CN112464710B

CN112464710B - Sensing element substrate

Info

Publication number: CN112464710B
Application number: CN202011118143.4A
Authority: CN
Inventors: 陈信学; 苏志中; 陈亦伟
Original assignee: AU Optronics Corp
Current assignee: AU Optronics Corp
Priority date: 2019-11-05
Filing date: 2020-10-19
Publication date: 2023-06-06
Anticipated expiration: 2040-10-19
Also published as: CN112464710A

Abstract

The invention discloses a sensing element substrate which comprises a substrate, an active element, a photosensitive unit and a light collimation structure. The active device is located on the substrate and includes a drain. The photosensitive unit is positioned on the substrate and is electrically connected with the active element. The light collimation structure is positioned between the substrate and the photosensitive unit. The orthographic projection of the light collimation structure on the substrate falls within the orthographic projection of the photosensitive unit on the substrate, and at least one part of the light collimation structure and the drain electrode or the grid electrode belong to the same film layer.

Description

Sensing element substrate

Technical Field

The disclosure relates to a sensing element substrate.

Background

In recent years, electronic devices often have sensing elements to extend their functions, for example, the electronic devices may have fingerprint sensing elements to be able to be used as credentials for protecting the information security of the electronic devices. The fingerprint sensing device is usually fabricated on the pixel array substrate, but this may lead to a problem of reduced pixel aperture ratio. In order to increase the aperture ratio, one of the solutions is to manufacture the fingerprint sensing device on the opposite substrate, but an additional light control film layer is required to be attached to increase the sensitivity of the fingerprint sensing device. However, this not only increases the manufacturing cost and the thickness of the panel, but also causes a problem of poor viewing angle. Therefore, a method for solving the above problems is needed.

Disclosure of Invention

The disclosure provides a sensing element substrate which has the advantages of light weight and good fingerprint resolution.

The sensing element substrate comprises a substrate, an active element, a photosensitive unit and a light collimation structure. The active device is located on the substrate and includes a drain. The photosensitive unit is positioned on the substrate and is electrically connected with the active element. The light collimation structure is positioned between the substrate and the photosensitive unit. The orthographic projection of the light collimation structure on the substrate falls in the orthographic projection of the photosensitive unit on the substrate, the drain electrode and the light collimation structure belong to the same film layer, and the material of the drain electrode is the same as that of the light collimation structure.

In an embodiment of the disclosure, the sensing device substrate further includes an interlayer dielectric layer. The interlayer dielectric layer is positioned between the substrate and the photosensitive unit and is provided with a plurality of through holes. The light collimation structure comprises a plurality of extension parts, each extension part is positioned in each through hole of the interlayer dielectric layer, the extension direction of the extension parts is substantially parallel to the normal direction of the substrate, and the interval between the extension parts is 2 micrometers to 10 micrometers.

In an embodiment of the disclosure, the sensing device substrate further includes a control line. The control line is located on the substrate and electrically connected with the active element, and the extension part is substantially perpendicular to the control line.

In an embodiment of the disclosure, an aspect ratio of each of the extending portions is 0.1 to 6.

In an embodiment of the disclosure, the extension portion further includes a plurality of first sub-extension portions and a plurality of second sub-extension portions. The second sub-extension parts and the first sub-extension parts are arranged in a staggered mode, so that the second sub-extension parts and the first sub-extension parts form a net pattern, the number of the first sub-extension parts is more than 2, and the number of the second sub-extension parts is more than 2.

In an embodiment of the disclosure, the sensing device substrate further includes a control line. The control line is located on the substrate and electrically connected with the active element, and the extending direction of the second sub-extending part is staggered with the control line.

In an embodiment of the disclosure, the sensing device substrate further includes a control line. The control line is located on the substrate and electrically connected with the active element, and the second sub-extension part is substantially parallel to the control line.

