WO2018214740A1

WO2018214740A1 - Display substrate, method for manufacturing same, and display device

Info

Publication number: WO2018214740A1
Application number: PCT/CN2018/086297
Authority: WO
Inventors: 宫奎
Original assignee: 京东方科技集团股份有限公司; 合肥京东方光电科技有限公司
Priority date: 2017-05-26
Filing date: 2018-05-10
Publication date: 2018-11-29
Also published as: CN107037655A

Abstract

A display substrate, a method for manufacturing same, and a display device. At least a part of a first signal line (1) of the display substrate comprises at least two layers of conductive lines that are stacked. In a direction perpendicular to a first direction, the conductive line closest to a base (100) is wider than the other conductive line, and the long edge of the orthographic projection of the conductive line closest to the base (100) on the base (100) extending along the first direction is located outside the long edge of the orthographic projection of the other conductive line on the base (100) extending along the first direction. According to the first signal line (1) having the above structure, steps between the bottoms of the two sides of the signal line and surrounding regions can be reduced, and rubbing alignment of an alignment film at the bottoms of the steps at the two sides of the signal line is facilitated, and thus, the problem of light leak occurring to the parts at the two sides of the signal line is resolved, the brightness and chromaticity of a display product are uniform, and the display quality is improved.

Description

Display substrate, manufacturing method thereof, and display device

The present application claims priority to Chinese Patent Application No. 201710384896.1, filed on May 26, s.

Technical field

Embodiments of the present invention relate to a display substrate, a method of fabricating the same, and a display device.

Background technique

The main structure of the liquid crystal display device includes a backlight, an array substrate of the pair of boxes, and a color filter substrate, and a liquid crystal layer filled between the array substrate and the color filter substrate. The display principle is as follows: the voltage is used to control different states of the liquid crystal molecules, so that the light of the backlight penetrates the liquid crystal layer in a desired polarization direction, and presents different colors and patterns.

In order to realize the display, it is necessary to regularly arrange the liquid crystal molecules. Therefore, an alignment film is added on the upper and lower surfaces of the liquid crystal layer, and the liquid crystal molecules are arranged along the direction of the alignment film and at a certain angle with the substrate. When a voltage is applied to the liquid crystal layer, liquid crystal molecules are deflected to produce photoelectric characteristics. The main method for forming the alignment film is to apply the alignment liquid on the inner side of the array substrate and the color filter substrate, and then perform a rubbing process. In the rubbing process, the surface of the alignment film is rubbed by the hairiness of the rubbing cloth on the orientation roller, and the brush is pressed out according to the surface. The grooves aligned in a certain direction complete the orientation of the alignment film.

Since the alignment film needs to be placed in contact with the liquid crystal layer, the alignment film is formed only after the other structures of the substrate are completed. Therefore, the structure on the substrate tends to affect the rubbing orientation of the alignment film, especially a signal line having an angle greater than zero between the orientation directions. Since there is a step difference between the signal line and the peripheral region, the alignment film at the bottom of the difference between the two sides of the signal line is not easily brushed out of the alignment groove during the rubbing alignment of the alignment film, causing the display device to be in the signal Light leakage occurs in the parts on both sides of the line, which makes the brightness and chromaticity of the display device uneven, which affects the image quality.

Summary of the invention

An embodiment of the present invention provides a display substrate including a substrate and a first signal line disposed on the substrate, the first signal line extending along a first direction, and at least a portion of the first signal line includes at least two Conductive lines stacked in layers; in a direction perpendicular to the first direction, the width of the conductive line closest to the substrate is greater than the width of the other conductive lines, and the conductive line closest to the substrate is positive on the substrate The long side of the projection extending in the first direction is located outside the long side of the orthographic projection of the other conductive line on the substrate extending in the first direction.

For example, in the display substrate as described above, for any two adjacent conductive lines, the width of the conductive line close to the substrate is greater than the width of the other conductive line, and the conductive line near the substrate is on the substrate The long side of the orthographic projection extending in the first direction is located outside the long side of the orthogonal projection of the other conductive line on the substrate extending in the first direction.

For example, in the display substrate as described above, the thickness of the at least two layers of conductive lines is the same in a direction perpendicular to the substrate.

For example, in the display substrate as described above, at least a portion of the first signal line is composed of a first conductive line and a second conductive line, the first conductive line being closer to the substrate than the second conductive line, The first conductive line is made of Al, and the second conductive line is made of Mo.

For example, the display substrate is a thin film transistor array substrate, the first signal line is a data line, and the display substrate further includes an alignment film, and an orientation direction of the alignment film is perpendicular to the first direction.

