WO2020207408A1 - 指纹识别传感器及其制备方法、以及显示装置 - Google Patents

指纹识别传感器及其制备方法、以及显示装置 Download PDF

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Publication number
WO2020207408A1
WO2020207408A1 PCT/CN2020/083760 CN2020083760W WO2020207408A1 WO 2020207408 A1 WO2020207408 A1 WO 2020207408A1 CN 2020083760 W CN2020083760 W CN 2020083760W WO 2020207408 A1 WO2020207408 A1 WO 2020207408A1
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Prior art keywords
base substrate
electrode
layer
photosensitive
thin film
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PCT/CN2020/083760
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English (en)
French (fr)
Inventor
李士佩
赵影
顾仁权
何伟
吴慧利
尹东升
徐胜
张立震
赵雪飞
贺芳
高宇鹏
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京东方科技集团股份有限公司
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Priority to US17/041,516 priority Critical patent/US11605239B2/en
Publication of WO2020207408A1 publication Critical patent/WO2020207408A1/zh

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    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V40/00—Recognition of biometric, human-related or animal-related patterns in image or video data
    • G06V40/10—Human or animal bodies, e.g. vehicle occupants or pedestrians; Body parts, e.g. hands
    • G06V40/12—Fingerprints or palmprints
    • G06V40/13—Sensors therefor
    • G06V40/1318—Sensors therefor using electro-optical elements or layers, e.g. electroluminescent sensing
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14678—Contact-type imagers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14601—Structural or functional details thereof
    • H01L27/14609—Pixel-elements with integrated switching, control, storage or amplification elements
    • H01L27/1461—Pixel-elements with integrated switching, control, storage or amplification elements characterised by the photosensitive area
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14601—Structural or functional details thereof
    • H01L27/14609—Pixel-elements with integrated switching, control, storage or amplification elements
    • H01L27/14612—Pixel-elements with integrated switching, control, storage or amplification elements involving a transistor
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14601—Structural or functional details thereof
    • H01L27/14638—Structures specially adapted for transferring the charges across the imager perpendicular to the imaging plane
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14683—Processes or apparatus peculiar to the manufacture or treatment of these devices or parts thereof

Definitions

  • the embodiments of the present disclosure relate to a fingerprint recognition sensor, a preparation method thereof, and a display device.
  • OLED Organic Light-Emitting Diode
  • the embodiments of the present disclosure provide a fingerprint recognition sensor, a preparation method thereof, and a display device, so as to solve the problem that the photosensitive device and the thin film transistor in the existing fingerprint recognition sensor are arranged adjacent to each other, so that the installation space of the photosensitive device is small, resulting in the fingerprint recognition sensor The effective photosensitive area is small and the fingerprint recognition accuracy is low.
  • At least one embodiment of the present disclosure provides a fingerprint recognition sensor, which includes: a base substrate; a thin film transistor located on one side of the base substrate; and a photosensitive device located on a side of the base substrate away from the thin film transistor
  • the thin film transistor, the base substrate, and the photosensitive device are sequentially stacked in a thickness direction perpendicular to the base substrate, and the base substrate includes in the thickness direction perpendicular to the base substrate.
  • the photosensitive device is connected to the thin film transistor through the conductive structure.
  • the conductive structure includes a first conductive substructure and a second conductive substructure that are separated, and the first conductive substructure and the second conductive substructure are
  • the base substrate passes through the base substrate in the thickness direction;
  • the photosensitive device includes: a first electrode located on the first surface of the base substrate; and the first electrode is located away from the substrate A photosensitive layer on one side of the substrate; and a second electrode on the side of the photosensitive layer away from the first electrode, the first electrode is connected to the first conductive substructure, and the second electrode is configured Is electrically connected to the second conductive substructure.
  • the photosensitive device includes a photosensitive layer
  • the thin film transistor includes an active layer
  • the orthographic projection of the photosensitive layer on the base substrate is consistent with the The orthographic projections of the source layer on the base substrate overlap.
  • the orthographic projection of the photosensitive layer on the base substrate covers the orthographic projection of the active layer on the base substrate.
  • the photosensitive device further includes: a protective layer covering the first electrode, the photosensitive layer, the second electrode and the second electrode of the base substrate A surface; and a first lap electrode located on the side of the protective layer away from the photosensitive layer, the protective layer including a first via hole and a second via hole, the first lap electrode passes through the protection
  • the first via hole in the layer is connected to the second electrode, and the first bonding electrode is connected to the second conductive substructure through the second via hole in the protective layer.
  • the fingerprint recognition sensor provided by an embodiment of the present disclosure further includes: a third electrode located on a second surface of the base substrate opposite to the first surface and connected to the second conductive substructure The third electrode is configured to input a working voltage to the photosensitive device through the second conductive substructure and the first bonding electrode.
  • the material of the first bonding electrode is a transparent electrode material.
  • the thin film transistor further includes: a gate located on the surface of the base substrate on a side away from the photosensitive device; and a gate insulating layer located on the surface of the substrate.
  • the gate is away from the side of the base substrate and covers the gate; and the source and the drain,
  • the active layer is located on the side of the gate insulating layer away from the gate
  • the source and drain are located on the side of the gate insulating layer away from the active layer
  • the source The electrode and the drain electrode are respectively connected to the active layer
  • the gate insulating layer includes a third via hole
  • the source electrode or the drain electrode passes through the third via hole in the gate insulating layer.
  • the first conductive substructure of the base substrate is connected.
  • the fingerprint recognition sensor provided by an embodiment of the present disclosure further includes a passivation layer, which is located on a side of the source and the drain away from the active layer, and covers the source and the drain. , The active layer and the gate insulating layer.
