This invention claims the priority of Chinese Patent Application No. 201710144492.5 filed on Mar. 10, 2017, the entire contents of which are incorporated herein by reference.
This disclosure relates to the field of display, in particular, to a production method of an array substrate and an array substrate.
In the production of a thin film transistor (TFT) array substrate of a display panel, a low temperature polycrystalline oxide (LTPO) process is a novel technique which produces a TFT array substrate by concurrently using a low temperature polycrystalline silicon (LTPS) process and an oxide process.
An embodiment of this invention provides a production method of an array substrate, comprising the steps of: forming a polycrystalline silicon layer on a base, wherein the base comprises a first active area, a second active area, and a non-active area; forming an oxide semiconductor layer on the polycrystalline silicon layer; and forming a first active layer on the first active area and forming a second active layer on the second active area by using a single patterning process, wherein the first active layer is composed of the polycrystalline silicon layer, and the second active layer is composed of the oxide semiconductor layer and the polycrystalline silicon layer.
In one embodiment, the patterning process comprises the steps of: Step one: forming a first protective layer at the first active area and forming a second protective layer at the second active area by using a single mask, wherein the thickness of the first protective layer is less than that of the second protective layer; Step two: removing the oxide semiconductor layer and the polycrystalline silicon layer at the non-active area by etching; Step three: removing the whole of the first protective layer and a part of the second protective layer to expose the oxide semiconductor layer below the first protective layer; Step four: removing the exposed oxide semiconductor layer by etching to form the first active layer composed of the polycrystalline silicon layer; and Step five: removing the remainder of the second protective layer to form the second active layer composed of the oxide semiconductor layer and the polycrystalline silicon layer.
In one embodiment, it further comprises: a step of forming a passivation layer on the oxide semiconductor layer before performing the patterning process, wherein the patterning process comprises: Step one: forming a first protective layer at the first active area and forming a second protective layer at the second active area by using a single mask, wherein the thickness of the first protective layer is less than that of the second protective layer; Step two: removing the passivation layer, the oxide semiconductor layer, and the polycrystalline silicon layer at the non-active area by etching; Step three: removing the whole of the first protective layer and a part of the second protective layer to expose the passivation layer below the first protective layer; Step four: removing the exposed passivation layer and the oxide semiconductor layer therebelow by etching to form the first active layer composed of the polycrystalline silicon layer; and Step five: removing the remainder of the second protective layer to form the second active layer composed of the oxide semiconductor layer and the polycrystalline silicon layer, and remaining the passivation layer on the second active layer.
In one embodiment, the etching in the Step two and the Step four is dry etching.
In one embodiment without a passivation layer, in the Step two, the oxide semiconductor layer and the polycrystalline silicon layer at the non-active area are sequentially removed in an order of wet etching and dry etching, and in the Step four, the exposed oxide semiconductor layer is removed by wet etching.
In one embodiment with a passivation layer, in the Step two, the passivation layer, the oxide semiconductor layer, and the polycrystalline silicon layer at the non-active area are sequentially removed in an order of dry etching, wet etching, and dry etching.
In one embodiment with a passivation layer, in the Step four, the exposed passivation layer and the oxide semiconductor layer therebelow are sequentially removed in an order of wet etching and dry etching.
In one embodiment, the material of the oxide semiconductor layer comprises at least one of indium gallium zinc oxide, indium gallium oxide, indium tin zinc oxide, and aluminum zinc oxide.
In one embodiment with a passivation layer, it further comprises the steps of: forming a gate insulating layer; forming a first gate electrode in the first active area and a second gate electrode in the second active area; forming an interlayer insulating layer; and forming a first source electrode and a first drain electrode in the first active area, and a second source electrode and a second drain electrode in the second active area, wherein the first source electrode and the first drain electrode are each connected to the first active layer through a via hole which penetrates the interlayer insulating layer and the gate insulating layer, and the second source electrode and the second drain electrode are each connected to the second active layer through a via hole which penetrates the interlayer insulating layer, the gate insulating layer, and the passivation layer.