Embodiments of the present invention also provide a display device including the display substrate as described above.

The embodiment of the invention further provides a method for manufacturing a display substrate as described above, comprising:

Forming a first signal line on a substrate;

Forming an alignment film on a side of the first signal line facing away from the substrate, the first signal line extending along a first direction, and the step of forming the first signal line includes:

Forming at least two layers of conductive lines stacked; in a direction perpendicular to the first direction, a width of the conductive line closest to the substrate is greater than a width of the other conductive lines, and a conductive line closest to the substrate is on the substrate The long side of the upper orthographic projection extending in the first direction is located outside the first side of the long side of the orthographic projection of the other conductive line on the substrate.

For example, in the manufacturing method as described above, the step of forming the first signal line includes:

Forming at least two conductive layers in sequence, each conductive layer being used to form a conductive line of the first signal line;

Forming a photoresist on the at least two conductive layers, exposing the photoresist, developing a photoresist non-retained region, and a photoresist retention region, wherein the photoresist retention region corresponds to at least the a region where the first signal line is located, the photoresist retention region includes a first remaining region of the photoresist and a second remaining region of the photoresist, wherein a thickness of the photoresist of the first remaining region of the photoresist is less than a thickness of the photoresist in the second remaining region of the photoresist, the first remaining region of the photoresist being located at an outermost periphery of the photoresist retention region in a direction perpendicular to the first direction;

Removing the at least two conductive layers of the photoresist non-retained region;

Removing the photoresist of the first remaining region of the photoresist by an ashing process, removing the conductive layer other than the conductive layer closest to the substrate of the first remaining region of the photoresist so as to be perpendicular to the first direction In the direction, the width of the conductive line closest to the substrate is greater than the width of the other conductive lines, and the long side of the orthographic projection of the conductive line closest to the substrate extending in the first direction on the substrate is located at other conductive lines. The outer side of the long side extending in the first direction of the orthographic projection on the substrate.

For example, in the manufacturing method as described above, the first signal line is composed of a first conductive line and a second conductive line, and the step of forming the first signal line includes:

Forming a first conductive layer and a second conductive layer in sequence;

Forming a photoresist on the second conductive layer, exposing the photoresist, developing a photoresist non-retained region, and a photoresist retention region, wherein the photoresist retention region at least corresponds to the first a region where a signal line is located, the photoresist retention region includes a photoresist portion remaining region and a photoresist completely remaining region, wherein the photoresist portion retention region is located in a direction perpendicular to the first direction The photoresist completely retains the periphery of the area;

Removing the first conductive layer and the second conductive layer of the photoresist non-retained region, the first conductive line is formed by the first conductive layer, and a transition layer is formed by the second conductive layer;

Removing the photoresist of the remaining portion of the photoresist by an ashing process, and removing the second conductive layer of the remaining portion of the photoresist portion;

The photoresist in the completely remaining region of the photoresist is stripped, and the second conductive line is formed by the transition layer.

The manufacturing method as described above, wherein the first conductive layer and the second conductive layer of the photoresist non-retained region are removed by a wet etching process;

The second conductive layer of the remaining portion of the photoresist portion is removed by a dry etching process.

DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings of the embodiments will be briefly described below. It is obvious that the drawings in the following description relate only to some embodiments of the present invention, and are not intended to limit the present invention. .

1 is a partial structural view showing a display substrate in an embodiment of the present invention;

Figure 2 shows a plan view of Figure 1;

3 to FIG. 6 are schematic diagrams showing a manufacturing process of a display substrate in an embodiment of the present invention;

Figure 7 is a plan view showing a display substrate in an embodiment of the present invention;

Figure 8 is a partial cross-sectional view along line A-A of Figure 7.

detailed description

The technical solutions of the embodiments of the present invention will be clearly and completely described in the following with reference to the accompanying drawings. It is apparent that the described embodiments are part of the embodiments of the invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the described embodiments of the present invention without departing from the scope of the invention are within the scope of the invention.

Unless otherwise defined, technical terms or scientific terms used herein shall be taken to mean the ordinary meaning of the ordinary skill in the art to which the invention pertains. The words "first," "second," and similar terms used in the present disclosure do not denote any order, quantity, or importance, but are used to distinguish different components. Similarly, the words "comprising" or "comprising" or "comprising" or "an" or "an" The words "connected" or "connected" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Upper", "lower", "left", "right", etc. are only used to indicate the relative positional relationship, and when the absolute position of the object to be described is changed, the relative positional relationship may also change accordingly.