  • At least one embodiment of the present disclosure further provides a method for preparing a fingerprint recognition sensor, which includes: providing a base substrate, the base substrate includes a base substrate that penetrates the base substrate in a thickness direction perpendicular to the base substrate A conductive structure; a thin film transistor is formed on one side of the base substrate; and a photosensitive device is formed on the side of the base substrate away from the thin film transistor, and the thin film transistor, the base substrate and the photosensitive device are along perpendicular to the The thickness direction of the base substrate is sequentially stacked and arranged, and the photosensitive device is connected to the thin film transistor through the conductive structure.
  • the conductive structure includes separate first conductive substructures and second conductive substructures, and the first conductive substructures and the second conductive substructures are
  • the base substrate passes through the base substrate in the thickness direction; forming the photosensitive device on the side of the base substrate away from the thin film transistor includes: forming a first electrode on the first surface of the base substrate; Forming a photosensitive layer on the side of the first electrode away from the base substrate; and forming a second electrode on the side of the photosensitive layer away from the first electrode, the first electrode and the first conductive element
  • the structure is connected, and the second electrode is configured to be electrically connected to the second conductive substructure.
  • forming the photosensitive device on the side of the base substrate away from the thin film transistor further includes: forming a protective layer on the side of the second electrode away from the photosensitive layer, The protective layer covers the first electrode, the photosensitive layer, the second electrode and the first surface of the base substrate; and a first lap electrode is formed on the side of the protective layer away from the photosensitive layer , The first lap electrode is located on the side of the protection layer away from the photosensitive layer.
  • the protection layer includes a first via hole and a second via hole, and the first lap electrode passes through the The first via hole is connected to the second electrode, and the first bonding electrode is connected to the second conductive substructure through the second via hole in the protective layer.
  • the preparation method provided in an embodiment of the present disclosure further includes: forming a third electrode on a second surface of the base substrate opposite to the first surface, and the third electrode is connected to the second surface.
  • the conductive substructure is connected; the third electrode is configured to input a working voltage to the photosensitive device through the second conductive substructure and the first bonding electrode.
  • forming a thin film transistor on one side of the base substrate includes: forming a gate on one side of the base substrate; A gate insulating layer is formed on the side, the gate insulating layer covers the gate; an active layer is formed on the side of the gate insulating layer away from the gate; and the active layer is away from the gate A source electrode and a drain electrode are formed on one side of the electrode insulating layer, the source electrode and the drain electrode are respectively connected to the active layer, the gate insulating layer includes a third via hole, the source electrode or the drain electrode The drain is connected to the first conductive substructure of the base substrate through a third via hole in the gate insulating layer.
  • the orthographic projection of the photosensitive layer on the base substrate overlaps the orthographic projection of the active layer on the base substrate.
  • the orthographic projection of the photosensitive layer on the base substrate covers the orthographic projection of the active layer on the base substrate.
  • the preparation method provided by an embodiment of the present disclosure further includes: forming a passivation layer on the side of the source and the drain away from the active layer, the passivation layer covering the source and the drain.
  • the drain, the active layer, and the gate insulating layer are formed on the side of the source and the drain away from the active layer.
  • At least one embodiment of the present disclosure further provides a display device including the fingerprint recognition sensor described in any one of the above.
  • Figure 1 shows a schematic cross-sectional view of a fingerprint recognition sensor
  • Figure 2 shows the I-V characteristic curve of a photosensitive device
  • Figure 3 shows the I-V characteristic curve of a thin film transistor
  • FIG. 4 shows a schematic cross-sectional view of a fingerprint identification sensor provided by an embodiment of the present invention
  • FIG. 5 shows a schematic cross-sectional view of another fingerprint identification sensor according to an embodiment of the present invention.
  • FIG. 6 shows the I-V characteristic curve of a photosensitive device in which both the first bonding electrode and the second electrode adopt transparent ITO according to an embodiment of the present invention
  • FIG. 7 shows a flowchart of a method for preparing a fingerprint identification sensor according to an embodiment of the present invention
  • FIG. 8 shows a schematic cross-sectional view of a base substrate provided by an embodiment of the present invention.
  • FIG. 9 shows a schematic cross-sectional view of a fingerprint recognition sensor after forming a gate and a third electrode according to an embodiment of the present invention.
  • FIG. 10 shows a schematic cross-sectional view of a fingerprint recognition sensor after forming a gate insulating layer and an active layer according to an embodiment of the present invention
  • FIG. 11 shows a schematic cross-sectional view of a fingerprint recognition sensor after forming a source electrode and a drain electrode according to an embodiment of the present invention
  • FIG. 12 shows a schematic cross-sectional view of a fingerprint recognition sensor after forming a passivation layer according to an embodiment of the present invention
  • Figure 13 shows a schematic cross-sectional view of a fingerprint recognition sensor forming a first electrode and a second overlapping electrode according to an embodiment of the present invention
  • FIG. 14 shows a schematic cross-sectional view of a fingerprint recognition sensor after forming a photosensitive layer and a second electrode according to an embodiment of the present invention.
  • FIG. 15 shows a schematic cross-sectional view of a fingerprint recognition sensor after forming a protective layer according to an embodiment of the present invention.
  • the fingerprint recognition sensor may include a photosensitive device and a thin film transistor arranged adjacently.
  • the arrangement of the thin film transistor needs to occupy a certain space, which will compress the installation space of the photosensitive device, while the fingerprint recognition sensor
  • the effective light-sensing area of the sensor comes from the photosensitive device, therefore, the installation space of the light-sensitive device is compressed, which will result in a smaller effective photosensitive area of the fingerprint recognition sensor, which in turn causes the photocurrent signal generated by the fingerprint recognition sensor to be weak, making fingerprint recognition accurate The degree is low.
  • FIG. 1 is a schematic cross-sectional view of a fingerprint recognition sensor.