An embodiment of this invention further provides an array substrate, comprising: a base, a gate electrode insulating layer, at least one gate electrode, at least one source electrode, and at least one drain electrode, wherein the base has a first active area and a second active area, a first active layer is provided on the first active area and the first active layer is composed of a polycrystalline silicon layer, a second active layer is provided on the second active area and the second active layer is composed of a polycrystalline silicon layer and an oxide semiconductor layer formed on the polycrystalline silicon layer, and the polycrystalline silicon layer in the first active layer and the polycrystalline silicon layer in the second active layer are formed from the same polycrystalline silicon layer.
In one embodiment, a passivation layer is further provided above the second active layer.
In one embodiment, the material of the oxide semiconductor layer comprises at least one of indium gallium zinc oxide, indium gallium oxide, indium tin zinc oxide, and aluminum zinc oxide.
In one embodiment with a passivation layer, the array substrate further comprises an interlayer insulating layer, the at least one gate electrode comprises a first gate electrode and a second gate electrode, the at least one source electrode comprises a first source electrode and a second source electrode, the at least one drain electrode comprises a first drain electrode and a second drain electrode, the gate insulating layer is provided above the first active layer and the passivation layer, the first gate electrode and the second gate electrode are provided above the gate insulating layer, the interlayer insulating layer is provided above the first gate electrode and the second gate electrode, the first source electrode, the first drain electrode, the second source electrode, and the second drain electrode are formed above the interlayer insulating layer, wherein the first source electrode and the first drain electrode are each connected to the first active layer through a via hole which penetrates the interlayer insulating layer and the gate insulating layer, and the second source electrode and the second drain electrode are each connected to the second active layer through a via hole which penetrates the interlayer insulating layer, the gate insulating layer, and the passivation layer.
In order to illustrate the technical solutions in embodiments of this invention more clearly, accompanying drawings of embodiments will be simply illustrated below. It is apparent that the accompanying drawings described below are merely some embodiments related to this invention but not limitations of this invention.
This disclosure may provide a production method of an array substrate, which can simplify the procedures and improve the production, as well as an array substrate.
In this disclosure, since an active layer of an LTPS TFT and an active layer of an oxide TFT can be concurrently formed by a single patterning process, the procedures can be simplified and the production can be improved. Furthermore, since the active layer of the oxide TFT array substrate comprises an oxide semiconductor layer and a polycrystalline silicon layer therebelow, it is advantageous to block ultraviolet by forming the polycrystalline silicon layer below the oxide semiconductor layer for the oxide semiconductor layer which is highly sensitive to ultraviolet.
In order to enable objects, technical solutions, and advantages of embodiments of this invention to be clearer, technical solutions of embodiments of this invention will be described clearly and fully below in conjunction with accompanying drawings of embodiments of this invention. Obviously, the embodiments described are a part of the embodiments of this invention, rather than all embodiments. Based on the embodiments described of this invention, all other embodiments obtained by those of ordinary skill in the art without performing inventive work belong to the scope protected by this invention.
Unless defined otherwise, technical terms or scientific terms used in this disclosure should have general meanings as understood by those of ordinary skill in the art to which this invention belongs. The word, such as “first”, “second”, or the like, used in this disclosure does not represent any order, number, or importance, but is used to distinguish different structural parts. The word, such as “include”, “comprise”, “have”, or the like, used in this disclosure means that the element or article occurring before this word encompasses the element or article and the equivalent thereof enumerated after this word and does not exclude other elements or articles. The word, such as “above”, “below”, or the like, is only used to indicate a relative position relationship. After the absolute position of a described object is changed, the relative position relationship may be changed accordingly.