For the liquid crystal display technology, the liquid crystal is oriented by providing an alignment film, and the liquid crystal molecules are arranged in a regular order to realize a display function. In the prior art, the orientation of the alignment film is achieved by forming an orientation groove on the surface of the alignment film by a rubbing process. Wherein, the alignment film is disposed on the outermost side of the display substrate, and after the display panel is formed on the case, the alignment film is placed in contact with the liquid crystal. Since the alignment film is disposed at the outermost side of the display substrate, when there is an angle greater than zero between the extending direction of the signal line of the display substrate and the orientation direction of the alignment film located thereon, there is a step difference between the signal line and the peripheral region. During the rubbing orientation of the alignment film, the alignment film at the bottom of the step on both sides of the signal line is not easily rubbed out of the alignment trench, causing light leakage on portions of the signal line, causing brightness of the display device, Uneven chromaticity affects image quality.

The embodiment of the present disclosure shows that the signal line of the substrate includes at least two layers of conductive lines stacked, and the line width of the conductive line closest to the substrate of the display substrate is the largest, and the long side of the conductive line closest to the substrate is located at the long side of the other conductive line. The outer side of the signal line reduces the step difference between the bottom portion and the peripheral portion on both sides of the signal line, thereby facilitating the rubbing orientation of the alignment film at the bottom of the step on both sides of the signal line, thereby overcoming the light leakage phenomenon and improving the display quality.

Specific embodiments of the present invention will be further described in detail below with reference to the drawings and embodiments. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

Embodiment 1

As shown in FIG. 1 and FIG. 2, in this embodiment, a display substrate including a substrate 100 and a first signal line 1 disposed on the substrate 100, and a first signal line 1 disposed away from the substrate is provided. An orientation film (not shown) on one side of 100, the first signal line 1 extends in the first direction, and an orientation angle of the alignment film and the first direction has an angle greater than zero.

At least a portion of the first signal line 1 includes at least two layers of conductive lines stacked; in a direction perpendicular to the first direction, a width of the conductive line closest to the substrate 100 is greater than a width of the other conductive lines, and is closest to the substrate 100 The long side of the orthographic projection of the conductive line on the substrate 100 extending in the first direction is located outside the long side of the positive projection of the other conductive line on the substrate 100 extending in the first direction. That is, the first orthographic projection of the other conductive line on the substrate 100 is located within the second orthographic projection of the conductive line closest to the substrate 100 on the substrate 100, and the long side and the second of the first orthographic projection extending in the first direction The distance between the long sides of the orthographic projection extending in the first direction is greater than zero.

In the above technical solution, the first signal line having the above structure can reduce the step difference between the bottom portion on both sides of the signal line and the peripheral region, and facilitate the rubbing orientation of the alignment film at the bottom of the difference between the two sides of the signal line, thereby overcoming the The problem of light leakage occurs in the parts on both sides of the signal line.

It should be noted that, in this embodiment, the first signal line 1 extends in the first direction, and the width of the first signal line 1 is defined as: the extending distance of the first signal line 1 in a direction perpendicular to the first direction, The length of the first signal line 1 refers to the extension distance of the first signal line 1 in the first direction. The two sides of the first signal line 1 refer to opposite sides of the first signal line 1 in a direction perpendicular to the first direction. Since the width of the first signal line 1 is small, the influence on the rubbing orientation of the alignment film located above it is small, and may be disregarded.

Wherein the alignment film is disposed above the first signal line on a side of the first signal line that faces away from the substrate. For example, the alignment film is located on the outermost side of the display substrate, and after the display panel is formed by the process of the counter, the alignment film is placed in contact with the liquid crystal to realize alignment of the liquid crystal molecules.

The angle between the orientation direction of the alignment film and the first direction in the present embodiment means an angle between the orientation direction of the alignment film on both sides of the first signal line 1 and the first direction. Since the step difference between the both sides of the first signal line 1 and the peripheral region affects the orientation of the alignment film located above it.

In the actual application process, the orientation direction of the alignment film is not limited to one direction, for example, the orientation groove of the alignment film may be a polygonal line shape. Then, an angle between a portion of a first signal line and an orientation direction of the alignment film located on both sides of the portion may be equal to zero, that is, an orientation direction of the alignment film located on both sides of the portion and the first direction The angle between them is equal to zero. The angle between the other portion of the first signal line and the orientation direction of the alignment film on both sides of the other portion is greater than zero, which may occur when the alignment groove of the alignment film is in a zigzag shape. In this case, the other portion of the first signal line may be composed of at least two layers of conductive lines having the above structure, or the entire first signal line may be composed of at least two layers of conductive lines having the above structure. To overcome the problem of light leakage at the portions on both sides of the first signal line.

