Manufacturing method of display panel and etching solution

Abstract

The invention discloses a manufacturing method of a display panel and etching liquid. A first substrate is provided. A conductive layer stack is formed on the first substrate and includes a first sub-layer, a second sub-layer, and a third sub-layer. The first sub-layer includes molybdenum. The second sub-layer is disposed on the first sub-layer, the second sub-layer including a transparent conductive material, and the transparent conductive material including an indium-containing oxide. The third sub-layer is disposed between the first sub-layer and the second sub-layer, and the third sub-layer includes silver or a silver alloy. And performing an etching process in which the first sub-layer, the second sub-layer and the third sub-layer are etched by using an etching solution to form a first patterned sub-layer, a second patterned sub-layer and a third patterned sub-layer. The etchant includes 1 to 3 wt% of nitric acid, 30 to 50 wt% of acetic acid, 30 to 50 wt% of phosphoric acid, and the balance of water.

Description

Technical Field

[0001] The invention relates to a method for manufacturing a display panel and an etching liquid, and in particular to a method for manufacturing a display panel and an etching liquid for forming a high-quality reflective electrode. Background Art

[0002] Among different types of display panels, reflective display panels or transflective display panels have the advantage of low power consumption because they use ambient light as a light source to achieve display effects. Currently, many electronic products such as handwriting tablets, electronic papers, tablet PCs, and notebook computers use reflective or transflective display panels. However, how to improve the display quality of reflective or transflective display panels is one of the purposes of the present invention. Summary of the invention

[0003] The purpose of the present invention is to provide a method for manufacturing a display panel and an etching solution, and the technical problem to be solved is how to form a high-quality reflective electrode and improve the display quality of the display panel.

[0004] To solve the above technical problems, the present invention provides a method for manufacturing a display panel, which includes the following steps. A first substrate is provided. A conductive layer stack is formed on the first substrate, and the conductive layer stack includes a first sublayer, a second sublayer and a third sublayer, the material of the first sublayer includes molybdenum, the second sublayer is arranged on the first sublayer, the material of the second sublayer includes a transparent conductive material, and the transparent conductive material includes an indium-containing oxide, the third sublayer is arranged between the first sublayer and the second sublayer, and the material of the third sublayer includes silver or a silver alloy. A photoresist pattern is formed on the conductive layer stack. An etching process is performed on the conductive layer stack, and an etching solution is used in the etching process to etch the first sublayer, the second sublayer and the third sublayer to form a first patterned sublayer, a second patterned sublayer and a third patterned sublayer. The etching solution includes 1 to 3wt% nitric acid, 30 to 50wt% acetic acid, 30 to 50wt% phosphoric acid and the remaining content of water.

[0005] To solve the above technical problems, the present invention also provides an etching solution, which is used to perform an etching process on a conductive layer stack of a display panel to form a patterned conductive layer stack, and the etching solution includes 1 to 3wt% nitric acid, 30 to 50wt% acetic acid, 30 to 50wt% phosphoric acid and the remaining content of water. The conductive layer stack includes a first sublayer, a second sublayer and a third sublayer, and the third sublayer is arranged between the first sublayer and the second sublayer. The patterned conductive layer stack includes a first patterned sublayer, a second patterned sublayer and a third patterned sublayer, and the third patterned sublayer is arranged between the first patterned sublayer and the second patterned sublayer. In the etching process, the etching solution is used to etch the first sublayer, the second sublayer and the third sublayer to form the first patterned sublayer, the second patterned sublayer and the third patterned sublayer. The materials of the first sublayer and the first patterned sublayer respectively include molybdenum, the materials of the second sublayer and the second patterned sublayer respectively include a transparent conductive material, the transparent conductive material includes an indium oxide, and the materials of the third sublayer and the third patterned sublayer respectively include silver or a silver alloy.

[0006] In the manufacturing method of the display panel of the present invention, the etching liquid can be used to etch the conductive layer stack to form a reflective electrode, wherein the etching process is a single etching, and the etching process etches the first sublayer (including molybdenum), the second sublayer (including indium oxide) and the third sublayer (including silver or silver alloy) to form a patterned conductive layer stack. Through the etching process of the present invention and the first sublayer containing molybdenum is arranged under the third sublayer containing silver, the damage of the edge of the silver layer of the patterned conductive layer stack can be effectively suppressed, and the phenomenon of silver particles at the edge of the patterned conductive layer stack can also be effectively suppressed, all of which improve the reflection effect of the reflective electrode, thereby improving the display quality of the display panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 FIG. 1 is a schematic diagram of a step of forming a conductive layer stack in a method for manufacturing a display panel according to a first embodiment of the present invention.

[0008] Figure 2 It is a schematic diagram of the steps of forming a photoresist pattern and performing an etching process in the method for manufacturing a display panel according to the first embodiment of the present invention.

[0009] Figure 3 Schematic diagram of forming a reflective electrode by three etching steps.

[0010] Figure 4 It is a partially enlarged top view of a reflective electrode formed by three etching steps.

[0011] Figure 5 for Figure 4 Magnified view of area Q1 in FIG.

[0012] Figure 6 FIG. 1 is a schematic diagram of a step of forming a reflective electrode by one etching in a method for manufacturing a display panel according to a first embodiment of the present invention.

[0013] Figure 7 It is a partially enlarged top view of a reflective electrode formed by one etching in the manufacturing method of the display panel according to the first embodiment of the present invention.

[0014] Figure 8 for Figure 7 Magnified view of area Q2 in FIG.