  • the fingerprint recognition sensor includes a thin film transistor 1 and a photosensitive device 2; the thin film transistor 1 and the photosensitive device 2 can be arranged on the same side of the base substrate 3, and the two can be arranged adjacent to each other.
  • the thin film transistor 1 may include a gate 101 formed on a base substrate 3, a gate insulating layer 102 covering the gate 101, an active layer 103 formed on the gate insulating layer 102, The source 104 and the drain 105 of the active layer 103 are respectively connected, and the first passivation layer 106 covering the above-mentioned structures.
  • the photosensitive device 2 may include a first electrode 201 formed on the first passivation layer 106, a photosensitive layer 202 formed on the first electrode 201, a second electrode 203 formed on the photosensitive layer 202, and a protective layer covering the various structures described above.
  • Layer 204 a resin layer 205 covering the protective layer 204, a second passivation layer 206 covering the resin layer 205, a bonding electrode 207 (usually called Top Metal, top electrode) formed on the second passivation layer 206, and The buffer layer 208 covering the second passivation layer 206 and the overlap electrode 207.
  • a bonding electrode 207 usually called Top Metal, top electrode
  • the first electrode 201 is connected to the source 104 of the thin film transistor 1 through a via hole in the first passivation layer 106; the material of the second electrode 203 is usually ITO (Indium Tin Oxides, indium tin oxide); the bonding electrode 207 passes The resin layer 205 and the via holes in the resin layer 205 are connected to the second electrode 203; the bonding electrode 207 usually uses a conductive metal material.
  • the fingerprint recognition sensor shown in Figure 1 has at least the following problems:
  • the thin film transistor 1 and the photosensitive device 2 are arranged on the same side of the base substrate 3, and the two are arranged adjacent to each other. As a result, the arrangement of the thin film transistor 1 will compress the space of the photosensitive device 2, thereby reducing the photosensitive The effective photosensitive area of device 2.
  • the way that the thin film transistor 1 and the photosensitive device 2 are arranged adjacently has a greater impact on the effective photosensitive area of the photosensitive device 2.
  • the effective photosensitive area of the photosensitive device 2 will be sharply reduced by about 60%, and the amount of photocurrent signal will also be sharply reduced by about 60%, which will seriously affect Detection of photocurrent signal.
  • the overlap electrode 207 on the top of the photosensitive device 2 is usually made of conductive metal material, and the metal material has a low light transmittance. As a result, the part of the photosensitive device that is blocked by the overlap electrode 207 cannot be effectively sensitized.
  • the effective photosensitive area of the fingerprint recognition sensor is further reduced.
  • the overlap electrode 207 has a greater impact on the effective photosensitive area of the fingerprint recognition sensor, especially for display devices designed for high-density fingerprint recognition sensors. For example, when the display device includes 500 fingerprint recognition sensors per inch, the photosensitive device 2 is blocked.
  • the area ratio between the area of the overlap electrode and the effective photosensitive area of the fingerprint recognition sensor is about 17%. When the density of the fingerprint recognition sensor is higher, the area ratio will be higher.
  • the overlap electrode 207 It also has a greater impact on the effective photosensitive area of the fingerprint recognition sensor.
  • Fig. 2 shows the IV (current-voltage) characteristic curve of a photosensitive device 2; as shown in Fig. 2, the photosensitive device 2 can usually work under a negative bias of -4V (volt), when the photosensitive device 2 is input -4V Under the negative bias voltage, the photocurrent output by the photosensitive device 2 is shown in FIG. 2.
  • -4V volt
  • FIG. 2 The smaller the effective photosensitive area of the fingerprint identification sensor, the smaller the photocurrent of the photosensitive device 2, and the lower the accuracy of fingerprint identification.
  • Problem 3 The use of different materials for the second electrode 203 and the overlapping electrode 207 will cause the dark current of the photosensitive device 2 to be relatively large, resulting in a lower sensitivity of the photosensitive device 2.
  • the second electrode 203 and the bonding electrode 207 are made of different materials, the material matching between the two is lower and the noise is greater.
  • the dark current output by the photosensitive device 2 is shown in FIG. 2, where the greater the dark current of the photosensitive device 2, the lower the sensitivity of the photosensitive device 2 and the lower the accuracy of fingerprint recognition.
  • the active layer 103 of the thin film transistor 1 is easily conductive during the manufacturing process of the photosensitive device 2, thereby reducing the amount of photocurrent signal generated by the photosensitive device 2.
  • the active layer 103 of the thin film transistor 1 is easily interfered by hydrogen ions and becomes conductive to a certain extent, that is, the thin film transistor 1 is The closed state can still conduct more charge.
  • the photosensitive layer 202 of the photosensitive device 2 needs to be deposited and formed in a hydrogen ion-rich environment. Therefore, when the photosensitive layer 202 is deposited, the active layer 103 is easily conductive in the hydrogen ion environment, so that the thin film transistor 1 is turned off. At this time, part of the photogenerated charge stored in the photosensitive device 2 will be lost, thereby reducing the amount of photocurrent signal.
  • Figure 3 shows the IV curve of a thin film transistor 1, with reference to FIG. 3, when the gate voltage is lower than -10V, the thin film transistor 1 is turned off, but the drain current has a power of up to 10-11 magnitude, When the normal thin film transistor 1 is turned off, its drain current should be in the order of 10-15 . Therefore, the active layer 103 of the thin film transistor 1 corresponding to FIG. 3 has been conductorized to a certain extent, so that When the thin film transistor 1 is turned off, part of the photo-generated charges generated by the photosensitive device 2 will still be released through the active layer channel, thereby reducing the amount of photocurrent signal.
  • inventions of the present disclosure provide a fingerprint recognition sensor, a manufacturing method thereof, and a display device.
  • the fingerprint recognition sensor includes a base substrate; a thin film transistor located on one side of the base substrate; and a photosensitive device located on the side of the base substrate away from the thin film transistor.