In order to simplify the fabrication process, in the present embodiment, the entire first signal line 1 is disposed by at least two layers of conductive lines stacked.

For example, in a direction perpendicular to the substrate 100, the thickness of the at least two layers of conductive lines may be set to be the same.

Further, for any two adjacent conductive lines, the width of the conductive line near the substrate 100 is greater than the width of the other conductive line, and the long side of the orthographic projection of the conductive line near the substrate 100 on the substrate 100 is located at another conductive line. The line is outside the long side of the orthographic projection on the substrate 100, that is, from the side close to the substrate 100 to the side away from the substrate 100, the width of the conductive line of the first signal line 1 is reduced layer by layer, in a stepped shape, The step difference between the conductive line and the peripheral region is gradually increased, and the large steepness is prevented from affecting the rubbing orientation of the alignment film at the bottom of the step on both sides of the first signal line 1.

In one embodiment, at least a portion of the first signal line 1 is disposed to be composed of two layers of conductive lines, wherein a width of the conductive line adjacent to the substrate 100 is greater than a width of the other conductive line, and a conductive line adjacent to the substrate 100 is on the substrate 100. The long side of the upper orthographic projection is located outside the long side of the orthographic projection of the other conductive line on the substrate 100, so that the problem of light leakage at the portions on both sides of the first signal line 1 can be effectively solved. At the same time, the structure of the first signal line 1 is relatively simple, which is convenient for the realization of the manufacturing process.

In this embodiment, for example, the first signal line 1 may be provided of two layers of conductive wires having the same thickness.

Further, the entire first signal line 1 is arranged to be composed of two layers of conductive lines to simplify the structure of the first signal line 1.

The first signal line 1 in the above embodiment can solve the problem of the light leakage phenomenon in the portion on both sides of the first signal line 1, and can also simplify the manufacturing process of the first signal line 1.

Since at least a portion of the first signal line 1 is composed of at least two layers of conductive lines stacked, and the pattern of the conductive lines closest to the substrate 100 is different from the pattern of other conductive lines, the process of preventing the other conductive lines from being formed is closest to the substrate. For the conductive line of 100, the material of the conductive line closest to the substrate 100 needs to be different from the material of the other conductive lines, so that the fabrication of the first signal line 1 having the above structure can be completed by using different etching processes.

The description will be made by taking an example in which at least a part of the first signal line 1 is composed of two layers of conductive lines stacked in a stack.

When at least a portion of the first signal line 1 is composed of two layers of conductive lines stacked, one of the conductive lines is defined as a first conductive line 11 and the other conductive line is a second conductive line 12, the first conductive line 11 is opposite The second conductive line 12 is closer to the substrate 100. The width of the first conductive line 11 is greater than the width of the second conductive line 12 in a direction perpendicular to the first direction, and the long side of the first conductive line 11 extending in the first direction of the orthographic projection on the substrate 100 is located at the The second conductive line 12 is on the outside of the long side of the orthographic projection in the first direction on the substrate 100. Wherein, the first conductive line 11 is made of Al, and the second conductive line 12 is made of Mo. In the process of fabricating the first signal line 1, the metal Mo layer can be quickly dry etched with SF6 and O2 as etching gases, and the metal Al layer is highly resistant to dry etching because of the O In the plasma environment, a layer of Al2O3 is formed on the surface of the metal Al. Al2O3 is a ceramic material and is hardly etched by dry etching. When the metal Mo layer is etched by a dry etching process, the Al2O3 layer is formed. The first conductive line 11 can be protected from being damaged by the plasma, so that at least a part of the first signal line 1 having the above structure can be formed. For example, the first conductive line and the second conductive line may be formed by one patterning process (including coating of photoresist, exposure and development, etching process, photoresist stripping, etc.), and may also pass two independent patterns. The process forms the first conductive line and the second conductive line, and the specific process will be described in the following.

Further, the thicknesses of the first conductive line 11 and the second conductive line 12 may be set to be the same. And the entire first signal line 1 is composed of the first conductive line 11 and the second conductive line 12 to simplify the structure of the first signal line 1.

Referring to FIG. 7 and FIG. 8 , the technical solution of the present invention will be specifically described below by taking the display substrate as a thin film transistor array substrate as an example.

The first signal line 1 may be, for example, a data line, and an orientation direction of the alignment film may be perpendicular to the first direction. Of course, the first signal line 1 can also be a gate line, a common electrode line, etc., and the technical solution of the present invention can be applied to solve the problem of light leakage caused by the step difference on both sides of the first signal line 1. Hereinafter, only the first signal line 1 is taken as a data line for illustration.