[0015] Fig. 9 It is a schematic diagram of the step of forming a first alignment layer and remaining devices in the method for manufacturing a display panel according to the first embodiment of the present invention.

[0016] Fig.10 FIG. 4 is a flow chart of the steps of a method for manufacturing a display panel according to the first embodiment of the present invention.

[0017] Fig.11 and Fig.12 FIG. 1 is a schematic diagram of an example of forming a reflective electrode according to the first embodiment of the present invention.

[0018] Fig.13 FIG. 4 is a schematic diagram of a step of removing the second patterned sub-layer in a method for manufacturing a display panel according to a second embodiment of the present invention.

[0019] Fig.14 FIG. 4 is a cross-sectional schematic diagram of a display panel according to a second embodiment of the present invention.

[0020] Fig.15 FIG. 4 is a schematic diagram of a step of forming a photoresist pattern in a method for manufacturing a display panel according to a third embodiment of the present invention.

[0021] Fig.16 and Fig.17 FIG. 1 is a schematic diagram of an example of forming a reflective electrode according to the third embodiment of the present invention.

[0022] Description of reference numerals: 10-display panel; 100, 124-substrate; 1001-upper surface; 102-thin film transistor; 104, 132, 134, 138-insulating layer; 106, 136, 140-through hole; 108-conductive layer stack; 1100-first sublayer; 1102-third sublayer; 1104-second sublayer; 112-photoresist pattern; 114-etching process; 116-patterned conductive layer stack; 1180-first patterned sublayer; 1182-third sublayer Patterned sublayer; 1184-second patterned sublayer; 120-reflective electrode; 122-first alignment layer; 126-common electrode; 128-second alignment layer; 130-liquid crystal layer; AC-arrow; CD-distance; DE-drain; DR1, DR2-direction; GE-gate; GI-gate insulating layer; LT1-light; LT2-reflected light; PE-pixel electrode; Q1, Q1-region; RA-reflective region; S101-S107-steps; SE-source; SM-semiconductor layer. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to further understand the present invention, the preferred embodiments of the present invention are listed below, and the components and intended effects of the present invention are described in detail with the accompanying drawings. It should be noted that the drawings are simplified schematic diagrams, and therefore, only the components and combination relationships related to the present invention are shown to provide a clearer description of the basic architecture or implementation method of the present invention, while the actual components and layout may be more complex. In addition, for the convenience of explanation, the components shown in the various drawings of the present invention are not drawn in proportion to the actual number, shape, and size, and the detailed proportions can be adjusted according to the design requirements.

[0024] The following figures mark a direction DR1 and a direction DR2. Direction DR2 can be a normal direction or a top view direction, such as Figure 1 , the direction DR2 may be perpendicular to an upper surface 1001 of a substrate 100. The direction DR1 may be a horizontal direction and may be perpendicular to the direction DR2, such as Figure 1 , the direction DR1 may be parallel to the upper surface 1001 of the substrate 100. The following figures may describe the spatial relationship of the structures according to the direction DR1 and the direction DR2.

[0025] Please refer to Figures 1 to 10 , Figure 1 is a schematic diagram of a step of forming a conductive layer stack in a method for manufacturing a display panel according to a first embodiment of the present invention, Figure 2 FIG. 1 is a schematic diagram of steps of forming a photoresist pattern and performing an etching process in a method for manufacturing a display panel according to a first embodiment of the present invention, Figure 3 Schematic diagram of forming a reflective electrode by three etching steps. Figure 4This is a partially enlarged top view of the reflective electrode formed by three etching steps. Figure 5 for Figure 4 A magnified view of region Q1 in Figure 6 FIG. 1 is a schematic diagram of a step of forming a reflective electrode by one etching in a method for manufacturing a display panel according to a first embodiment of the present invention, Figure 7 FIG. 1 is a partially enlarged top view of a reflective electrode formed by one etching in the method for manufacturing a display panel according to the first embodiment of the present invention. Figure 8 for Figure 7 A magnified view of region Q2 in Fig. 9 is a schematic diagram of the steps of forming a first alignment layer and remaining devices in the method for manufacturing a display panel according to the first embodiment of the present invention, and Fig.10 FIG. 4 is a flow chart of the steps of a method for manufacturing a display panel according to the first embodiment of the present invention.

[0026] It should be understood that Fig.10 The steps shown in the embodiment may not be exhaustive, and other steps may be performed before, after, or between any of the steps shown. In addition, some steps may be performed simultaneously or in a sequential manner. Fig.10 The order shown in the figure is different from the order in which it is executed.

[0027] like Figure 1 and Fig.10 First, step S101 may be performed to provide a substrate 100, and a thin film transistor 102 and an insulating layer 104 are formed on the substrate 100, and the insulating layer 104 covers the thin film transistor 102. The substrate 100 may include a hard substrate such as a glass substrate, a plastic substrate, a quartz substrate or a sapphire substrate, but is not limited thereto. The substrate 100 may also include a flexible substrate such as a polyimide (PI) substrate or a polyethylene terephthalate (PET) substrate, but is not limited thereto. The insulating layer 104 may include an inorganic insulating material, an organic insulating material or a combination thereof, but is not limited thereto. The insulating layer 104 may include a single-layer structure or a multi-layer structure.

