of the present invention will be clearer from the following detailed descriptions associated with the drawings: [Explanation of the Invention] Although the present invention may be embodied in different forms of embodiments, those shown in the drawings The following description is a preferred embodiment of the present invention. Please understand that the present disclosure is considered as an example of the present invention and is not intended to limit the present invention to the illustration and / or description. In a specific embodiment. A method for manufacturing a thin film transistor panel according to an embodiment of the present invention is described below with reference to FIGS. 8 to 13. First, a metal layer is sputtered on a bright substrate 200 (for example, a transparent glass substrate) until it has a predetermined thickness, and then the first metal layer is patterned using a first lithography process to gate electrode 210 and a capacitor The electrode 220 is on the substrate 200 (see FIG. 8). Although not shown in the figure, when the gate electrode 210 and the capacitor electrode 220 are formed, a gate line connected to the gate electrode is also formed at the same time. Referring to FIG. 9, an insulating layer (such as a silicon nitride (SiNx) layer) is deposited on the entire surface of the structure shown in FIG. 8 to form a gate insulating layer 230. Then, a semiconductor layer such as an amorphous stone layer 2 40 and a resist layer 2 50 (such as a silicon nitride (SiNx) layer) are sequentially deposited on the gate insulating layer 2 3 0

577107 V. Description of the invention (6), and the etch stop layer 2 50 is etched by a second lithography process to form an etch stop pattern (see FIG. 10), which includes a first portion 250a A channel region of a thin film transistor structure and a second portion 250b are opposite to the capacitor electrode 220, wherein the second portion 250b has a corrugated surface. The etch stop pattern can be patterned with a photoresist pattern 2 5 4 as shown in FIG. 9. The photoresist pattern 2 5 4 used here includes a first portion 2 5 4 a facing the channel region, a second portion 254b with a wavy surface facing the capacitor electrode 220, and a photoresist having substantially no photoresist. Part III. In detail, in the second lithography process, the photoresist pattern 2 5 4 is used as an etch mask, and the etching stopper layer 2 5 is etched to expose the non-conductive layer under the third part of the photoresist pattern 2 5 4. Crystal silicon layer 2 4 〇. According to an embodiment of the present invention, the photoresist pattern 2 5 4 is obtained through the following steps. First, referring to FIG. 9 ', a photoresist layer 2 52 is formed on the etch stop layer 250. Then, a photomask 256 having a predetermined pattern is placed on the photoresist layer 252. The photomask 2 5 6 has a plurality of slits 256a (only two slits are shown in FIG. 9). 2 5 2 Exposure to light source. Finally, the exposed light ^ and layer 2 5 2 are developed to obtain a photoresist pattern 2 5 4, wherein the photoresist pattern 2 5 4 is 4 points 254b has at least one recessed portion corresponding to the narrow d 5 of the photomask 256 6 a. On this evening, ^ • 左 丄 +, also. r The wavy surface portion I of the second part of the blocking pattern 2 5 0 b is formed by the half-exposure step. The wavy surface of the second etching resist pattern:> 2 50 b can effectively improve the reflection efficiency of the reflective electrode to be formed thereon. Holding the ohmic contact layer, such as

Page 10 577107 V. Description of the invention (7). Impurity-doped layer (such as η + doped amorphous silicon layer) and a second metal layer are sequentially deposited on the entire surface of the structure shown in FIG. 10. The amorphous lithographic pattern 2 4 0 a is formed by using the third lithography clothing Xin Ren's engraved δ Xuanfei Japanese and Japanese stone layer 2 4 0, η + doped amorphous > 5x layer and the second metal layer. η + doped amorphous stone pattern 260, a source electrode 270a / drain electrode 270b and a capacitor electrode 270c separated by a channel 265 (see FIG. 11). Although not shown in the figure, in the above steps, a data line connected to the source is also formed at the same time. It is worth noting that the capacitor electrode 27 o c is formed directly above the wavy surface of the first part of the etch stop pattern 2 50 b so that the surface of the capacitor electrode 27 o c is wavy. In detail, in the third lithography process, a predetermined photoresist pattern is used as an etching mask, and the amorphous silicon layer 2 40, the n + doped amorphous silicon layer, and the second metal layer are etched and exposed. On the gate insulation layer 230, a channel 2 65 is formed to separate the source electrode "and the drain electrode", wherein the amorphous silicon layer under the channel 2 65 is protected by the first part of the etching stopper pattern 250a. Roughly intact. A protective layer 280 (such as a nitrided layer, not shown in the figure) is formed on the entire surface of the structure described above, up to a predetermined thickness. A fourth lithography process is used to pattern the protective layer to form a through hole 280a that exposes the drain electrode 27 and a through hole 280b that exposes the capacitor electrode 270 (: wavy surface through hole 280b (see FIG. 12). Referring to FIG. 13, an indium tin oxide layer j ITO / layer as a transparent conductive layer 29 is formed on the entire surface of the structure shown in FIG. 12, and the IT0 layer is patterned by a fifth lithography process. In this way, a transparent conductive pattern is formed to be electrically connected to the drain electrode 27Ob through the through hole 28o and electrically connected to the capacitor electrode 27oc through the through hole 28ob.