The thin film transistor array substrate includes:

a transparent substrate 100, such as: glass substrate 100, quartz substrate 100, organic resin substrate 100;

The horizontally and vertically distributed gate lines 2 and the data lines 1 disposed on the substrate 100 define a plurality of pixel regions, each of which includes a thin film transistor 5 and a pixel electrode (not shown), of the thin film transistor 5 The gate electrode may be integrally formed with the gate line 2 and made of the same gate metal layer; the source electrode may be integrally formed with the data line 1 and made of the same source/drain metal layer; the drain electrode 50 is electrically connected to the pixel electrode, and the data line 1 is The transmitted pixel voltage is transmitted to the pixel electrode through the thin film transistor 5 for forming an electric field that drives deflection of the liquid crystal molecules;

Covering the passivation layer 101 of the thin film transistor 5;

An alignment film (not shown) disposed on the passivation layer 101;

The data line 1 extends in the first direction and is perpendicular to the orientation direction of the alignment film. The data line 1 is composed of a first conductive line 11 made of metal Al and a second conductive line 12 made of metal Mo. The first conductive line 11 is closer to the substrate 100 than the second conductive line 12. The width of the first conductive line 11 is greater than the width of the second conductive line 12 in a direction perpendicular to the first direction, and the long side of the first conductive line 11 extending in the first direction of the orthographic projection on the substrate 100 An outer side of the long side of the second conductive line 12 extending in the first direction of the orthographic projection on the substrate 100.

As for the position between other structures and structures of the thin film transistor array substrate, a known technique can be referred to, for example, the positional relationship between the gate electrode, the source electrode, the drain electrode and the active layer pattern 51 of the thin film transistor 5 can be based on the thin film transistor 5 The type is set up and will not be repeated here.

In this embodiment, a display device is further provided, comprising the display substrate as described above, for solving the problem that the two sides of the signal line have a large step difference with the peripheral region, affecting the rubbing orientation of the alignment film, thereby causing light leakage, so that Display the brightness and chromaticity of the product to improve the display quality.

The display device may be a liquid crystal display panel or a liquid crystal display device.

Of course, the embodiments of the present invention are also applicable to other electronic devices to solve the defect caused by excessive step difference by reducing the step difference between the signal line and the peripheral region, and are not limited to application to the liquid crystal display device.

Embodiment 2

As shown in FIG. 1 and FIG. 2, in this embodiment, a method for fabricating a display substrate in the first embodiment is provided, including:

Forming a first signal line 1 on a substrate 100;

An alignment film is formed on a side of the first signal line 1 away from the substrate 100, and the first signal line 1 extends in the first direction. The step of forming the first signal line 1 includes:

Forming at least two layers of conductive lines stacked; in a direction perpendicular to the first direction, the width of the conductive line closest to the substrate 100 is greater than the width of the other conductive lines, and the conductive line closest to the substrate 100 is The long side of the orthographic projection on the substrate 100 is located outside the long side of the orthographic projection of the other conductive lines on the substrate 100.

At least a portion of the first signal line obtained by the above steps is composed of at least two layers of conductive lines stacked, and the at least two layers of conductive lines have the above structure, which can reduce the distance between the bottom portion and the peripheral portion on both sides of the signal line The step is different when the orientation direction of the alignment film and the first direction have an angle greater than zero, which facilitates the rubbing orientation of the alignment film at the bottom of the difference between the two sides of the signal line, and overcomes the leakage of light on both sides of the signal line. The problem of the phenomenon, improve the display quality.

For example, the thickness of the conductive layer closest to the substrate 100 is set for the purpose of overcoming light leakage at portions on both sides of the signal line. The conductive layer closest to the substrate 100 may be a single layer structure or a composite layer structure.

Of course, each conductive layer of the first signal line 1 may be a single layer structure or a composite layer structure.

In this embodiment, the step of forming the first signal line includes:

Removing the photoresist of the first remaining region of the photoresist by an ashing process, removing the conductive layer other than the conductive layer closest to the substrate of the first remaining region of the photoresist so as to be perpendicular to the first direction In the direction, the width of the conductive line closest to the substrate is greater than the width of the other conductive lines, and the long side of the orthographic projection of the conductive line closest to the substrate on the substrate is located on the other conductive line on the substrate. The outer side of the long side of the orthographic projection.

Wherein, the thickness of the at least two conductive layers may be the same.

The above steps form the first signal line of the present invention by one patterning process. The patterning process includes two etching processes, and forms a pattern of the first signal line by a first etching process, and removes other conductive layers other than the conductive layer closest to the substrate by a second etching process to expose The two sides of the conductive layer of the substrate are closest to each other, thereby reducing the step difference between the bottom portion on both sides of the first signal line and the peripheral region. Of course, each of the conductive lines of the first signal line of the present invention can also be separately separated by a separate patterning process.