[0028] Next, a through hole 106 is formed in the insulating layer 104. Next, step S103 may be performed to form a conductive layer stack 108 on the substrate 100. Furthermore, the conductive layer stack 108 may be disposed on the insulating layer 104 and may fill the through hole 106 to be electrically connected to the thin film transistor 102. The conductive layer stack 108 includes a first sublayer 1100, a second sublayer 1104, and a third sublayer 1102. The second sublayer 1104 is disposed on the first sublayer 1100, and the third sublayer 1102 is disposed between the first sublayer 1100 and the second sublayer 1104.

[0029] In the present embodiment, the first sublayer 1100 may directly contact the third sublayer 1102 (i.e., the upper surface of the first sublayer 1100 directly contacts the lower surface of the third sublayer 1102), and the third sublayer 1102 may directly contact the second sublayer 1104 (i.e., the lower surface of the second sublayer 1104 directly contacts the upper surface of the third sublayer 1102), but the present invention is not limited thereto. The first sublayer 1100 may be a metal layer, the second sublayer 1104 may be a transparent conductive layer, and the third sublayer 1102 may be a metal layer. The method of forming the conductive layer stack 108 may include sequentially forming the first sublayer 1100, the third sublayer 1102, and the second sublayer 1104 on the insulating layer 104. The conductive layer stack 108 may be electrically connected to the thin film transistor 102 through the through hole 106.

[0030] The material of the first sublayer 1100 may include a metal, such as molybdenum, but is not limited thereto. The material of the second sublayer 1104 may include a transparent conductive material, and the transparent conductive material includes an indium-containing oxide. For example, the indium-containing oxide may include indium tin oxide (ITO) or indium zinc oxide (IZO), but is not limited thereto. The material of the third sublayer 1102 may include a metal, such as silver or a silver alloy, but is not limited thereto. Therefore, the materials of the first sublayer 1100, the third sublayer 1102, and the second sublayer 1104 may be different from each other.

[0031] Since the third sub-layer 1102 is silver or silver alloy, the adhesion between the third sub-layer 1102 and the insulating layer 104 is poor and is easy to peel off. Therefore, in this embodiment, the first sub-layer 1100 is also arranged between the third sub-layer 1102 and the insulating layer 104. The first sub-layer 1100 can be molybdenum, and the first sub-layer 1100 directly contacts the insulating layer 104 (that is, the lower surface of the first sub-layer 1100 directly contacts the insulating layer 104), which can alleviate the peeling phenomenon of the third sub-layer 1102.

[0032] In addition, since the material of the third sub-layer 1102 may include metal, if the conductive layer stack 108 does not include a film layer (such as the second sub-layer 1104) covering the third sub-layer 1102, the surface of the third sub-layer 1102 may react with foreign substances during the period of waiting for the subsequent process (such as the period after the conductive layer stack 108 is formed and before the patterning process of the conductive layer stack 108 is performed) and / or during the subsequent process (such as the patterning process of the conductive layer stack 108). Taking the embodiment in which the material of the third sub-layer 1102 includes silver or a silver alloy as an example, silver can easily react chemically with foreign substances to cause discoloration and / or a decrease in reflectivity. Therefore, in the process of forming the conductive layer stack 108, after the third sub-layer 1102 is formed, forming the second sub-layer 1104 including a transparent conductive material on the third sub-layer 1102 can protect the third sub-layer 1102 and prevent the third sub-layer 1102 from reacting with foreign substances during the period of waiting for the subsequent process and / or during the period of performing the subsequent process.

[0033] like Figure 2 , then step S105 may be performed to form a photoresist pattern 112 on the conductive layer stack 108. The photoresist pattern 112 covers a portion of the conductive layer stack 108 and overlaps the through hole 106. Then, step S107 may be performed to perform an etching process 114 on the conductive layer stack 108 through the photoresist pattern 112, and in the etching process 114, an etching solution is used to etch the first sub-layer 1100, the second sub-layer 1104, and the third sub-layer 1102 to form a patterned conductive layer stack 116 (shown in FIG. Figure 3 and Figure 6 ).

[0034] Next, the present invention is described using two different etching processes 114 (such as Figures 3 to 5 The three-step etching process is similar to Figures 6 to 8 A comparative result of forming the patterned conductive layer stack 116 by a one-step etching process.

[0035] like Figure 3 , and by Figure 3 From top to bottom, in the first etching process, the first sub-layer 1100, the second sub-layer 1104, and the third sub-layer 1102 can be etched respectively through three etching steps. Figure 3 In the top figure, the second sub-layer 1104 may be etched to form a second patterned sub-layer 1184. Figure 3 In the middle figure, the third sub-layer 1102 is etched to form a third patterned sub-layer 1182. Figure 3 As shown in the bottom figure, the first sub-layer 1100 is then etched to form a first patterned sub-layer 1180. Figure 3The patterned conductive layer stack 116 may include a first patterned sub-layer 1180, a second patterned sub-layer 1184, and a third patterned sub-layer 1182. In the present embodiment, the patterned conductive layer stack 116 is located in the reflective region RA of the display panel and serves as the reflective electrode 120, but the present invention is not limited thereto.

[0036] like Figure 4 , Figure 4 Is completed Figure 3 FIG. 1 is a partial enlarged top view of the reflective electrode 120 formed after the etching process. Figure 5 for Figure 4 The reflective electrodes 120 of the two pixels (or two sub-pixels) are respectively located at Figure 4 The left and right of Figure 4 and Figure 5 In FIG. 1 , the first patterned sub-layer 1180 is blocked by the third patterned sub-layer 1182 and therefore does not appear in FIG. Figure 4 and Figure 5 In some embodiments, the first patterned sublayer 1180, the third patterned sublayer 1182, and the second patterned sublayer 1184 of the reflective electrode 120 include indium tin oxide, silver, and indium tin oxide, respectively. In some embodiments, the first patterned sublayer 1180, the third patterned sublayer 1182, and the second patterned sublayer 1184 of the reflective electrode 120 include molybdenum, silver, and indium tin oxide, respectively.