  • the thin film transistor, the base substrate and the photosensitive device are perpendicular to the base substrate.
  • the thickness direction of the base plate is sequentially stacked and arranged, the base substrate includes a conductive structure that penetrates the base substrate in a thickness direction perpendicular to the base substrate, and the photosensitive device is connected to the thin film transistor through the conductive structure.
  • the fingerprint recognition sensor can avoid the space of the photosensitive device from being compressed by forming the photosensitive device and the thin film transistor on the two sides of the base substrate away from each other, and connecting them through the conductive structure in the base substrate, thereby making the photosensitive device more compact.
  • the effective photosensitive area can be increased, that is, the effective photosensitive area of the fingerprint identification sensor is increased, so that the photocurrent signal generated by the fingerprint identification sensor can be enhanced, thereby improving the accuracy of fingerprint identification.
  • FIG. 4 shows a schematic cross-sectional view of a fingerprint recognition sensor according to an embodiment of the present invention
  • the fingerprint recognition sensor includes a base substrate 10, a thin film transistor 20 (TFT) and a photosensitive device 30.
  • the thin film transistor 20, the base substrate 10, and the photosensitive device 30 are stacked in a direction perpendicular to the base substrate 10 (ie the thickness direction), that is, the thin film transistor 20 is located on one side of the base substrate 10, and the photosensitive device 30 is located on the substrate.
  • the side of the substrate 10 away from the thin film transistor 20.
  • the base substrate 10 may include a conductive structure 11 penetrating the base substrate 10 in the thickness direction of the base substrate 10, and the photosensitive device 30 may be connected to the thin film transistor 20 through the conductive structure 11 of the base substrate 10.
  • the thin film transistor 20 may be used to release the photo-generated charges generated by the photosensitive device 30.
  • the thin film transistor 20, the base substrate 10 and the photosensitive device 30 may be stacked in a direction perpendicular to the thickness of the base substrate 10, that is, the thin film transistor 20
  • the photosensitive device 30 and the photosensitive device 30 may be respectively disposed on two surfaces opposite to the base substrate 10, and the two may be electrically connected through the conductive structure 11 of the base substrate 10 to realize the control of the photosensitive device 30.
  • the conductive structure 11 of the base substrate 10 may include a separate first conductive substructure 111 and a second conductive substructure 112, and the first conductive substructure 111 and the second conductive substructure 112 are perpendicular to each other.
  • the base substrate 10 penetrates the base substrate 10 in the thickness direction.
  • the material of the conductive structure 11 may be a conductive material such as copper metal, which is not specifically limited in the embodiment of the present invention.
  • the photosensitive device 30 includes a first electrode 31 formed on the first surface S1 of the base substrate 10, a photosensitive layer 32 formed on the first electrode 31, a second electrode 33 formed on the photosensitive layer 32, and protection Layer 34, and the first bonding electrode 35.
  • the first electrode 31 is connected to the first conductive substructure 111; the protective layer 34 covers the first electrode 31, the photosensitive layer 32, the second electrode 33 and the first surface S1 of the base substrate 10; the first bonding electrode 35 is located
  • the protective layer 34 is away from the side of the base substrate 10; the first lap electrode 35 can be connected to the second electrode 33 through the first via 341 of the protective layer 34, and the first lap electrode 35 can pass through the second
  • the via 342 is connected to the second conductive substructure 112.
  • the photosensitive device 30 may be a PIN photodiode.
  • the photosensitive layer 32 may specifically include an N-type semiconductor layer, an intrinsic semiconductor layer, and a P-type semiconductor layer stacked along the thickness direction of the base substrate 10, and an N-type semiconductor layer It is arranged close to the first electrode 31.
  • the negative bias voltage required for the work can be applied to the photosensitive layer 32 through the second electrode 33, and then when photons with sufficient energy are incident on the photosensitive layer 32, the photosensitive layer can be excited 32 generates a photo-generated charge, thereby forming a photocurrent signal required for fingerprint recognition.
  • the first electrode 31 may be connected to the source or drain of the thin film transistor 20 through the first conductive substructure 111.
  • the display device can form a fingerprint image based on the photocurrent signal, and then perform fingerprint recognition. After that, the first electrode 31 connected to the photosensitive layer 32 can release the photogenerated charge through the thin film transistor 20.
  • the gate of the thin film transistor 20 can be in the off state, and the photo-generated charges generated by the photosensitive layer 32 can be introduced to the thin film through the first electrode 31, the first conductive substructure 111, and the source of the thin film transistor 20 in sequence.
  • the active layer of the transistor 20 is accumulated in the active layer.
  • the gate of the thin film transistor 20 is opened, the photo-generated charges can flow from the channel through the active layer to the drain of the thin film transistor 20, thereby being derived.
  • the first bonding electrode 35 may directly pass through the second via 342 and the second via 342 of the protective layer 34
  • the two conductive substructures 112 are connected.
  • the fingerprint recognition sensor may further include a second bonding electrode 01, wherein the second bonding electrode 01 may be provided in the same layer as the first electrode 31 of the photosensitive device 30, and the second The thickness of the bonding electrode 01 and the first electrode 31 may be the same, and the second bonding electrode 01 may be connected to the first bonding electrode 35 and the second conductive substructure 112 respectively. As shown in FIG.
  • the bottom of the second via 342 of the protection layer 34 is also the second bonding electrode 01. Accordingly, the first bonding electrode 35 can pass through the second via 342 and the second bonding of the protection layer 34
  • the electrode 01 is connected to the second conductive substructure 112.
  • the embodiment of the present invention does not specifically limit the connection between the first bonding electrode 35 and the second conductive substructure 112.