Obviously, the second etching process described above removes only the conductive layer other than the conductive layer closest to the substrate, and does not have an etching effect on the conductive layer closest to the substrate, so as to expose the conductive closest to the substrate. Both sides of the layer, i.e., expose the sides of the conductive line closest to the substrate.

In order to achieve the above object, the material of the conductive line closest to the substrate needs to be different from the material of other conductive lines. For example, the material of the conductive line closest to the substrate is metal Al, and the material of other conductive lines is metal Mo. The second etching process is a rapid dry etching using SF6 and O2 as etching gases. Since the metal Al layer is highly resistant to dry etching, this is because in the O plasma environment, a layer of Al2O3 is formed on the surface of the metal Al, and Al2O3 is a ceramic material which is hardly dry-etched. The plasma is damaged so that in the second etching process, the conductive line closest to the substrate is not etched, and by etching other conductive layers located thereon, the conductive line closest to the substrate can be exposed. On both sides.

In order to simplify the process, the entire first signal line may be composed of at least two layers of conductive lines stacked, and the structure is uniform.

Further, based on the same purpose, as shown in FIG. 1 , the first signal line 1 may be further composed of the first conductive line 11 and the second conductive line 12, thereby effectively solving the partial generation of the first signal line 1 on both sides. The problem of light leakage. At the same time, the structure of the first signal line 1 is relatively simple, which is convenient for the realization of the production process. The step of forming the first signal line 1 includes:

Forming a first conductive layer 20 for forming a first conductive line 11 and a second conductive layer 30 for forming a second conductive line 12, as shown in FIG. 3 and FIG. ;

Forming a photoresist on the second conductive layer 30, exposing the photoresist, forming a photoresist non-retained region and a photoresist retention region after development, the photoresist retention region corresponding to at least the first In the region where the signal line is located, the photoresist retention region includes a photoresist portion retention region 42 and a photoresist completely remaining region 41. In a direction perpendicular to the first direction, the photoresist portion retention region 42 is located in the photolithography. The glue completely retains the periphery of the region 41 as shown in FIG. 4;

Removing the first conductive layer and the second conductive layer of the photoresist non-retained region, the first conductive layer 11 is formed by the first conductive layer, and a transition layer 31 is formed by the second conductive layer, as shown in FIG. Shown

Removing the photoresist of the remaining portion of the photoresist by an ashing process, as shown in FIG. 6, removing the second conductive layer of the photoresist portion remaining region;

The photoresist in the completely remaining region of the photoresist is stripped, and the second conductive line 12 is formed by the transition layer 31, as shown in FIG. 6 and FIG.

The thickness of the first conductive layer 20 and the second conductive layer 30 may be the same.

In the above step, the first conductive layer 20 and the second conductive layer 30 of the photoresist non-retained region are removed by a wet etching process; and the second conductive layer 30 of the remaining portion of the photoresist is removed by a dry etching process. In order to achieve the purpose of the two etching processes, the material of the first conductive layer 20 is metal Al, and the material of the second conductive layer 30 is metal Mo, so that the wet etching process can simultaneously remove the non-retained region of the photoresist. The first conductive layer 20 and the second conductive layer 30 are described. The dry etching process can only remove the second conductive layer 30 of the remaining portion of the photoresist portion, and the first conductive layer 20 is not etched. The specific principle has been detailed in the above.

Of course, the material of the first conductive layer 20 is not limited to the metal Al, and the material of the second conductive layer 30 is not limited to the metal Mo, as long as the above object can be achieved.

The technical solution of the present invention will be described below by taking the display substrate as a thin film transistor array substrate as an example.

The first signal line 1 is, for example, a data line, and an orientation direction of the alignment film is perpendicular to the first direction.

The manufacturing method of the thin film transistor array substrate includes:

In step S1, a substrate 100 is provided, and gate lines 2 and data lines 1 distributed transversely and vertically are formed on the substrate 100 to define a plurality of pixel regions. The thin film transistor 5 is formed in each pixel region, and the gate electrode 2 and the gate electrode of the thin film transistor 5 are formed of the same gate metal layer and integrally formed; the data line 1 and the source electrode and the drain electrode 50 of the thin film transistor 5 are made of the same source and drain metal. a layer is formed, and the data line 1 is integrally formed with the source electrode, as shown in FIG. 7;

The step of forming the thin film transistor 5 further includes forming a gate insulating layer and an active layer pattern 51. The material of the gate insulating layer is SiNx, SiOx or Si(ON)x, and may be a single layer structure or a multilayer structure. The material of the active layer pattern 51 is a semiconductor material such as a silicon semiconductor or a metal oxide.