[0037] After the etching process 114 etches the first sub-layer 1100, the second sub-layer 1104, and the third sub-layer 1102 through three etching steps to form the patterned conductive layer stack 116, some locations near the edge of the third patterned sub-layer 1182 (i.e., the silver layer) are damaged (e.g., Figure 5 ), or silver particles may be formed near the edge of the third patterned sub-layer 1182 (eg, Figure 5 The silver particles may diffuse to the outside of the third patterned sub-layer 1182 (eg, Figure 5 These may reduce the reflective effect of the reflective electrode 120, or generate gray spots in the display image, or cause a decrease in product yield.

[0038] In order to solve the shortcomings of the first etching process described above, the inventors conducted experiments with etching solutions of various composition ratios and obtained an etching solution suitable for etching the first sublayer 1100, the second sublayer 1104, and the third sublayer 1102. By etching the first sublayer 1100, the second sublayer 1104, and the third sublayer 1102 with the above etching solution and using molybdenum as the material of the first sublayer 1100, the resulting reflective electrode 120 does not have the problem of silver layer edge damage and silver particles caused by the first etching process described above (i.e., etching indium tin oxide, silver and indium tin oxide or molybdenum, silver and indium tin oxide in three etching steps). Next, the etching solution and etching method used in the second etching process (such as Figures 6 to 8 ).

[0039] In the second etching process, as Figure 2 and Figure 6 The present invention provides an etching solution, which can be used to etch the first sublayer 1100, the second sublayer 1104 and the third sublayer 1102 of the conductive layer stack 108 to form a first patterned sublayer 1180, a second patterned sublayer 1184 and a third patterned sublayer 1182, wherein the first patterned sublayer 1180 includes molybdenum, the second patterned sublayer 1184 includes an indium-containing oxide (such as indium tin oxide or indium zinc oxide), and the third patterned sublayer 1182 includes silver or a silver alloy. Wherein, based on the total weight of the etching solution, the etching solution includes 1 to 3wt% nitric acid, 30 to 50wt% acetic acid, 30 to 50wt% phosphoric acid and the remaining content of water. That is, the etching solution of the present invention only contains nitric acid, acetic acid, phosphoric acid and water, without adding other components, that is, the etching solution of the present invention is composed of nitric acid, acetic acid, phosphoric acid and water.

[0040] The water used in the etching solution may be deionized water. In addition, the temperature of the etching solution used in the etching process 114 is greater than or equal to 26 degrees Celsius and less than or equal to 35 degrees Celsius. Figure 2 In the etching process 114, the etching solution is used to etch the first sub-layer 1100, the second sub-layer 1104 and the third sub-layer 1102 to form Figure 6 The first patterned sub-layer 1180, the second patterned sub-layer 1184 and the third patterned sub-layer 1182 are formed in the etching process 114, so the etching process 114 is a one-time etching.

[0041] In this embodiment, the etching process 114 may be performed by, for example, applying the above-mentioned etching solution to the Figure 2On the conductive layer stack 108 and the photoresist pattern 112, a portion of the conductive layer stack 108 is not covered by the photoresist pattern 112 and is removed by the etching solution, while another portion of the conductive layer stack 108 is covered by the photoresist pattern 112 and remains unremoved to form a patterned conductive layer stack 116. However, the etching method of the etching process 114 of the present invention is not limited thereto.

[0042] The etching solution of the present invention particularly increases the proportion of acetic acid in the etching solution to the same proportion as that of phosphoric acid in the etching solution, that is, the proportions of acetic acid and phosphoric acid in the etching solution are both in the range of 30 to 50 wt %, and the proportion of nitric acid in the etching solution is reduced to 1 to 3 wt %, thereby improving the etching uniformity so that the flatness of the edge of the reflective electrode 120 formed after etching is improved, thereby improving the display quality of the display panel, but the present invention is not limited thereto.

[0043] In addition, the etching solution of the present invention is composed of nitric acid, acetic acid, phosphoric acid and water, and no other components need to be added, so the preparation of the etching solution can be simplified, and during the production process, only the content of nitric acid, acetic acid and phosphoric acid in the etching solution needs to be monitored to see if it meets the standards, thereby reducing the production monitoring cost.

[0044] like Figure 7 and Figure 8 , Figure 7 is a partially enlarged top view of the reflective electrode 120 after one-time etching using the etching solution of the present invention, and Figure 8 for Figure 7 The first patterned sublayer 1180, the third patterned sublayer 1182 and the second patterned sublayer 1184 of the reflective electrode 120 include molybdenum, silver and indium tin oxide respectively. Figure 7 and Figure 8 In FIG. 1 , the first patterned sub-layer 1180 is blocked by the third patterned sub-layer 1182 and therefore does not appear in FIG. Figure 7 and Figure 8 middle.

[0045] from Figure 7 and Figure 8 Obviously, when the etching process 114 uses the etching solution of the present invention to etch the first sub-layer 1100, the second sub-layer 1104 and the third sub-layer 1102 at one time to form the reflective electrode 120, the edge of the reflective electrode 120 may not have the phenomenon of silver layer damage and silver particles, so that the reflective effect of the reflective electrode 120 is improved, thereby improving the display quality and yield of the display panel.

