[0052] Figure 2A~Figure 2G It is a schematic diagram of a manufacturing method of a pixel structure of the present invention. Please refer to Figure 2A First, a substrate 200 is provided. The material of the substrate 200 is, for example, a hard or soft material such as glass and plastic. Next, a first conductive layer 210 is formed on the substrate 200, where the first conductive layer 210 is formed, for example, by sputtering, evaporation or other thin film deposition techniques.
[0053] Then, like Figure 2B As shown, a first mask S1 is provided above the first conductive layer 210, and a part of the first conductive layer 210 is exposed by the first mask S1, and a laser L is used to irradiate the first conductive layer 210 through the first mask S1. In detail, the first conductive layer 210 irradiated by the laser light L will absorb the energy of the laser light L and be ablated from the surface of the substrate 200. Specifically, the energy of the laser L used to peel off the first conductive layer 210 is, for example, 10 mJ/cm 2 Up to 500mJ/cm 2 between. In addition, the wavelength of the laser light L is, for example, between 100 nm and 400 nm.
[0054] After that, like Figure 2C As shown, after removing a portion of the first conductive layer 210 exposed by the first mask S1, the remaining first conductive layer 210 constitutes the gate 212. It is worth noting that, unlike the conventional use of an expensive photomask to fabricate the gate 212, the present invention uses a low-cost mask S1 to complete the fabrication of the gate 212, thus saving costs.
[0055] Next, please refer to Figure 2D A gate insulating layer 220 covering the gate 212 is formed on the substrate 200, wherein the gate insulating layer 220 is formed by, for example, chemical vapor deposition (CVD) or other suitable thin film deposition techniques, and the gate The material of the insulating layer 220 is, for example, a dielectric material such as silicon oxide, silicon nitride, or silicon oxynitride. Next, a semiconductor layer 230 and a second conductive layer 240 are sequentially formed on the gate insulating layer 220. In this embodiment, the material of the semiconductor layer 230 is, for example, amorphous silicon or other semiconductor materials, and the material of the second conductive layer 240 is, for example, aluminum (Al), molybdenum (Mo), titanium (Ti), and neodymium. (Nd), the aforementioned nitrides such as molybdenum nitride (MoN), titanium nitride (TiN), their laminates, the aforementioned alloys or other conductive materials.
[0056] Please refer to Figure 2E After the second conductive layer 240 is formed, a photoresist layer 250 is formed on the second conductive layer 240 above the gate 212. Such as Figure 2E As shown, the photoresist layer 250 can be divided into a first photoresist block 250a and a second photoresist block 250b located on both sides of the first photoresist block 250a, and The thickness of the first photoresist block 250a is smaller than the thickness of the second photoresist block 250b. Next, a first etching process is performed on the second conductive layer 240 and the semiconductor layer 230 using the photoresist layer 250 as a mask.
[0057] Next, reduce the thickness of the photoresist layer 250 until the first photoresist block 250a is completely removed, such as Figure 2F As shown, the method of reducing the thickness of the photoresist layer 250 is, for example, ashing. Please continue to refer Figure 2F After the first photoresist block 250a is completely removed, a second etching process is performed on the second conductive layer 240 using the remaining second photoresist block 250b as a mask. In this embodiment, the first etching process and the second etching process are, for example, wet etching. In other embodiments, the etching process may also be dry etching.
[0058] After that, please refer to Figure 2G After the process of removing the remaining photoresist layer 250 is performed, the remaining second conductive layer 240 constitutes the source electrode 242 and the drain electrode 244, and the remaining semiconductor layer 230 constitutes the channel layer 232, wherein the source electrode 242 and The drain 244 is disposed in a partial region of the channel layer 232, and the gate 212, the channel layer 232, the source 242, and the drain 244 constitute a thin film transistor 260. In this embodiment, the process of removing the photoresist layer 250 is, for example, a wet etching process.
[0059] It is worth noting that, unlike the known ones, the channel layer 232, the source electrode 242 and the drain electrode 244 of the present invention are formed at the same time, which can reduce a photomask process and reduce the complexity of the process. In addition, the channel layer 232, the source electrode 242, and the drain electrode 244 of the above-mentioned thin film transistor 260 are formed, for example, through the same half-tone mask or gray-tone mask process. . In addition, in other embodiments, the second conductive layer 240 and the photoresist layer 250 (shown in Figure 2D ) Before, an ohmic contact layer (not shown) may be formed on the surface of the semiconductor layer 230, and then a part of the ohmic contact layer (not shown) may be removed by the first etching process and the second etching process. For example, ion doping can be used to form an N-type doped region on the surface of the semiconductor layer 230 to reduce the contact resistance between the semiconductor layer 230 and the second conductive layer 240.