The material of the gate metal layer is a metal such as Cu, Al, Ag, Mo, Cr, Nd, Ni, Mn, Ti, Ta, W, and an alloy of these metals, and the gate electrode and the gate line may be a single layer structure or a plurality of layers. Structure, multilayer structure such as Cu\Mo, Ti\Cu\Ti, Mo\Al\Mo, etc.

For example, the gate metal layer and the source/drain metal layer can be deposited by a magnetron sputtering process.

The source/drain metal layer is composed of two layers of conductive layers stacked, and the obtained data line 1 is composed of two layers of first conductive lines 11 and second conductive lines 12 stacked. The material of the second conductive line 12 away from the substrate 100 is a metal that is easily etched by plasma, such as metal Mo, etc., and the material of the first conductive line 11 near the substrate 100 is a metal that is not easily etched by plasma, for example, Metal Al, etc. The first conductive line 11 and the second conductive line 12 have the same thickness, and are about 250 nm.

Wherein, in combination with FIG. 3-6, the steps of forming the data line 1 include:

Forming the first conductive layer 20 and the second conductive layer 30 sequentially by a magnetron sputtering process, as shown in FIG. 3;

Forming a photoresist on the second conductive layer 30, exposing the photoresist to form a photoresist non-retained region and a photoresist retention region, wherein the photoresist retention region corresponds to at least the data line In the region where the photoresist remains, the photoresist portion retention region 42 and the photoresist completely remaining region 41 are in the direction perpendicular to the first direction, and the photoresist portion retention region 42 is completely in the photoresist. The periphery of the region 41 is reserved and symmetrically distributed on both sides of the photoresist completely reserved region 41, as shown in FIG. 4;

Removing the first conductive layer and the second conductive layer of the photoresist non-reserved region by a wet etching process, the first conductive layer 11 is formed by the first conductive layer, and a transition is formed by the second conductive layer Layer 31, as shown in FIG. 5;

Removing the photoresist in the remaining portion of the photoresist by an ashing process, and removing the second conductive layer of the remaining portion of the photoresist by a dry etching process using SF6 and O2 as etching gases, A conductive layer is made of metal Al. In the O plasma environment, a layer of Al2O3 is formed on the surface of the metal Al layer, and Al2O3 is a ceramic material, which is hardly etched, so that the first layer can be protected. A conductive layer is not damaged by the plasma;

The photoresist in the completely remaining region of the photoresist is stripped, and the second conductive line 12 is formed from the transition layer, as shown in FIG. 6 and FIG.

This completes the production of data line 1.

It should be noted that the photoresist completely reserved region in the above step also corresponds to the region where the source electrode and the gate electrode of the thin film transistor 5 are located.

Step S2, forming a passivation layer 101 covering the thin film transistor 5 by vapor deposition, as shown in FIG. 8;

Step S3, forming an alignment film on the passivation layer, and performing rubbing alignment on the alignment film to form an alignment trench perpendicular to the data line.

The fabrication of the thin film transistor array substrate has thus been completed.

As shown in FIG. 8, the thin film transistor array substrate obtained by the above steps has a data line composed of a first conductive line 11 and a second conductive line 12 in a stepped structure. The step difference h=H/2 between the first conductive line 11 and the peripheral region is smaller than the maximum thickness H of the first signal line 1, and the step difference between the bottom portion on both sides of the first signal line 1 and the peripheral region is reduced. The data line 1 is covered with a passivation layer 101. The passivation layer 101 is disposed on the passivation layer 101 due to a step difference between the data line 1 and the peripheral region. Since the step difference between the bottom portion and the peripheral region on both sides of the data line 1 is reduced, the step difference between the bottom portion of the passivation layer 101 and the peripheral region is also reduced, which also contributes to the bottom of the step of the passivation layer 101. The rubbing orientation of the alignment film overcomes the problem of light leakage at the portions on both sides of the data line 1, so that the brightness and chromaticity of the thin film transistor display device are uniform, and the display quality is improved.

As for the positional relationship between other structures and structures of the thin film transistor array substrate, it can be set and adjusted according to actual needs, such as the positional relationship of the thin film transistors of the pixel electrode; the gate electrode, the source electrode, the drain electrode and the active layer pattern. The positional relationship can be set according to the type of the thin film transistor.

The above is only an exemplary embodiment of the present invention, and is not intended to limit the scope of the present invention. The scope of the present invention is defined by the appended claims.