  • the area of the second electrode 33 may be smaller than the area of the photosensitive layer 32, so that the leakage current at the edge of the photosensitive device 30 can be reduced, and the sensitivity of the photosensitive device 30 can be improved.
  • the fingerprint recognition sensor may further include a third electrode 40 formed on the second surface S2 of the base substrate 10 opposite to the first surface S1 and connected to the second conductive surface.
  • the electronic structure 112 is connected.
  • the third electrode 40 may be configured to input an operating voltage, that is, a negative bias voltage, to the photosensitive device 30 through the second conductive substructure 112 and the first bonding electrode 35. That is, the operating voltage required by the photosensitive device 30 can be input to the third electrode 40, and the third electrode 40 can sequentially pass through the second conductive substructure 112, the first bonding electrode 35, and the second electrode 33 of the base substrate 10 , The operating voltage is input to the photosensitive layer 32.
  • the third electrode 40 and the gate electrode of the thin film transistor 20 can be arranged in the same layer, so that the third electrode 40 and the gate electrode of the thin film transistor 20 can be formed at the same time through one patterning process. In this way, the fingerprint identification sensor can be simplified. Preparation process.
  • the material of the first bonding electrode 35 may be a transparent electrode material, such as ITO, which is not specifically limited in the embodiment of the present invention. That is, the first overlap electrode 35 can be made of a transparent electrode material, so that the photosensitive device part that is blocked by the first overlap electrode 35 can be effectively sensitized, thereby increasing the effective photosensitive area of the fingerprint recognition sensor.
  • Fig. 6 shows the IV (current-voltage) characteristic curve of a photosensitive device 30 in which both the first bonding electrode 35 and the second electrode 33 adopt transparent ITO. Compared with Fig. 6 and Fig. 2, the metal is used for the bonding electrode. For photosensitive devices made of materials, the photocurrent of the photosensitive device 30 using transparent ITO for the first bonding electrode 35 shown in FIG. 6 can be increased by about 17%.
  • the material of the first bonding electrode 35 and the material of the second electrode 33 may be the same material, for example, both may be ITO materials. Since the matching degree between the same materials is higher and the noise is lower, the dark current of the photosensitive device 30 can be reduced, and the sensitivity of the photosensitive device 30 can be improved. Compared with FIG. 6 and FIG. 2, the dark current of the photosensitive device 30 with the same material overlapped as shown in FIG. 6 can be reduced by about 60% relative to the photosensitive device overlapped with different materials.
  • the thin film transistor 20 includes a gate 21 formed on a second surface S2 of the base substrate 10 opposite to the first surface S1, and a gate insulating layer 22 covering the gate 21 ,
  • the source 24 and the drain 25 are respectively connected to the active layer 23; the source 24 or the drain 25 is connected to the first conductive substructure 11 of the base substrate 10 through the third via 221 on the gate insulating layer 22 ;
  • the passivation layer 26 covers the source 24, the drain 25, the active layer 23 and the gate insulating layer 22. It should be noted that the positions of the source 24 and the drain 25 of the thin film transistor 20 can be interchanged, and the positions of the source and the drain shown in each figure do not limit the present invention.
  • the orthographic projection of the photosensitive layer 32 on the base substrate 10 overlaps the orthographic projection of the active layer 23 on the base substrate 10.
  • the orthographic projection of the photosensitive layer 32 on the base substrate 10 covers the orthographic projection of the active layer 23 on the base substrate 10.
  • the fingerprint recognition sensor since the thin film transistor 20 and the photosensitive device 30 can be respectively arranged on two opposite surfaces of the base substrate 10, instead of on the same side of the base substrate 10. Therefore, when the photosensitive layer 32 of the photosensitive device 30 is deposited and formed in a hydrogen ion environment, the base substrate 10 can play a natural protective role, thereby preventing the active layer 23 of the thin film transistor 20 from being conductive by hydrogen ions.
  • the fingerprint recognition sensor reduces the resin layer, the second passivation layer and the buffer layer, thereby reducing the three-layer processing technology and simplifying the fingerprint recognition sensor The preparation process. In addition, while reducing the three layers of film, the transmittance of light can be increased, so that more light can be received by the photosensitive device 30, and the signal amount of the photocurrent signal can be increased.
  • the fingerprint recognition sensor may include a base substrate, a thin film transistor, and a photosensitive device.
  • the thin film transistor, the base substrate and the photosensitive device are stacked in a thickness direction perpendicular to the base substrate.
  • the base substrate includes a conductive structure penetrating the base substrate in the thickness direction of the base substrate, and the photosensitive device can be connected to the thin film transistor through the conductive structure of the base substrate.
  • the thin film transistor, the base substrate, and the photosensitive device are stacked and arranged in a thickness direction perpendicular to the base substrate, that is, the thin film transistor and the photosensitive device can be respectively arranged on two opposite surfaces of the base substrate.
  • the two can be electrically connected through the conductive structure of the base substrate to realize the control of the photosensitive device. Therefore, there is no need to compress the installation space of the photosensitive device when arranging the thin film transistor, so that the effective photosensitive area of the photosensitive device can be increased, thereby enhancing The photocurrent signal generated by the fingerprint recognition sensor improves the accuracy of fingerprint recognition.
  • Fig. 7 shows a step flow chart of a method for preparing a fingerprint identification sensor according to an embodiment of the present invention.
  • the method may include the following steps:
  • Step 701 Provide a base substrate; the base substrate includes a conductive structure that penetrates the base substrate in a direction perpendicular to the base substrate (ie, a thickness direction).
  • a through hole may be formed on the base substrate 10 along the thickness direction perpendicular to the base substrate 10 by means of laser drilling or the like, and then the through hole may be formed in the through hole.
  • the conductive structure 11 of the base substrate 10 may include discrete first conductive substructures 111 and second conductive substructures 112, and the first conductive substructures 111 and the second conductive substructures 112 are in the thickness direction of the base substrate 10. All pass through the base substrate 10.