Based on the above, in the sensing element substrate disclosed in the present disclosure, by disposing the light collimating structure between the substrate and the photosensitive unit, the path of the light reflected by the peaks and the troughs of the fingerprint traveling toward the photosensitive unit can be more collimated, and at least a portion of the light collimating structure and the drain electrode or the gate electrode belong to the same film layer, and since the light collimating film layer does not need to be attached to the display device, the display device can have the advantages of both light and thin and good fingerprint resolution. The front projection of the light collimation structure on the substrate falls into the front projection of the photosensitive unit on the substrate, so that the aperture ratio or the visual angle of the pixel array substrate is not affected.

The sensing element substrate comprises a substrate, an active element, a photosensitive unit and a light collimation structure. The active device is located on the substrate and comprises a gate and a drain. The photosensitive unit is positioned on the substrate and is electrically connected with the active element. The light collimation structure is positioned between the substrate and the photosensitive unit. The light collimation structure is arranged in the orthographic projection of the substrate in the orthographic projection of the photosensitive unit in the substrate, the light collimation structure comprises a plurality of extending parts, the extending directions of the extending parts are substantially parallel to the normal direction of the substrate, each extending part is provided with a lower part and an upper part which are connected, the lower part and the grid electrode belong to the same film layer, the lower part is made of the same material as the grid electrode, the upper part and the drain electrode belong to the same film layer, and the upper part is made of the same material as the drain electrode.

In an embodiment of the disclosure, a lower portion of each of the extending portions contacts the substrate, and an aspect ratio of each of the extending portions is 0.1 to 6.

In an embodiment of the disclosure, the sensing device substrate further includes an interlayer dielectric layer. The interlayer dielectric layer is positioned between the substrate and the photosensitive unit and is provided with a plurality of through holes. The light collimating structure further comprises a plurality of island portions located above the upper portions of the extension portions, the upper portions and the lower portions of the extension portions being located in the through holes of the interlayer dielectric layer, and the island portions being located outside the through holes.

Based on the above, in the sensing element substrate disclosed in the present disclosure, by disposing the light collimating structure between the substrate and the light sensing unit, the path of the light reflected by the wave crest and the wave trough of the fingerprint traveling toward the light sensing unit can be more collimated, the lower portion of the gate and the light collimating structure belong to the same film layer, the material of the gate and the material of the lower portion of the light collimating structure are the same, the upper portion of the drain and the light collimating structure belong to the same film layer, and the material of the drain and the material of the upper portion of the light collimating structure are the same, and since there is no need to attach an additional light collimating film layer to the display device, the display device can have the advantages of both light weight and good fingerprint resolution. The front projection of the light collimation structure on the substrate falls into the front projection of the photosensitive unit on the substrate, so that the aperture ratio or the visual angle of the pixel array substrate is not affected.

Drawings

Various aspects of the present disclosure can be appreciated upon reading the following detailed description in conjunction with the corresponding drawings. It should be noted that the various features of the drawings are not drawn to scale according to standard practices in the art. In fact, the dimensions of the features may be arbitrarily increased or reduced for clarity of discussion.

Fig. 1 is a schematic cross-sectional view of a display device according to an embodiment of the disclosure.

FIG. 2 is a schematic top view of the sensing element substrate of FIG. 1.

Fig. 3A is a schematic cross-sectional view along section line A-A' of fig. 2.

Fig. 3B is a schematic cross-sectional view of the section line B-B' of fig. 2.

Fig. 3C is a schematic cross-sectional view of the section line C-C' of fig. 2.

Fig. 3D is a schematic cross-sectional view according to the cross-section D-D' of fig. 2.

FIG. 4 is a schematic cross-sectional view of a sensing device substrate according to another embodiment of the disclosure.

FIG. 5A is a schematic top view of a sensing device substrate according to another embodiment of the disclosure.

FIG. 5B is a top view of a sensing device substrate according to another embodiment of the disclosure.

FIG. 6A is a schematic cross-sectional view of a sensing device substrate according to another embodiment of the disclosure.

FIG. 6B is a cross-sectional view of a sensing device substrate according to another embodiment of the disclosure.

FIG. 7A is a schematic cross-sectional view of a sensing device substrate according to another embodiment of the disclosure.

FIG. 7B is a cross-sectional view of a sensing device substrate according to another embodiment of the disclosure.