[0046] The following is a description of the data obtained by the inventor through experiments. First, the second etching process described above is performed with etching solutions of different temperatures within a fixed time (e.g., 1 minute). In one experiment, the temperature of the etching solution is 26 degrees Celsius, and after etching, a distance CD (e.g., Figure 7 ) may be approximately 5.85 microns, and the difference in distance between two adjacent third patterned sub-layers 1182 before and after etching may be approximately 3.85 microns.

[0047] In one experiment, the temperature of the etching solution is 30 degrees Celsius, and the distance CD between two adjacent third patterned sub-layers 1182 after etching can be about 6.12 microns, and the difference between the distances between two adjacent third patterned sub-layers 1182 before and after etching can be about 4.12 microns. In one experiment, the temperature of the etching solution is 35 degrees Celsius, and the distance CD between two adjacent third patterned sub-layers 1182 after etching can be about 8.24 microns, and the difference between the distances between two adjacent third patterned sub-layers 1182 before and after etching can be about 6.24 microns.

[0048] Furthermore, the second etching process is performed at a fixed temperature (e.g., 30 degrees Celsius) of the etching solution and at different times. In one experiment, the time is 35 seconds, and the distance CD between two adjacent third patterned sub-layers 1182 after etching can be about 5.85 microns, and the difference between the distances between two adjacent third patterned sub-layers 1182 before and after etching can be about 3.35 microns. In another experiment, the time is 39 seconds, and the distance CD between two adjacent third patterned sub-layers 1182 after etching can be about 6.12 microns, and the difference between the distances between two adjacent third patterned sub-layers 1182 before and after etching can be about 3.62 microns.

[0049] In one experiment, the time is 43 seconds, and the distance CD between two adjacent third patterned sub-layers 1182 after etching can be about 7.47 microns, and the difference between the distances between two adjacent third patterned sub-layers 1182 before and after etching can be about 3.97 microns. In one experiment, the time is 63 seconds, and the distance CD between two adjacent third patterned sub-layers 1182 after etching can be about 9.19 microns, and the difference between the distances between two adjacent third patterned sub-layers 1182 before and after etching can be about 5.19 microns.

[0050] In summary, the present invention adopts the second etching process described above as the etching process 114 in step S107 of the method for manufacturing a display panel of the first embodiment of the present invention. That is, the present invention provides an etching solution, wherein the etching solution includes 1 to 3 wt% nitric acid, 30 to 50 wt% acetic acid, 30 to 50 wt% phosphoric acid and the remaining content of water. In the etching process 114, the first sublayer 1100, the second sublayer 1104 and the third sublayer 1102 are etched together using the above-mentioned etching solution to form a first patterned sublayer 1180, a second patterned sublayer 1184 and a third patterned sublayer 1182, wherein the first patterned sublayer 1180 includes molybdenum, the second patterned sublayer 1184 includes an indium-containing oxide (such as indium tin oxide or indium zinc oxide), and the third patterned sublayer 1182 includes silver or a silver alloy, so the etching process 114 in step S107 of the method for manufacturing a display panel of the first embodiment of the present invention is a one-time etching process.

[0051] In addition, the temperature of the etching solution used in the etching process 114 may be greater than or equal to 26 degrees Celsius and less than or equal to 35 degrees Celsius, the etching time may be greater than or equal to 35 seconds and less than or equal to 63 seconds, and the distance CD between two adjacent third patterned sub-layers 1182 after etching may be greater than or equal to 5.85 microns and less than or equal to 9.19 microns, and the difference in the distance between two adjacent third patterned sub-layers 1182 before and after etching may be greater than or equal to 3.35 microns and less than or equal to 6.24 microns, but is not limited to this.

[0052] Another example Fig.11 and Fig.12 ,in Fig.11 Corresponds to Figure 2 ,and Fig.12 Corresponds to Figure 6 .exist Fig.11 and Fig.12 In Figure 2 and Figure 6 The thin film transistor 102 in the embodiment is a bottom gate thin film transistor for example, but is not limited thereto. In other embodiments, Figure 2 and Figure 6 The thin film transistor 102 in the embodiment may be a top gate thin film transistor. Fig.11 , the thin film transistor 102 includes a gate electrode GE, a semiconductor layer SM, a source electrode SE and a drain electrode DE. The gate electrode GE is disposed on the substrate 100, the semiconductor layer SM is disposed on the gate electrode GE, and a gate insulating layer GI is disposed between the gate electrode GE and the semiconductor layer SM. The source electrode SE and the drain electrode DE are disposed on the gate insulating layer GI and are located on both sides of the semiconductor layer SM.

[0053] The gate electrode GE, the source electrode SE and the drain electrode DE include conductive materials, such as metal, but not limited thereto. The semiconductor layer SM includes semiconductor materials, such as amorphous silicon, polysilicon or metal oxide, but not limited thereto.

[0054] The insulating layer 104 may include a multilayer structure, for example, the insulating layer 104 may include an insulating layer 132 and an insulating layer 134, but is not limited thereto. The insulating layer 132 is disposed on the source electrode SE and the drain electrode DE, and the insulating layer 134 is disposed on the insulating layer 132. The gate insulating layer GI, the insulating layer 132, and the insulating layer 134 may include an inorganic insulating material, an organic insulating material, or a combination thereof, but is not limited thereto. For example, the insulating layer 132 may include an inorganic insulating material, and the insulating layer 134 may include an organic insulating material and serve as a planar layer, but is not limited thereto. The thickness of the insulating layer 134 may be greater than the thickness of the gate insulating layer GI and the thickness of the insulating layer 132, but is not limited thereto.