[0060] Then please refer to Figure 2H , A patterned protection layer 272 is formed on the thin film transistor 260, wherein the patterned protection layer 272 exposes a part of the drain electrode 244, such as Figure 2H As shown, the patterned protective layer 272 has, for example, a contact opening H exposing the drain electrode 244. In this embodiment, the method of forming the patterned protective layer 272 is, for example, after the thin film transistor 260 is formed, the protective layer 270 (shown in Figure 3A ) On the thin film transistor 260 and the gate insulating layer 220. Then, the protective layer 270 is patterned, and the method of patterning the protective layer 270 is, for example, a photolithography etching process.
[0061] Next, please refer to Figure 2I , A pixel electrode 282 is formed on the patterned protective layer 272. In this embodiment, the pixel electrode 282 is connected to the drain electrode 244 through the contact opening H. In this embodiment, the method of forming the pixel electrode 282 is, for example, after the patterned protective layer 272 is formed, and then an electrode material layer 280 is formed on the protective layer 270 and the drain electrode 244. Then, pattern the electrode material layer 280, please refer to Figure 6A~Figure 6C description of.
[0062] In addition, the above-mentioned method of forming the patterned protective layer 272 can also be completed by a laser lift-off process. Figure 3A~Figure 3C It is a schematic diagram of a laser lift-off process for forming a patterned protective layer. Please refer first Figure 3A After the thin film transistor 260 is formed, a protective layer 270 is formed on the gate insulating layer 220 and the thin film transistor 260. The material of the protective layer 270 is, for example, silicon nitride or silicon oxide, and the method for forming the protective layer 270 is, for example, physical vapor deposition. The method or chemical vapor deposition method is fully deposited on the substrate 200. Then as Figure 3B Then, a second mask S2 is provided above the protection layer 270, and the second mask S2 exposes a part of the protection layer 270. Then, the protective layer 270 is irradiated with the laser light L through the second mask S2, and the protective layer 270 irradiated by the laser light L absorbs the energy of the laser light L and peels off from the surface of the thin film transistor 260. After that, like Figure 3C As shown, after removing part of the protective layer 270 exposed by the second mask S2, a patterned protective layer 272 exposing the contact opening H is formed.
[0063] Of course, in other embodiments, the method of forming the patterned protective layer 272 can also be as follows Figure 4A~Figure 4C As shown. Please refer first Figure 4A After the thin film transistor 260 is formed, a photoresist layer 252 is formed on a portion of the drain electrode 244. Then as Figure 4B As shown, a protective layer 270 is formed to cover the gate insulating layer 220, the thin film transistor 260, and the photoresist layer 252. After that, like Figure 4C As shown, the photoresist layer 252 is removed, so that the protective layer 270 on the photoresist layer 252 is also removed, forming a patterned protective layer 272 exposing the contact opening H. In this embodiment, the method of removing the photoresist layer 252 is, for example, performing a lift-off process.
[0064] In addition, Figure 5A~Figure 5B Another method of forming a patterned protective layer is shown. Please refer first Figure 5A The method of forming the patterned protective layer 272 may be to form the protective layer 270 on the gate insulating layer 220 and the remaining second photoresist region 250b before removing the remaining second photoresist region 250b on. Next, please refer to Figure 5B After removing the remaining second photoresist block 250b, the protective layer 270 on the second photoresist block 250b is removed together to form a patterned protective layer 272. In this embodiment, the method of removing the photoresist layer 250b is, for example, performing a lift-off process.