Wherein, the reference numerals:

10 display device

100 sense element substrate

100a sensing element substrate

100b sensing element substrate

100c, 100d, 100e sensing element substrate

102 photosensitive unit

102A first electrode layer

102B second electrode layer

102S sensing layer

104 light collimation structure

104A extension

104B island

106 buffer layer

108 insulating layer

110 interlayer dielectric layer

112 insulating layer

114 passivation layer

200 pixel array substrate

300 display dielectric layer

400 backlight module

A1 angle

A-A' section line

B-B' section line

BM black matrix

C-C' section line

CF color filter pattern

CH semiconductor channel layer

CL control line

D drain electrode

D1 first direction

D2 second direction

D-D' profile

DL data line

E1 first sub-extension

E2 second sub-extension

F finger

G grid electrode

H1 through hole

L1 ray

OC cover plate

P1 lower part

P2 upper part

S source electrode

S1 spacing

SL signal line

SM light shielding layer

SUB substrate

T active element

TH1, TH2, TH3, TH4 contact holes

H1, H2, H3 through holes

Detailed Description

In order to make the above features and advantages of the present invention more comprehensible, embodiments accompanied with figures are described in detail below.

Fig. 1 is a schematic cross-sectional view of a display device 10 according to an embodiment of the disclosure. The display device 10 includes a sensing element substrate 100, a pixel array substrate 200, a display medium layer 300, and a backlight module 400. The display medium layer 300 is located between the pixel array substrate 200 and the sensing element substrate 100, and the backlight module 400 is disposed below the pixel array substrate 200, in other words, the pixel array substrate 200 is located between the sensing element substrate 100 and the backlight module 400. Fig. 1 omits to illustrate a part of components of the sensing element substrate 100 and components of the pixel array substrate 200. Fig. 2 is a schematic top view of the sensing device substrate 100 of fig. 1, fig. 3A is a schematic cross-sectional view along a line A-A 'of fig. 2, fig. 3B is a schematic cross-sectional view along a line B-B' of fig. 2, fig. 3C is a schematic cross-sectional view along a line C-C 'of fig. 2, and fig. 3D is a schematic cross-sectional view along a line D-D' of fig. 2. Referring to fig. 1, 2 and 3A, the sensing device substrate 100 includes a substrate SUB, and an active device T, a photosensitive unit 102 and a light collimating structure 104 disposed on the substrate SUB. In one embodiment, the sensing device substrate 100 further includes a light shielding layer SM, a buffer layer 106, an insulating layer 108, and an interlayer dielectric layer 110. The light shielding layer SM is disposed on the substrate SUB, and the material of the light shielding layer SM is, for example, metal, resin, graphite or other applicable materials. The light shielding layer SM can be used to avoid the problem of light leakage generated by the active device T. The buffer layer 106 is located above the light shielding layer SM and above the substrate SUB. The substrate SUB is made of glass, quartz or an organic polymer, for example.

The active device T is disposed on the insulating layer 108, and the active device T includes a gate G, a source S, a drain D, and a semiconductor channel layer CH. The semiconductor channel layer CH is disposed on the insulating layer 108, the front projection of the gate electrode G on the substrate SUB overlaps the front projection of the semiconductor channel layer CH on the substrate SUB, and the insulating layer 108 is sandwiched between the gate electrode G and the semiconductor channel layer CH.