577107 V. Description of the invention (8) As shown in the figure, the capacitor electrode 2 70c has a wavy surface. Tian and Tian ^ are used to increase the reflectivity in the direction of non-specular reflection angle. It can be understood that the wavy surface of Xi + & + pole 2 7 0 c is not limited to 辂 内 谷 电 shown in Figure 13; 鄢 (that is, 1 has a concave or convex surface). 〃 In the thin-film transistor panel made according to the above method (from the figure below), the capacitor electrode 270c is formed with the capacitor electrode 2 2 0-a bet # + & unit for Within a predetermined day after the crystal (TFT) is turned off, the voltage dimension of the pixel electrode formed by the transparent conductive layer is within the range of $ —. In addition, the capacitor electrode 2 70c is substantially exposed on the transparent conductive pattern as a reflective surface. · Thus, the liquid crystal display manufactured by using the thin film transistor surface I of the present invention, when transparent, the transparent conductive material is fully used; and the pixel electrode can allow the light generated by the backlight to penetrate; k 'The capacitor electrode 27 0 c can reflect incident light from an external light source. It is worth noting that the capacitor electrode 2 70_ designed as a reflective electrode in the present invention is formed in the same lithography process as the source electrode 270a / drain electrode 270 b; in addition, the wavy surface of the capacitor electrode 2 70c is blocked by etching The first part of the pattern:-is formed by the wavy surface of the part 2 5 0 b, and the second part 2 5 0 b with the wavy surface is in the same lithography process as the first part 2 5 0 a in the TFT channel region Middle formation. Therefore, the method for manufacturing a thin-film transistor panel according to the present invention can be completed by only five mask processes, thereby simplifying the manufacturing process and improving yield. Although the present invention has been disclosed in the foregoing preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore the guarantee of the present invention

577107 V. Description of Invention (9) * The scope of protection shall be determined by the scope of the attached patent application. iiiii Page 13 577107 Brief description of the diagrams. [Illustration] Figures 1-7 are sectional views showing the manufacturing steps of a conventional thin film transistor panel; and Figures 8-1 3 are sectional views The diagram illustrates the manufacturing steps of a thin film transistor panel according to an embodiment of the present invention. Description of drawing number] 1 100 substrate 110 120 capacitor electrode 130 140 amorphous silicon layer 140a 150 insect resistance 160 165 channel 170a 170b drain 170c 180 protective layer 190 192 positive photoresist layer 194 200 transparent substrate 210 220 capacitor electrode 230 240 non Crystalline silicon layer 240a 250 1 Insect-resistant barrier layer 2 5 0a 2 5 0b Second part 252 254 Photoresist pattern 2 54a 2 54b Second part 256 2 5 6a Slot 260 265 Channel 2 70a Gate electrode insulation layer amorphous Pattern n + doped amorphous silicon pattern source relay capacitor electrode indium tin oxide layer reflective metal layer gate electrode gate insulating layer amorphous pattern first part photoresist layer first part photomask n + doped amorphous silicon Pattern source

Page 14 577107 Brief description of the drawing 2 7 0 b Drain 2 80 Protective layer 2 8 0 b Through hole 2 7 0 c Capacitive electrode 2 80a Through hole 2 90 Transparent conductive layer