  • Step 702 forming a thin film transistor on a second surface of the base substrate opposite to the first surface, that is, forming a thin film transistor on one side of the base substrate.
  • the base substrate 10 may include a first surface S1 and a second surface S2 opposite to each other.
  • the first surface S1 of the base substrate 10 may be used to prepare the photosensitive device 30 and the second surface S2 of the base substrate 10
  • the surface S2 can be used to prepare the thin film transistor 20.
  • this step can be specifically implemented through the following substeps (1) to (5), including:
  • Sub-step (1) forming a gate 21 on the second surface S2 of the base substrate 10 opposite to the first surface S1.
  • the sub-step (1) may specifically include: forming the gate 21 and the third electrode 40 in the same layer on the second surface S2 of the base substrate 10 opposite to the first surface S1.
  • the third electrode 40 is connected to the second conductive substructure 112, as shown in FIG. 9.
  • the third electrode 40 can be configured to input the working voltage to the photosensitive device through the second conductive substructure 112 and the first bonding electrode.
  • the third electrode 40 is the input terminal of the working voltage of the photosensitive device, and the first bonding electrode belongs to the photosensitive device. 30.
  • the gate 21 and the third electrode 40 can be formed in the same layer through a single photolithography process, thereby reducing the manufacturing process of the fingerprint recognition sensor.
  • the material of the gate 21 may include at least one of Mo, Al, Cu, and Ti, which is not specifically limited in the embodiment of the present invention.
  • Sub-step (2) forming a gate insulating layer covering the gate.
  • Sub-step (3) forming an active layer on the gate insulating layer.
  • the gate insulating material layer and the active material layer can be sequentially formed through a deposition process, and then the active material layer can be wet-etched through the first photolithography process to obtain the active layer 23, and then the second time In the photolithography process, dry etching is performed on the gate insulating material layer to obtain the third via 221 extending to the first conductive substructure 111, thereby obtaining the gate insulating layer 22, as shown in FIG. 10.
  • the material of the gate 21 may include at least one of SiO, SiON, and SiN
  • the material of the active layer 23 may include at least one of a-Si, IGZO, IZO, IGZXO, and IGZYO. This is not specifically limited.
  • Sub-step (4) source and drain are formed in the same layer; the source and drain are respectively connected to the active layer; the source or the drain is connected to the first through hole on the gate insulating layer and the first The conductive substructure is connected.
  • the source 24 and the drain 25 can be formed in the same layer through a photolithography process. In specific applications, the source 24 and the drain 25 can be interchanged in position, which is not specifically limited in the embodiment of the present invention. .
  • the source 24 and the drain 25 are respectively connected to the active layer 23, and the source 24 or the drain 25 is connected to the first conductive substructure 111 through the third via 221 on the gate insulating layer 22.
  • the material of the source 24 and the drain 25 may include at least one of Mo, Al, Cu, Nd, and Ti, which is not specifically limited in the embodiment of the present invention.
  • Sub-step (5) forming a passivation layer; the passivation layer covers the source electrode, the drain electrode, the active layer and the gate insulating layer.
  • the passivation layer 26 covering the source electrode 24, the drain electrode 25, the active layer 23, and the gate insulating layer 22 may be formed through a deposition process.
  • the material of the passivation layer 26 may include at least one of SiOx, SiNx, SiON, and AlOx, which is not specifically limited in the embodiment of the present invention.
  • the thin film transistor 20 can be formed on the second surface S2 of the base substrate 10.
  • Step 703 forming a photosensitive device on the first surface of the base substrate, that is, forming a photosensitive device on the side of the base substrate away from the thin film transistor; the thin film transistor, the base substrate and the photosensitive device are stacked in the thickness direction of the base substrate; The photosensitive device is connected to the thin film transistor through the conductive structure of the base substrate.
  • this step can be specifically implemented through the following substeps (6) to (10), including:
  • Sub-step (6) forming a first electrode on the first surface of the base substrate; the first electrode is connected to the first conductive substructure.
  • the first electrode 31 may be formed on the first surface S1 of the base substrate 10 through a deposition process and a photolithography process, wherein the first electrode 31 may be connected to the first conductive substructure 111.
  • the fingerprint recognition sensor may further include a second bonding electrode 01. Accordingly, the first electrode 31 and the second electrode 31 may be formed on the first surface S1 of the base substrate 10 in the same layer through a deposition process and a photolithography process. Two overlapping electrodes 01, as shown in Figure 13. Among them, the second bonding electrode 01 can be used to bridge the third electrode 40 and the first bonding electrode of the photosensitive device 30.
  • the material of the first electrode 31 and the second bonding electrode 01 may include at least one of Mo, Al, Cu, Nd, and Ti, which is not specifically limited in the embodiment of the present invention.
  • the base substrate 10 can play a natural protective role, thereby preventing the active layer of the thin film transistor 20 from being conductive by hydrogen ions.
  • Sub-step (7) forming a photosensitive layer on the side of the first electrode away from the base substrate.
  • Sub-step (8) forming a second electrode on the side of the photosensitive layer away from the first electrode.
  • the photosensitive material layer and the second electrode material layer may be sequentially formed through a deposition process, and then the second electrode material layer may be wet-etched through the first photolithography process, and then the second electrode material layer may be wet-etched through the second photolithography process.
  • RIE reactive Ion Etching, reactive ion etching
  • dry etching the photosensitive material layer to obtain the photosensitive layer 32 and then through the third photolithography process, the second electrode material layer after the first photolithography
  • the wet etching is performed, so that the second electrode 33 can be obtained, as shown in FIG. 14.