In this embodiment, the sensing device substrate 100 further includes a data line DL, a control line CL and a signal line SL on the substrate SUB. For convenience of illustration, fig. 2 shows a first direction D1 and a second direction D2, and the first direction D1 and the second direction D2 are different, for example, the first direction D1 and the second direction D2 are the longitudinal direction and the transverse direction of fig. 1, respectively, and are in an orthogonal relationship with each other. In the present embodiment, the control line CL extends along the second direction D2, and the data line DL and the signal line SL extend along the first direction D1. The gate G of the active device T is electrically connected to the control line CL. In this embodiment, the gate G and the control line CL belong to the same layer, i.e. are patterned from the same material layer. That is, the material of the gate electrode G is the same as that of the control line CL. The interlayer dielectric layer 110 is disposed on the insulating layer 108, the source S and the drain D are disposed on the insulating layer 108, and the source S is electrically connected to the data line DL. In this embodiment, the source S, the drain D, the data line DL, and the signal line SL belong to the same layer, i.e. are patterned from the same material layer. That is, the source electrode S, the drain electrode D, the data line DL, and the signal line SL are made of the same material. The source S and the drain D are electrically connected to the semiconductor channel layer CH through contact holes TH1 and TH2, respectively, and the contact holes TH1 and TH2 are located in the insulating layer 108 and the interlayer dielectric layer 110, for example. The active device T is illustrated by a top gate thin film transistor, but the disclosure is not limited thereto. In other embodiments, the active device T may be a bottom gate thin film transistor, or other suitable thin film transistor. In the present embodiment, the materials of the gate electrode G, the control line CL, the data line DL, the signal line SL, the drain electrode D, and the source electrode S are metal materials based on the consideration of conductivity. However, the present invention is not limited thereto, and according to other embodiments, other conductive materials may be used for the gate electrode G, the control line CL, the data line DL, the signal line SL, the drain electrode D, and the source electrode S, for example: alloys, nitrides of metallic materials, oxides of metallic materials, oxynitrides of metallic materials, or other suitable materials, or stacked layers of metallic materials and other conductive materials.

The sensing device substrate 100 further includes a black matrix BM, a color filter pattern CF, and a cover plate OC. The black matrix BM is disposed on the active device T, and the color filter pattern CF is disposed on the black matrix BM, and includes, for example, a red filter pattern, a green filter pattern and a blue filter pattern. The color filter pattern CF is disposed corresponding to the opening region of the pixel array substrate 200. The black matrix BM is provided corresponding to the control line CL, the data line DL, the signal line SL, the active device T, and the photosensitive cell 102, for example. The light collimating structure 104 is located between the substrate SUB and the photosensitive unit 102. In the present embodiment, the front projection of the light collimating structure 104 on the substrate SUB falls within the front projection of the photosensitive unit 102 on the substrate SUB, so that the aperture ratio or the viewing angle of the pixel array substrate 200 is not affected. The cover OC is disposed opposite to the substrate SUB, and the cover OC is made of, for example, a flexible substrate (e.g., a plastic substrate) or a rigid substrate (e.g., a glass substrate or a quartz substrate). In this embodiment, the material of the light collimating structure 104 is a metallic material. However, the invention is not limited thereto, and according to other embodiments, other conductive materials may be used for the material of the light collimating structure 104, such as: alloys, nitrides of metallic materials, oxides of metallic materials, oxynitrides of metallic materials, or other suitable materials, or stacked layers of metallic materials and other conductive materials.

The sensing element substrate 100 in the present embodiment is assembled with the cover plate OC facing the pixel array substrate 200, that is, the cover plate OC is located between the pixel array substrate 200 and the substrate SUB. When the finger F touches or approaches the substrate SUB of the sensing device substrate 100, for example, after the finger F touches the substrate SUB of the sensing device substrate 100, the light L1 emitted by the backlight module 400 irradiates the peaks and the valleys of the fingerprint, the peaks and the valleys reflect the light beams with different intensities, so that the plurality of photosensitive units 102 corresponding to the peaks and the valleys respectively receive the reflected light beams with different intensities, and the sensing device substrate 100 can obtain the fingerprint image of the user. The light collimating structure 104 can collimate the light reflected by the peaks and valleys of the fingerprint toward the path of travel of the photosensitive unit 102. Thus, the fingerprint resolution of the sensor substrate 100 can be improved. In this embodiment, the drain D, the source S and the light collimating structure 104 belong to the same film layer, i.e. are patterned from the same material layer. That is, the material of the light collimating structure 104 is the same as that of the drain electrode D and the source electrode S. For example, in an embodiment in which the material of the drain D and the source S includes a metal material, the light collimating structure 104 also includes a metal material. Since no additional light collimating film layer is required to be attached to the display device 10, the display device 10 has the advantages of light and thin structure and good fingerprint resolution.