[0065] In addition, the above-mentioned manufacturing method of forming the pixel electrode 282 can also be completed by a laser lift-off process. Figure 6A~Figure 6C It is a schematic diagram of a laser lift-off process for forming pixel electrodes. Please refer first Figure 6A After the patterned protective layer 272 is formed, an electrode material layer 280 is formed on the patterned protective layer 272. The method of forming the electrode material layer 280 is, for example, forming an indium tin oxide layer or an indium zinc oxide layer by sputtering. Then, like Figure 6B As shown, a third mask S3 is provided above the electrode material layer 280, and a part of the electrode material layer 280 is exposed by the third mask S3, and then the electrode material layer 280 is irradiated by the laser L through the third mask S3. Then, please refer to Figure 6C After removing part of the electrode material layer 280 exposed by the third mask S3, the pixel electrode 282 connected to the drain electrode 244 through the contact opening H is formed.
[0066] Of course, in other embodiments, the method of forming the pixel electrode 282 can also be as follows Figure 7A~Figure 7C As shown. Please refer first Figure 7A After the patterned protection layer 272 is formed, a photoresist layer 254 is formed on the patterned protection layer 272, wherein the photoresist layer 254 exposes part of the drain electrode 244. Then as Figure 7B As shown, the electrode material layer 280 is formed to cover the patterned protective layer 272, the drain electrode 244, and the photoresist layer 254. Then, please refer to Figure 7C , The photoresist layer 254 is removed, so that the electrode material layer 280 on the photoresist layer 254 is also removed, and the remaining electrode material layer 280 constitutes the pixel electrode 282. The above-mentioned method for removing the photoresist layer is for example a lift-off process.
[0067] In addition, Figure 8A~Figure 8D Another method of forming a patterned protective layer and pixel electrodes is shown. Such as Figure 8A As shown, a protective layer 270 is deposited on the gate insulating layer 220 and the thin film transistor 260, and then a photoresist layer 250 is formed on the protective layer 270. The photoresist layer 250 can be divided into a third photoresist The resist block 250c and the fourth photoresist block 250d. The third photoresist block 250c is located on the edge of the drain 244 and the edge of the storage capacitor C to prevent the second conductive layer 240 from being In the subsequent process, the thin film transistor 260 and the storage capacitor C are over-etched on the slope of the film layer stack to produce an undercut of the gate insulating layer 220, and the fourth photoresist block 250d is located in a part of the thin film transistor The thickness of the third photoresist block 250c is smaller than the thickness of the fourth photoresist block 250d, and the material of the photoresist layer 250 is, for example, an organic material. Next, please refer to Figure 8B , The protective layer 270 is etched using the photoresist layer 250 as a mask to expose a part of the drain electrode 244 of the thin film transistor 260 to form such Figure 8B The patterned protective layer 272 is shown.
[0068] Then, like Figure 8C As shown, the thickness of the photoresist layer 250 is reduced until the third photoresist block 250c is completely removed. After the third photoresist block 250c is completely removed, only the fourth photoresist block 250d is left, and then an electrode material layer 280 is deposited to cover the fourth photoresist block 250d and expose A portion of the drain electrode 244 of the transistor 260, a portion of the substrate 200, and the patterned protective layer 272 are removed, and then the remaining photoresist layer 250d is removed, so that the electrode material layer 280 on the remaining photoresist layer 250d Are removed at the same time, and the remaining conductive layer is formed as Figure 8D The illustrated pixel electrode 282 is electrically connected to the drain 244 of the transistor 260.
[0069] Based on the above, the present invention simultaneously fabricates the channel layer, the source electrode and the drain electrode, and therefore has the advantage of reducing the number of process steps compared to the known ones. In addition, the present invention uses laser L irradiation to form the gate instead of using the known photolithography etching process. Therefore, the method for manufacturing the pixel structure proposed in the present invention has at least the following advantages:
[0070] 1. In the manufacturing method of the pixel structure proposed in the present invention, the gate process does not need to use a photolithography process, so compared with the high-precision photomask process used in the photolithography process, the manufacturing cost of the photomask can be reduced.
[0071] 2. Since there are fewer processes for making pixel structures, lengthy photomask processes (such as photoresist coating, soft baking, hard baking, exposure, development, etching, photoresist stripping, etc.) can be reduced Defects in the production of pixel structures.
[0072] 3. The method of laser peeling off part of the protective layer proposed by the present invention can be applied to the repair of pixel electrodes in pixel repair, so as to remove the ITO residue that may remain in the pixel structure process to solve the problem between the pixel electrodes. The problem of short-circuit, thereby increasing the production yield.
[0073] Although the present invention has been disclosed as above in preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make slight changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection of the present invention The scope shall be subject to the scope defined by the appended claims.