In this disclosure, a “first/second active area” refers to an area where a first active layer or a second active layer is formed. A “non-active area” refers to an area where neither a first active layer nor a second active layer is formed and the base needs to be exposed by etching. However, another active layer, except a first active layer or a second active layer, may be otherwise formed in the non-active area according to practical needs, and this is encompassed in the scope of this invention.
Meanings of reference numerals in the drawings are as follows: 1, 11—LTPS TFT; 2, 22—oxide TFT; 10, 110—substrate; 20—buffering layer; 30, 130—polycrystalline silicon layer (low temperature polycrystalline silicon layer); 40, 140—oxide semiconductor layer; 50—passivation layer; 201, 1201—gate electrode insulating layer; 102, 202, 1102, 1202—gate electrode; 203, 1203—interlayer insulating layer; 104, 204, 1104, 1204—source electrode; 105, 205, 1105, 1205—drain electrode.
As shown in
This invention is achieved in order to at least partly solve the technical problem described above, and is described in detail below in conjunction with specific embodiments.
As shown in
Furthermore, as shown in
Here, the substrate 10 is, for example, a glass substrate. Furthermore, the gate electrode insulating layer 201 may be composed of, for example, silicon dioxide or silicon nitride. The interlayer insulating layer 203 may also be composed of, for example, silicon dioxide or silicon nitride. The buffering layer 20 may be formed by using the prior art, and detailed description is not made herein.
As shown in
As shown in
As shown in
As shown in
Since the first photoresist layer 108 and the second photoresist layer 208 can be concurrently formed by using one mask in the same photolithographic procedure, the photolithographic procedure can be simplified and the production can be improved for an existing plant so as to increase the profit, and the investment cost can be effectively reduced for a newly established plant.
As shown in
Furthermore, the etching in step S105 may be performed according to the process flow in
First, as shown in
Then, as shown in
Then, as shown in
Finally, as shown in
The procedure of forming the active layer of the LTPO TFT is complete by the above steps. As described above, in this embodiment, the active layer of the LTPS TFT 1 and the active layer of the oxide TFT 2 are formed by using a single patterning process (using one mask and performing a single photolithographic procedure).
After the active layer is formed, the procedures of forming gate electrode insulating layers, gate electrodes, interlayer insulating layers, source electrodes, and drain electrodes of the LTPS TFT 1 and the oxide TFT 2 are the same as those in the prior art, and therefore detailed description is not made herein. Concerning a contact region in the oxide TFT 2, since this contact region will become conductive when the interlayer insulating layer 203 is etched, there is no problem with contact.
After the source electrode and the drain electrode of the LTPS TFT 1 and the source electrode and the drain electrode of the oxide TFT 2 are formed, desirable layers may be formed according to the requirements of liquid crystal displays (LCDs) or organic light emitting diodes (OLEDs), and detailed description is not made herein.
With respect to the production method of the LTPO TFT array substrate according to an embodiment of this invention, since the active layer of the LTPS TFT and the active layer of the oxide TFT may be formed by using only one mask in the same photolithographic procedure, the procedures can be simplified and the production can be improved so as to increase the profitability.
Furthermore, in the LTPO TFT array substrate in an embodiment of this invention, the active layer of the oxide TFT 2 is composed of the oxide semiconductor layer 40 and the polycrystalline silicon layer 30 therebelow. Since the oxide semiconductor layer is highly sensitive to ultraviolet, it is advantageous to block ultraviolet by the polycrystalline silicon layer 30 below the oxide semiconductor layer 40.
The following points should be demonstrated: (1) the accompanying drawings of the embodiments of this invention merely relate to the structures related to the embodiments of this invention, and with respect to other structures, general designs may be referred to; and (2) thicknesses and shapes of various layers in the accompanying drawings do not reflect real ratios, and the object thereof is merely to exemplarily illustrate the embodiments of this invention.
Those described above are merely exemplary embodiments of this invention, but are not intended to limit the scope of this invention. The scope protected by this invention is determined by the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
201710144492.5 | Mar 2017 | CN | national |