[0055] The through hole 106 may pass through the insulating layer 134 and the insulating layer 132 and expose a portion of the surface of the drain electrode DE. The conductive layer stack 108 may be filled in the through hole 106 and electrically connected to the drain electrode DE. For example, the first sublayer 1100 in the conductive layer stack 108 may contact the drain electrode DE. Then, an etching process 114 is performed to obtain a Fig.12 The reflective electrode 120 in the embodiment of the present invention.

[0056] Then, if Fig. 9 , a first alignment layer 122 is formed on the reflective electrode 120 , the first alignment layer 122 may cover the reflective electrode 120 and the insulating layer 104 , and the first alignment layer 122 is in direct contact with the second patterned sub-layer 1184 .

[0057] Next, a substrate 124 is provided, and a common electrode 126 and a second alignment layer 128 are formed on the substrate 124, and the common electrode 126 is disposed between the substrate 124 and the second alignment layer 128. The substrate 124 may include a hard or flexible transparent substrate, but is not limited thereto. The common electrode 126 may include a transparent conductive material, but is not limited thereto.

[0058] Next, the substrate 100 and the substrate 124 are assembled, and a liquid crystal layer 130 is disposed between the substrate 100 and the substrate 124 to form the display panel 10. In particular, Figures 1 to 9 and Figure 11 to Figure 12 The cross-sectional view of a pixel or a sub-pixel of the display panel 10 is used as an example. Each pixel or each sub-pixel of the display panel 10 has a reflective region RA, and the reflective electrode 120 is located in the reflective region RA for reflecting light. The liquid crystal layer 130 may be disposed between the first alignment layer 122 and the second alignment layer 128.

[0059] like Fig. 9, a light LT1 of an ambient light or front light module can enter the display panel 10 from the substrate 124, and be reflected by the reflective electrode 120 to form a reflected light LT2, and the reflected light LT2 can be emitted from the display panel 10 through the liquid crystal layer 130 and the substrate 124 to reach the user's eyes. In this embodiment, the display panel 10 can be a reflective type display panel or a transflective type display panel, but is not limited thereto.

[0060] Therefore, if Fig. 9 A display panel 10 of the present embodiment includes a substrate 100, a substrate 124, a liquid crystal layer 130, a thin film transistor 102, a reflective electrode 120, a first alignment layer 122, and a second alignment layer 128. The substrate 124 and the substrate 100 are arranged opposite to each other in the direction DR2, the liquid crystal layer 130 is arranged between the substrate 100 and the substrate 124, the thin film transistor 102 is arranged between the substrate 100 and the liquid crystal layer 130, the reflective electrode 120 is arranged between the thin film transistor 102 and the liquid crystal layer 130, the reflective electrode 120 is electrically connected to the thin film transistor 102, and the reflective electrode 120 includes a transparent conductive layer (i.e., a first patterned sub-layer 1180), a metal layer (i.e., a third patterned sub-layer 1182), and another transparent conductive layer (i.e., a second patterned sub-layer 1184). The metal layer is arranged between the two transparent conductive layers, the transparent conductive layer includes indium oxide, and the metal layer includes silver or a silver alloy.

[0061] The display panel 10 further includes an insulating layer 104 disposed on the substrate 100 and the thin film transistor 102, and the insulating layer 104 is disposed between the reflective electrode 120 and the substrate 100. The insulating layer 104 includes a through hole 106, and the reflective electrode 120 is filled in the through hole 106 and electrically connected to the thin film transistor 102.

[0062] The first alignment layer 122 is disposed between the liquid crystal layer 130 and the reflective electrode 120. The second alignment layer 128 is disposed between the substrate 124 and the liquid crystal layer 130. The display panel 10 further includes a common electrode 126 disposed between the substrate 124 and the second alignment layer 128.

[0063] The etching solution and the method for manufacturing the display panel of the present invention are not limited to the above-mentioned embodiments. Other embodiments of the present invention will be further disclosed below. However, in order to simplify the description and highlight the differences between the embodiments, the same reference numerals are used below to mark the same components, and the repeated parts will not be repeated.

[0064] Please refer to Fig.13 and Fig.14 , Fig.13 is a schematic diagram of a step of removing the second patterned sub-layer in a method for manufacturing a display panel according to a second embodiment of the present invention, and Fig.14 FIG. 2 is a cross-sectional view of a display panel according to a second embodiment of the present invention. The difference from the first embodiment is that the second embodiment is Figure 2 The etching process 114 is used to form Figure 6 After the patterned conductive layer stack 116 is formed and the photoresist pattern 112 is removed, the second patterned sublayer 1184 of the patterned conductive layer stack 116 may be removed to form a reflective electrode 120. The reflective electrode 120 of the present embodiment includes the first patterned sublayer 1180 and the third patterned sublayer 1182, but does not include the second patterned sublayer 1184. In some embodiments, the method of removing the second patterned sublayer 1184 may include removing the second patterned sublayer 1184 using an etching solution including oxalic acid, but is not limited thereto.

[0065] Thus, the third patterned sub-layer 1182 in the reflective electrode 120 can be exposed and not covered by the second patterned sub-layer 1184. Fig.14 The first alignment layer 122 is formed on the third patterned sub-layer 1182 within a specific time after the second patterned sub-layer 1184 is removed, so as to prevent the exposed surface of the third patterned sub-layer 1182 from reacting with external substances and causing a decrease in reflectivity and an increase in the value of b* in the CIE L*a*b* color model. Therefore, in this embodiment, the first alignment layer 122 covers the third patterned sub-layer 1182 and is in direct contact with the third patterned sub-layer 1182.