The photosensitive unit 102 is located on the buffer layer 106. The photosensitive unit 102 includes a first electrode layer 102A, a second electrode layer 102B opposite to the first electrode layer 102A, and a sensing layer 102S interposed between the first electrode layer 102A and the second electrode layer 102B, the second electrode layer 102B being closer to the pixel array substrate 200 than the first electrode layer 102A. The first electrode layer 102A is electrically connected to the signal line SL. In this embodiment, referring to fig. 3B, the first electrode layer 102A is electrically connected to the signal line SL through the contact hole TH 3. The material of the first electrode layer 102A includes a transparent conductive material, such as indium tin oxide, indium zinc oxide, aluminum tin oxide, aluminum zinc oxide, indium gallium zinc oxide, or other suitable oxide, or a stacked layer of at least two of the foregoing. The material of the sensing layer 102S is, for example, silicon-rich oxide (SRO) or other suitable materials.

The photosensitive unit 102 is electrically connected to the active device T, for example, the second electrode layer 102B is electrically connected to the active device T. In this embodiment, the second electrode layer 102B is electrically connected to the active device T through the contact hole TH4, and the contact hole TH4 is located in the insulating layer 108, for example. The material of the second electrode layer 102B is, for example, molybdenum, aluminum, titanium, copper, gold, silver, or other conductive materials or a stack of two or more of the above materials.

In the present embodiment, the sensing device substrate 100 further includes an insulating layer 112 and a passivation layer 114, the insulating layer 112 covers the active device T and the light collimating structure 104, the passivation layer 114 is located on the insulating layer 112, and the passivation layer 114 covers the photosensitive unit 102 (e.g. the first electrode layer 102A and the second electrode layer 102B).

The interlayer dielectric layer 110 is disposed between the substrate SUB and the photosensitive unit 102 and has a plurality of through holes H1. The light collimating structure 104 includes a plurality of extension portions 104A, wherein each extension portion 104A is located in each through hole H1 of the interlayer dielectric layer 110, and the through holes H1 and TH2 of the interlayer dielectric layer 110 are formed by, for example, forming a photoresist layer (not shown) on the interlayer dielectric layer 110, patterning the photoresist layer using a photomask to form a patterned photoresist layer, etching the interlayer dielectric layer 110 to form the through holes H1 and the contact holes TH1 and TH2, and removing the patterned photoresist layer. Since the via hole H1 and the contact holes TH1 and TH2 are formed by the same mask, no additional mask is required to manufacture the via hole H1, thereby contributing to reducing the manufacturing cost and no retesting of the etching parameters of the interlayer dielectric layer 110 is required. In this embodiment, the light collimating structure 104 extends to the through hole H2 of the insulating layer 108 to contact the top surface of the buffer layer 106.

The extending direction of the extending portions 104A is substantially parallel to the normal direction of the substrate SUB plate, and the spacing S1 between the extending portions 104A is 2 micrometers to 10 micrometers, where the spacing S1 is small enough to enable the light beam to travel between the adjacent extending portions 104A at a small angle, so as to control the light beam reflected by the peaks and valleys of the fingerprint to be more collimated towards the path of the light sensing unit 102. In this embodiment, the light collimating structure 104 further includes a plurality of islands 104B above the extending portion 104A, and the islands 104B are located outside the through holes H1.

In the present embodiment, the cross section of the extension 104A along the section line D-D' is sheet-shaped (see fig. 3D). In the case of viewing from the top view, the extension portion 104A is in a strip shape extending along the first direction D1, so that the light collimating structure 104 has the advantage of simple manufacturing process, for example, the extension portion 104A is substantially parallel to the data line DL and the signal line SL. In one embodiment, the number of the extension portions 104A is greater than 2. The aspect ratio of each extension 104A is 0.1 to 6, and the aspect ratio is large enough to further enhance the light collimation effect. In this embodiment, the light collimating structure 104 is located on the buffer layer 106. In other embodiments, the light collimating structure 104 may extend into the through hole H3 (see fig. 4) in the buffer layer 106 and contact the substrate SUB.