  • the area of the second electrode 33 may be smaller than the area of the photosensitive layer 32, so that the leakage current at the edge of the photosensitive device 30 can be reduced, and the sensitivity of the photosensitive device 30 can be improved.
  • the material of the second electrode 33 may be ITO, etc., which is not specifically limited in the embodiment of the present invention.
  • Sub-step (9) forming a protective layer; the protective layer covers the first electrode, the photosensitive layer, the second electrode and the first surface of the base substrate.
  • the protective layer 34 covering the first electrode 31, the photosensitive layer 32, the second electrode 33, and the first surface S1 of the base substrate 10 can be formed by a deposition process, and then the protective layer 34 can be formed by a photolithography process.
  • a first via 341 is formed at a position of 34 corresponding to the second electrode 33, and a second via 342 is formed at a position of the protective layer 34 corresponding to the second conductive substructure 112, as shown in FIG.
  • the material of the protective layer 34 may include at least one of SiO, SiN, and SiON, which is not specifically limited in the embodiment of the present invention.
  • Sub-step (10) forming a first lap electrode; the first lap electrode is located on the side of the protection layer away from the base substrate; the first lap electrode is connected to the second electrode through the first via hole of the protection layer, the first The bonding electrode is connected to the second conductive substructure through the second via hole of the protection layer.
  • the first bonding electrode 35 may be located on the side of the protective layer 34 away from the base substrate. As shown in FIG. 5, the first bonding electrode 35 may be connected to the second electrode 33 through the first via 341 of the protective layer 34 The first bonding electrode 35 may also be connected to the second conductive substructure 112 through the second via 342 of the protection layer 34, or through the second via 342 of the protection layer 34, and the second bonding electrode 01 and the second The conductive substructure 112 is connected.
  • the material of the first bonding electrode 35 may be a transparent electrode material, such as ITO, so that the part of the photosensitive device shielded by the first bonding electrode 35 can be effectively sensitized, thereby increasing the effective sensitization of the fingerprint recognition sensor area.
  • the material of the second electrode 33 and the material of the first bonding electrode 35 may be the same material, for example, both are ITO, which is not specifically limited in the embodiment of the present invention. Since the matching degree between the same materials is higher and the noise is lower, the dark current of the photosensitive device 30 can be reduced, and the sensitivity of the photosensitive device 30 can be improved.
  • the photosensitive device 30 can be formed on the first surface S1 of the base substrate 10. After the thin film transistor 20 and the photosensitive device 30 are respectively formed on the two opposite surfaces of the base substrate 10, a fingerprint recognition sensor can be obtained.
  • step 702 and step 703 can be interchanged.
  • the foregoing only provides one or more forming methods of each structure, and one or more optional materials. It is understandable that in specific applications, other methods or materials may also be used to form each structure. The embodiment of the invention does not specifically limit this.
  • a base substrate may be provided first, the base substrate includes a conductive structure penetrating the base substrate in the thickness direction of the base substrate, and then the base substrate A photosensitive device is formed on the first surface of the substrate, and a thin film transistor is formed on the second surface of the base substrate opposite to the first surface.
  • the thin film transistor, the base substrate and the photosensitive device are stacked and arranged along the thickness direction of the base substrate, and the photosensitive device can be connected to the thin film transistor through the conductive structure of the base substrate.
  • a thin film transistor and a photosensitive device can be respectively arranged on the two opposite surfaces of the base substrate, and the two can be electrically connected through the conductive structure of the base substrate to realize the control of the photosensitive device.
  • An embodiment of the present invention also discloses a display device including the above fingerprint identification sensor.
  • the fingerprint recognition sensor in the display device may include a base substrate, a thin film transistor, and a photosensitive device.
  • the thin film transistor, the base substrate and the photosensitive device are stacked in a thickness direction of the base substrate.
  • the base substrate includes a conductive structure penetrating the base substrate in the thickness direction of the base substrate, and the photosensitive device can be connected to the thin film transistor through the conductive structure of the base substrate.
  • the thin film transistor, the base substrate, and the photosensitive device are stacked and arranged along the thickness direction of the base substrate, that is, the thin film transistor and the photosensitive device can be respectively arranged on two opposite surfaces of the base substrate, and two It can be electrically connected through the conductive structure of the base substrate to realize the control of the photosensitive device. Therefore, there is no need to compress the installation space of the photosensitive device when installing the thin film transistor, so that the effective photosensitive area of the photosensitive device can be increased, which can enhance fingerprint recognition
  • the photocurrent signal generated by the sensor improves the accuracy of fingerprint recognition.