Claims

A display substrate comprising a substrate and a first signal line disposed on the substrate, the first signal line extending in a first direction, wherein at least a portion of the first signal line comprises at least two layers stacked a conductive line; in a direction perpendicular to the first direction, a width of the conductive line closest to the substrate is greater than a width of the other conductive line, and an orthographic projection of the conductive line closest to the substrate on the substrate The long side extending in one direction is located outside the long side of the positive projection of the other conductive line on the substrate extending in the first direction.
The display substrate according to claim 1, wherein, for any two adjacent conductive lines, a width of the conductive line adjacent to the substrate is greater than a width of the other conductive line, and a conductive line adjacent to the substrate is The long side of the orthographic projection on the substrate extending in the first direction is located outside the long side of the orthogonal projection of the other conductive line on the substrate extending in the first direction.
The display substrate according to claim 1, wherein the at least two layers of conductive lines have the same thickness in a direction perpendicular to the substrate.
The display substrate according to any one of claims 1 to 3, wherein at least a portion of the first signal line is composed of a first conductive line and a second conductive line, the first conductive line being opposite to the second conductive line The line is closer to the substrate, the first conductive line is made of Al, and the second conductive line is made of Mo.
The display substrate according to any one of claims 1 to 3, wherein the display substrate is a thin film transistor array substrate, and the first signal line is a data line;

The display substrate further includes an alignment film whose orientation direction is perpendicular to the first direction.
A display device comprising the display substrate of any of claims 1-5.
A method of manufacturing a display substrate according to any one of claims 1 to 5, comprising:

Forming a first signal line on a substrate;

Forming an alignment film on a side of the first signal line facing away from the substrate, the first signal line extending along a first direction, wherein the step of forming the first signal line comprises:

Forming at least two layers of conductive lines stacked; in a direction perpendicular to the first direction, a width of the conductive line closest to the substrate is greater than a width of the other conductive lines, and a conductive line closest to the substrate is on the substrate The long side of the upper orthographic projection extending in the first direction is located outside the first side of the long side of the orthographic projection of the other conductive line on the substrate.
The manufacturing method according to claim 7, wherein the forming the first signal line comprises:

Forming at least two conductive layers in sequence, each conductive layer being used to form a conductive line of the first signal line;

Forming a photoresist on the at least two conductive layers, exposing the photoresist, developing a photoresist non-retained region, and a photoresist retention region, wherein the photoresist retention region corresponds to at least the a region where the first signal line is located, the photoresist retention region includes a first remaining region of the photoresist and a second remaining region of the photoresist, wherein a thickness of the photoresist of the first remaining region of the photoresist is less than a thickness of the photoresist in the second remaining region of the photoresist, the first remaining region of the photoresist being located at an outermost periphery of the photoresist retention region in a direction perpendicular to the first direction;

Removing the at least two conductive layers of the photoresist non-retained region;

Removing the photoresist of the first remaining region of the photoresist by an ashing process, removing the conductive layer other than the conductive layer closest to the substrate of the first remaining region of the photoresist so as to be perpendicular to the first direction In the direction, the width of the conductive line closest to the substrate is greater than the width of the other conductive lines, and the long side of the orthographic projection of the conductive line closest to the substrate extending in the first direction on the substrate is located at other conductive lines. The outer side of the long side extending in the first direction of the orthographic projection on the substrate.
The manufacturing method according to claim 8, wherein the first signal line is composed of a first conductive line and a second conductive line, and the step of forming the first signal line comprises:

Forming a first conductive layer and a second conductive layer in sequence;

Forming a photoresist on the second conductive layer, exposing the photoresist, developing a photoresist non-retained region, and a photoresist retention region, wherein the photoresist retention region at least corresponds to the first a region where a signal line is located, the photoresist retention region includes a photoresist portion remaining region and a photoresist completely remaining region, wherein the photoresist portion retention region is located in a direction perpendicular to the first direction The photoresist completely retains the periphery of the area;

Removing the first conductive layer and the second conductive layer of the photoresist non-retained region, the first conductive line is formed by the first conductive layer, and a transition layer is formed by the second conductive layer;

Removing the photoresist of the remaining portion of the photoresist by an ashing process, and removing the second conductive layer of the remaining portion of the photoresist portion;

The photoresist in the completely remaining region of the photoresist is stripped, and the second conductive line is formed by the transition layer.
The fabricating method according to claim 9, wherein the first conductive layer and the second conductive layer of the photoresist non-retained region are removed by a wet etching process;

The second conductive layer of the remaining portion of the photoresist portion is removed by a dry etching process.