FIG. 5A is a schematic top view of a sensing device substrate 100a according to another embodiment of the disclosure. The main difference between the sensing device substrate 100a of fig. 5A and the sensing device substrate 100 of fig. 2 is that: the extension portion 104A further includes a plurality of first sub-extension portions E1 and a plurality of second sub-extension portions E2. In an embodiment, the second sub-extensions E2 and the first sub-extensions E1 are staggered, so that the second sub-extensions E2 and the first sub-extensions E1 form a mesh pattern, which can further enhance the light collimation effect. And the number of the first sub-extension E1 is greater than 2, and the number of the second sub-extension E2 is greater than 2. In the present embodiment, the second sub-extension E2 is in a sheet shape extending along the second direction D2, for example, the second sub-extension E2 is substantially parallel to the control line CL. In other embodiments, the second sub-extension E2 and the first sub-extension E1 form a non-right angle A1 when viewing the second sub-extension E2 from the top view (see fig. 5B).

FIG. 6A is a schematic cross-sectional view of a sensing device substrate 100b according to another embodiment of the disclosure. The main difference between the sensing device substrate 100B of fig. 6A and the sensing device substrate 100 of fig. 3B is that: each extension 104A has a lower portion P1 and an upper portion P2 connected to each other, and the lower portion P1 and the gate G belong to the same layer, i.e. are patterned from the same material layer. That is, the material of the lower portion P1 is the same as that of the gate electrode G. For example, in the embodiment where the material of the gate G includes a metal material, the lower portion P1 also includes a metal material. The upper portion P2, the drain D and the source S belong to the same layer, i.e. are patterned from the same material layer. That is, the material of the upper portion P2 is the same as that of the drain D and the source S. For example, in the embodiment where the material of the drain D and the source S includes a metal material, the upper portion P2 also includes a metal material. Since no additional light collimating film (not shown) is required to be attached to the display device 10, the display device 10 has the advantages of light and thin structure and good fingerprint resolution. The lower portion P1 of each extension 104A contacts the substrate SUB, and the combined aspect ratio of the upper portion P2 and the lower portion P1 of each extension 104A is 0.1 to 6.

FIG. 6B is a schematic cross-sectional view of a sensing device substrate 100c according to another embodiment of the disclosure. The main difference between the sensing device substrate 100c of the present embodiment and the sensing device substrate 100b of fig. 6A is that: the lower portion P1 of each extension 104A extends to the through hole H2 of the insulating layer 108 to contact the top surface of the buffer layer 106.

FIG. 7A is a schematic cross-sectional view of a sensing device substrate 100d according to another embodiment of the disclosure. The main difference between the sensing device substrate 100d of the present embodiment and the sensing device substrate 100 of fig. 3B is that: the light collimating structure 104 and the gate G belong to the same film layer, i.e. are patterned from the same material layer. That is, the material of the light collimating structure 104 is the same as the material of the gate electrode G. For example, in an embodiment in which the material of the gate G includes a metal material, the light collimating structure 104 also includes a metal material. Since no additional light collimating film (not shown) is required to be attached to the display device 10, the display device 10 has the advantages of light and thin structure and good fingerprint resolution. In this embodiment, the light collimating structure 104 extends to the through hole H2 of the insulating layer 108 to contact the top surface of the buffer layer 106.

FIG. 7B is a schematic cross-sectional view of a sensing device substrate 100e according to another embodiment of the disclosure. The main difference between the sensing device substrate 100e of the present embodiment and the sensing device substrate 100d of fig. 7A is that: the light collimating structure 104 extends in the through hole H3 in the buffer layer 106 and contacts the substrate SUB.

In summary, the sensing device substrate of the embodiment of the disclosure can make the path of the light reflected by the peaks and the troughs of the fingerprint traveling toward the photosensitive unit more collimated by disposing the light collimating structure between the substrate and the photosensitive unit, and the gate or the drain and at least a portion of the light collimating structure belong to the same film layer, and the material of the gate or the drain and the material of at least a portion of the light collimating structure are the same, so that the display device can have the advantages of both light and thin and good fingerprint resolution because no additional light collimating film layer is required to be attached to the display device. The front projection of the light collimation structure on the substrate falls into the front projection of the photosensitive unit on the substrate, so that the aperture ratio or the visual angle of the pixel array substrate is not affected.