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Claims (1)

577107 6. Scope of patent application 1. A method for manufacturing a thin-film transistor panel for a transflective liquid crystal display, including the following steps: forming a gate electrode and a first capacitor electrode on an insulating substrate; forming A gate insulating layer covers the gate electrode and the first capacitor electrode; a semiconductor layer is formed to cover the gate insulating layer; a #etching stop pattern (etching stop pattern) is formed on the semiconductor layer, and the single-cut blocking pattern is formed Including a first part facing a channel region and a second part facing the first capacitor electrode, wherein the second part has a corrugated surface; an ohmic contact layer is continuously formed to cover The semiconductor layer and the etch stop pattern, and a conductive layer covering the ohmic contact layer; patterning the semiconductor layer, the ohmic contact layer, and the conductive layer to form a semiconductor pattern, an ohmic contact pattern, and a conductive pattern, the The conductive pattern includes a source electrode, a drain electrode, and a second capacitor electrode separated by the channel. The wavy surface of the second part of the barrier pattern is directly above the wavy surface of the second capacitor electrode; a protective layer is formed to cover the conductive pattern; the protective layer is patterned to form a first channel that exposes the drain electrode A hole and—a second through hole exposing the wavy surface of the second capacitor electrode; and—, forming a transparent conductive pattern electrically connected to the via via the first through hole = the second through hole electrically connected to the The second capacitor electrode, wherein the wavy surface of the A-valley electrode is substantially exposed on the transparent conductive pattern Hongtian as a reflective surface. ‘Yes 577107 6. Scope of patent application ^ 2. The method for manufacturing a thin-film transistor panel for a transflective and transflective liquid crystal display according to item 1 of the scope of patent application, wherein the step of forming the etch stop pattern includes: forming an etch stop layer Covering the semiconductor layer; forming a photoresist pattern on the etch stop layer, the photoresist pattern including a first portion facing the channel region, and a second portion having a wavy surface facing the first capacitor An electrode and a third portion having substantially no photoresist; and etching the etch stop layer using the photoresist pattern as a mask to form the etch stop pattern. 3. The method of manufacturing a thin-film transistor panel for a transflective and transflective liquid crystal display according to item 1 of the scope of the patent application, wherein the photoresist pattern forming step includes: forming a photoresist layer on the etching resist layer ; Placing a photomask with a predetermined pattern on the photoresist layer, having at least one slit, and exposing the photoresist layer to a light source; and developing the exposed photoresist layer to obtain the photoresist pattern . 4. The method for manufacturing a thin-film transistor panel for a transflective liquid crystal display device according to item 2 of the scope of the patent application, wherein the etching stop layer is a silicon nitride layer. Page 17 577107 6. Application scope of patent, 5. The method for manufacturing a thin-film transistor panel for transflective liquid crystal display according to item 2 of the scope of patent application, wherein the second part of the etching stop pattern has a concave Or the convex portion is provided on the wavy surface. The device with a thin facet crystal film shows a semi-transparent liquid crystal transflective penetrating half. The base of the board should be insulated with a capacitor, and the board should be electrically insulated first. And the above picture is based on the layered electrode edge conductive semi-conductive gate, which should be covered in the case, the layered layer, the insulator, the barrier, and the conductive gate, and the gate ##. In the case of the case, there is no part list and two forms. The first wave source and the first one have an open area with a separate channel. The pass is connected to the second part. The polar electricity, the conductance, the capacity, the envelop, the positive fractal body, the wave conductance, the second wave and the half wave are shown in the case and the diagram. The resistance is etched, the conductivity is etched, and the electricity is set in the second case. Extremely electric shock caused Rong Fangmu to get on the second pole of the second face of the European Union, and the pair should show the appearance of waves ;;;- The wave layer electrode protects the capacitor and keeps the electricity. The cover and the cover are covered with a protective layer to protect one of the first electrodes, and the second electrode is connected to the device, and the electric hole is connected by the case and the diagram. The second figure is based on the use case, the electrode is conductive, the capacity is transparent, the second is exposed, and the naked body is connected to a large surface area of the meter. The wave surface, the second wave table, the first radiance, Page 18 577107 Page 19