[0066] In the present embodiment, the patterning process can be performed in the presence of the second sub-layer 1104 (i.e., the conductive layer stack 108 including the first sub-layer 1100, the second sub-layer 1104, and the third sub-layer 1102 is patterned), and the second patterned sub-layer 1184 is removed after the patterning process to increase the reflectivity of the reflective electrode 120 and reduce the value of b* in the CIE L*a*b* color model. In this way, the third sub-layer 1102 and the silver in the third patterned sub-layer 1182 can be protected from reacting with foreign substances before the second patterned sub-layer 1184 is removed, and the reflective electrode 120 of the display panel 10 can have a better reflectivity and a lower b* value (which can reduce the yellowing phenomenon of the picture), thereby improving the picture quality of the display panel 10.

[0067] In the present embodiment, the time from removing the second patterned sub-layer 1184 to forming the first alignment layer 122 on the third patterned sub-layer 1182 is less than or equal to 21 hours, and preferably less than or equal to 12 hours. Because the exposed surface of the third patterned sub-layer 1182 is easy to react with external substances, as the third patterned sub-layer 1182 is exposed for a longer time, the reflectivity of the reflective electrode 120 will be lower, and the value of b* of the reflective electrode 120 will be higher (the picture will be yellowish). Therefore, the next process step (such as setting the first alignment layer 122) needs to be performed within a specific time after removing the second patterned sub-layer 1184, wherein the above-mentioned specific time is less than or equal to 21 hours, and preferably less than or equal to 12 hours.

[0068] In the present embodiment, the process of removing the second patterned sub-layer 1184 to form the reflective electrode 120 may not require the use of a mask, thereby reducing the process cost, but the present invention is not limited thereto. For example, after performing the patterning process of step S107 and removing the photoresist pattern 112, the second patterned sub-layer 1184 may be removed (for example, the second patterned sub-layer 1184 may be removed using an etching solution including oxalic acid).

[0069] In some other embodiments, a photomask may be used in the process of removing the second patterned sub-layer 1184 to form the reflective electrode 120, but the present invention is not limited thereto. For example, after performing the patterning process of step S107 and removing the photoresist pattern 112, a photomask is then used to form a photoresist pattern, and the photoresist pattern has an opening corresponding to the reflective area RA, and then the second patterned sub-layer 1184 located in the reflective area RA is removed (for example, the second patterned sub-layer 1184 located in the reflective area RA is removed using an etching solution including oxalic acid).

[0070] In this embodiment, the steps after forming the first alignment layer 122 may be the same as those in the first embodiment, and will not be described again.

[0071] Please refer to Figures 15 to 17 , Fig.15 is a schematic diagram of a step of forming a photoresist pattern in a method for manufacturing a display panel according to a third embodiment of the present invention, and Fig.16 and Fig.17 FIG. 1 is a schematic diagram of an example of forming a reflective electrode according to the third embodiment of the present invention.

[0072] like Fig.15 , which is different from the first embodiment in that after the insulating layer 104 is formed, a through hole 136 is formed in the insulating layer 104. Next, a pixel electrode PE is formed on the insulating layer 104, and the pixel electrode PE fills the through hole 136 and is electrically connected to the thin film transistor 102. The pixel electrode PE includes a transparent conductive material, such as indium tin oxide or indium zinc oxide, but is not limited thereto.

[0073] Next, an insulating layer 138 is formed on the insulating layer 104 and the pixel electrode PE, and the insulating layer 138 covers the pixel electrode PE. The insulating layer 138 may include an inorganic insulating material, an organic insulating material, or a combination thereof, but is not limited thereto. In addition, a through hole 140 is formed in the insulating layer 138.

[0074] Next, a conductive layer stack 108 is formed on the insulating layer 138, and the conductive layer stack 108 fills the through hole 140 and is electrically connected to the pixel electrode PE. The formation of the photoresist pattern 112 and subsequent steps may refer to the first embodiment or the second embodiment, and will not be repeated here.

[0075] Another example Fig.16 ,exist Fig.16 In Fig.15 The thin film transistor 102 in the figure is a bottom-gate thin film transistor for example, but is not limited thereto. In other embodiments, Fig.15 The thin film transistor 102 in the embodiment may be a top gate thin film transistor. Fig.16 In this example, the insulating layer 104 includes a through hole 136, which may penetrate the insulating layer 104 and expose a portion of the surface of the drain electrode DE, and the pixel electrode PE may be filled in the through hole 136 and electrically connected to the drain electrode DE. For example, the pixel electrode PE may contact the drain electrode DE.

[0076] The insulating layer 138 includes a through hole 140. The through hole 140 can penetrate the insulating layer 138 and expose a portion of the surface of the pixel electrode PE. The conductive layer stack 108 can be filled in the through hole 140 and electrically connected to the pixel electrode PE. For example, the first sublayer 1100 in the conductive layer stack 108 can contact the pixel electrode PE. Then, an etching process 114 is performed to obtain the following. Fig.17 The reflective electrode 120 in the embodiment of the present invention.