Of course, the present invention is capable of other various embodiments and its several details are capable of modification and variation in light of the present invention, as will be apparent to those skilled in the art, without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A sensing element substrate, comprising:

a substrate;

an active device on the substrate, wherein the active device comprises a drain electrode;

the photosensitive unit is positioned on the substrate and is electrically connected with the active element; and

the light collimation structure is positioned between the substrate and the photosensitive unit, wherein the orthographic projection of the light collimation structure on the substrate falls in the orthographic projection of the photosensitive unit on the substrate, the drain electrode and the light collimation structure belong to the same film layer, and the material of the drain electrode is the same as that of the light collimation structure.

2. The sensing device substrate of claim 1, further comprising:

the light collimation structure comprises a substrate, a photosensitive unit, an interlayer dielectric layer, a plurality of light collimation layers and a light absorption layer, wherein the interlayer dielectric layer is positioned between the substrate and the photosensitive unit and is provided with a plurality of through holes, each extending part is positioned in each through hole of the interlayer dielectric layer, the extending direction of each extending part is substantially parallel to a normal direction of the substrate, and the distance between the extending parts is 2 micrometers to 10 micrometers.

3. The sensing device substrate of claim 2, further comprising:

and the control line is positioned on the substrate and is electrically connected with the active element, wherein the extension parts are substantially perpendicular to the control line.

4. The sensor device substrate of claim 2, wherein each of the extensions has an aspect ratio of 0.1 to 6.

5. The sensing device substrate of claim 2, wherein the extensions further comprise:

a plurality of first sub-extensions; and

the second sub-extension parts and the first sub-extension parts are arranged in a staggered mode, so that the second sub-extension parts and the first sub-extension parts form a net pattern, the number of the first sub-extension parts is more than 2, and the number of the second sub-extension parts is more than 2.

6. The sensing device substrate of claim 5, further comprising:

and the control line is positioned on the substrate and is electrically connected with the active element, wherein the extending directions of the second sub-extending parts are staggered with the control line.

7. The sensing device substrate of claim 5, further comprising:

and a control line on the substrate and electrically connected to the active device, wherein the second sub-extensions are substantially parallel to the control line.

8. A sensing element substrate, comprising:

a substrate;

an active device on the substrate, wherein the active device comprises a gate and a drain;

the light collimation structure is positioned between the substrate and the photosensitive unit, wherein the orthographic projection of the light collimation structure on the substrate falls within the orthographic projection of the photosensitive unit on the substrate, the light collimation structure comprises a plurality of extending parts, the extending directions of the extending parts are substantially parallel to a normal direction of the substrate, each extending part is provided with a lower part and an upper part which are connected, the lower part and the grid electrode belong to the same film layer, the lower part and the grid electrode are made of the same material, the upper part and the drain electrode belong to the same film layer, and the upper part and the drain electrode are made of the same material.

9. The sensor device substrate of claim 8, wherein the lower portion of each of the extensions contacts the substrate and the aspect ratio of each of the extensions is 0.1 to 6.

10. The sensing device substrate of claim 8, further comprising:

and an interlayer dielectric layer between the substrate and the photosensitive unit and having a plurality of through holes, wherein the light collimating structure further comprises a plurality of islands above the upper parts of the extending parts, the upper part and the lower part of each extending part are located in the through holes of the interlayer dielectric layer, and the islands are located outside the through holes.

11. A sensing element substrate, comprising:

a substrate;

the light collimation structure is positioned between the substrate and the photosensitive unit, wherein the orthographic projection of the light collimation structure on the substrate falls within the orthographic projection of the photosensitive unit on the substrate, the grid electrode and the light collimation structure belong to the same film layer, and the material of the grid electrode is the same as that of the light collimation structure.