[0077] In the first to third embodiments described above, the reflective electrode 120 is located in the reflective area of ​​the reflective or semi-transmissive semi-reflective display panel, and the reflective electrode 120 is used to reflect ambient light or light from the front light module, but the invention is not limited thereto. In other embodiments, the reflective electrode may be located in an organic light emitting diode display panel and used to reflect light generated by the light emitting layer of the organic light emitting diode. Therefore, the above-mentioned manufacturing method for forming the reflective electrode 120 and the etching solution for forming the reflective electrode 120 may also be applied to forming the reflective electrode of the organic light emitting diode display panel, and will not be described in detail here.

[0078] In summary, in the etching solution of the present invention, based on the total weight of the etching solution, the etching solution includes 1 to 3wt% nitric acid, 30 to 50wt% acetic acid, 30 to 50wt% phosphoric acid and the remaining content of water. In the method for making a display panel of the present invention, the etching solution can be used to etch a conductive layer stack to form a patterned conductive layer stack, wherein the etching process is a single etching, and the first sublayer (including molybdenum), the second sublayer (including indium oxide) and the third sublayer (including silver or silver alloy) of the conductive layer stack are etched together to form the first patterned sublayer, the second patterned sublayer and the third patterned sublayer of the patterned conductive layer stack. Through the etching process of the present invention and the first sublayer containing molybdenum is set under the third sublayer containing silver, the damage of the edge of the silver layer of the patterned conductive layer stack can be effectively suppressed, and the phenomenon of silver particles at the edge of the patterned conductive layer stack can also be effectively suppressed. The reflective electrode includes at least the first patterned sublayer and the third patterned sublayer of the patterned conductive layer stack. By using the above-mentioned etching solution and etching process, the reflection effect of the reflective electrode is improved, thereby improving the display quality of the display panel. In some embodiments, the second patterned sublayer may be further removed. In this way, the reflectivity of the reflective electrode may be increased. In addition, the value of b* in the CIE L*a*b* color model may be reduced, thereby reducing the yellowing phenomenon. This may further improve the image quality of the display panel.

[0079] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for manufacturing a display panel, characterized in that: include: Providing a first substrate; A conductive layer stack is formed on the first substrate, and the conductive layer stack includes: a first sub-layer, wherein the material of the first sub-layer comprises molybdenum; a second sublayer, disposed on the first sublayer, wherein the material of the second sublayer comprises a transparent conductive material, and the transparent conductive material comprises an indium-containing oxide; and a third sublayer, disposed between the first sublayer and the second sublayer, wherein the material of the third sublayer comprises silver or a silver alloy; forming a photoresist pattern on the conductive layer stack; and An etching process is performed on the conductive layer stack, in which an etching solution is used to etch the first sublayer, the second sublayer and the third sublayer to form a first patterned sublayer, a second patterned sublayer and a third patterned sublayer, The etching solution comprises 1 to 3 wt % of nitric acid, 30 to 50 wt % of acetic acid, 30 to 50 wt % of phosphoric acid and the remainder is water.

2. The method for manufacturing a display panel according to claim 1, wherein: The temperature of the etching solution is greater than or equal to 26 degrees Celsius and less than or equal to 35 degrees Celsius.

3. The method for manufacturing a display panel according to claim 1, wherein: The display panel has a reflective area, and the first patterned sub-layer, the second patterned sub-layer and the third patterned sub-layer are located in the reflective area of ​​the display panel.

4. The method for manufacturing a display panel according to claim 1, wherein: The method further includes removing the photoresist pattern after performing the etching process, and removing the second patterned sub-layer after removing the photoresist pattern.

5. The method for manufacturing a display panel according to claim 4, wherein: The method further includes forming a first alignment layer on the third patterned sub-layer within a specific time after removing the second patterned sub-layer, and the first alignment layer is in direct contact with the third patterned sub-layer.

6. The method for manufacturing a display panel according to claim 5, wherein: The specific time is less than or equal to twenty-one hours.

7. The method for manufacturing a display panel according to claim 1, wherein: The indium-containing oxide includes indium tin oxide or indium zinc oxide.

8. The method for manufacturing a display panel according to claim 1, wherein: The etching process is one-time etching.

9. An etching solution, characterized in that: The etching liquid is used to perform an etching process on a conductive layer stack of a display panel to form a patterned conductive layer stack, and the etching liquid includes: 1 to 3 wt % nitric acid; 30 to 50 wt % acetic acid; 30 to 50 wt % phosphoric acid; and The remaining water content, The conductive layer stack includes a first sublayer, a second sublayer and a third sublayer, and the third sublayer is arranged between the first sublayer and the second sublayer. The patterned conductive layer stack includes a first patterned sublayer, a second patterned sublayer and a third patterned sublayer, and the third patterned sublayer is arranged between the first patterned sublayer and the second patterned sublayer. In the etching process, the first sublayer, the second sublayer and the third sublayer are etched using the etching solution to form the first patterned sublayer, the second patterned sublayer and the third patterned sublayer. The materials of the first sublayer and the first patterned sublayer include molybdenum, the materials of the second sublayer and the second patterned sublayer include a transparent conductive material, and the transparent conductive material includes indium oxide. The materials of the third sublayer and the third patterned sublayer include silver or a silver alloy.

10. The etching solution according to claim 9, characterized in that The etching process is one-time etching.

11. The etching solution according to claim 9, characterized in that The temperature of the etching solution is greater than or equal to 26 degrees Celsius and less than or equal to 35 degrees Celsius.

12. The etching solution according to claim 9, characterized in that The indium-containing oxide includes indium tin oxide or indium zinc oxide.

13. The etching solution according to claim 9, characterized in that The display panel has a reflective area, and the patterned conductive layer stack is located in the reflective area of ​​the display panel.

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