Abstract

一种指纹识别传感器及其制备方法、以及显示装置。该指纹识别传感器包括衬底基板(10)；薄膜晶体管(20)，位于衬底基板(10)的一侧；以及光敏器件(30)，位于衬底基板(10)远离薄膜晶体管(20)的一侧，薄膜晶体管(20)、衬底基板(10)和光敏器件(30)沿垂直于衬底基板(10)的厚度方向依次层叠设置，衬底基板(10)包括在垂直于衬底基板(10)的厚度方向上贯穿衬底基板(10)的导电结构(11)，光敏器件(30)通过导电结构(11)与薄膜晶体管(20)连接。由此，在设置薄膜晶体管时无需压缩光敏器件的设置空间，从而光敏器件的有效感光面积可以增大，进而可以提高指纹识别的准确度。

Description

指纹识别传感器及其制备方法、以及显示装置
本申请要求于2019年04月09日递交的中国专利申请第201910282112.3号的优先权，在此全文引用上述中国专利申请公开的内容以作为本申请的一部分。
技术领域
本公开实施例涉及一种指纹识别传感器及其制备方法、以及显示装置。
背景技术
目前，配备有OLED(Organic Light-Emitting Diode，有机发光二极管)显示装置的电子设备越来越多，用户对于电子设备的安全性能也提出了更高的要求，因此，指纹识别等安全验证功能，被越来越多地集成在OLED显示装置中。
发明内容
本公开实施例提供一种指纹识别传感器及其制备方法、以及显示装置，以解决现有的指纹识别传感器中光敏器件与薄膜晶体管相邻设置，使得光敏器件的设置空间较小，导致指纹识别传感器的有效感光面积较小，指纹识别准确度较低的问题。
本公开至少一个实施例提供一种指纹识别传感器，其包括：衬底基板；薄膜晶体管，位于所述衬底基板的一侧；以及光敏器件，位于所述衬底基板远离所述薄膜晶体管的一侧，所述薄膜晶体管、所述衬底基板和所述光敏器件沿垂直于所述衬底基板的厚度方向依次层叠设置，所述衬底基板包括在垂直于所述衬底基板的厚度方向上贯穿所述衬底基板的导电结构，所述光敏器件通过所述导电结构与所述薄膜晶体管连接。
例如，在本公开一实施例提供的指纹识别传感器中，所述导电结构包括分立的第一导电子结构和第二导电子结构，所述第一导电子结构和所述第二导电子结构在所述衬底基板的厚度方向上均贯穿所述衬底基板；所述光敏器件包括：位于所述衬底基板的第一表面上的第一电极；位于所述第一电极远离所述衬底基板的一侧的光敏层；以及位于所述光敏层远离所述第一电极的一侧的第二电极，所述第一电极与所述第一导电子结构连接，所述第二电极被配置为与 所述第二导电子结构电性相连。
例如，在本公开一实施例提供的指纹识别传感器中，所述光敏器件包括光敏层，所述薄膜晶体管包括有源层，所述光敏层在所述衬底基板上的正投影与所述有源层在所述衬底基板上的正投影交叠。
例如，在本公开一实施例提供的指纹识别传感器中，所述光敏层在所述衬底基板上的正投影覆盖所述有源层在所述衬底基板上的正投影。
例如，在本公开一实施例提供的指纹识别传感器中，所述光敏器件还包括：保护层，覆盖所述第一电极、所述光敏层、所述第二电极和所述衬底基板的第一表面；以及第一搭接电极，位于所述保护层远离所述光敏层的一侧，所述保护层包括第一过孔和第二过孔，所述第一搭接电极通过所述保护层中的所述第一过孔与所述第二电极连接，所述第一搭接电极通过所述保护层中的第二过孔与所述第二导电子结构连接。
例如，本公开一实施例提供的指纹识别传感器还包括：第三电极，位于所述衬底基板的与所述第一表面相背的第二表面上，且与所述第二导电子结构连接；所述第三电极被配置为通过所述第二导电子结构及所述第一搭接电极向所述光敏器件输入工作电压。
例如，在本公开一实施例提供的指纹识别传感器中，所述第一搭接电极的材料为透明电极材料。
例如，在本公开一实施例提供的指纹识别传感器中，所述薄膜晶体管还包括：栅极，位于所述衬底基板远离所述光敏器件的一侧的表面上；栅极绝缘层，位于所述栅极远离所述衬底基板的一侧，且覆盖所述栅极；以及源极和漏极，
其中，所述有源层位于所述栅极绝缘层远离所述栅极的一侧，所述源极和漏极位于所述栅极绝缘层远离所述有源层的一侧，所述源极和所述漏极分别与所述有源层相连，所述栅极绝缘层包括第三过孔，所述源极或所述漏极通过所述栅极绝缘层中第三过孔与所述衬底基板的第一导电子结构连接。
例如，本公开一实施例提供的指纹识别传感器还包括：钝化层，位于所述源极和所述漏极远离所述有源层的一侧，且覆盖所述源极、所述漏极、所述有源层及所述栅极绝缘层。
本公开至少一个实施例还提供一种指纹识别传感器的制备方法，其包括：提供衬底基板，所述衬底基板包括在垂直于所述衬底基板的厚度方向上贯穿所述衬底基板的导电结构；在衬底基板的一侧形成薄膜晶体管；以及在衬底基板 远离所述薄膜晶体管的一侧形成光敏器件，所述薄膜晶体管、所述衬底基板和所述光敏器件沿垂直于所述衬底基板的厚度方向依次层叠设置，所述光敏器件通过所述导电结构与所述薄膜晶体管连接。
例如，在本公开一实施例提供的制备方法中，所述导电结构包括分立的第一导电子结构和第二导电子结构，所述第一导电子结构和所述第二导电子结构在所述衬底基板的厚度方向上均贯穿所述衬底基板；在衬底基板远离所述薄膜晶体管的一侧形成光敏器件包括：在所述衬底基板的第一表面上形成第一电极；在所述第一电极远离所述衬底基板的一侧形成光敏层；以及在所述光敏层远离所述第一电极的一侧形成第二电极，所述第一电极与所述第一导电子结构连接，所述第二电极被配置为与所述第二导电子结构电性相连。
例如，在本公开一实施例提供的制备方法中，在衬底基板远离所述薄膜晶体管的一侧形成光敏器件还包括：在所述第二电极远离所述光敏层的一侧形成保护层，所述保护层覆盖所述第一电极、所述光敏层、所述第二电极和所述衬底基板的第一表面；以及在所述保护层远离光敏层的一侧形成第一搭接电极，所述第一搭接电极位于所述保护层远离所述光敏层的一侧所述保护层包括第一过孔和第二过孔，所述第一搭接电极通过所述保护层中的所述第一过孔与所述第二电极连接，所述第一搭接电极通过所述保护层中的第二过孔与所述第二导电子结构连接。
例如，在本公开一实施例提供的制备方法还包括：在所述衬底基板的与所述第一表面相背的第二表面上形成第三电极，所述第三电极与所述第二导电子结构连接；所述第三电极被配置为通过所述第二导电子结构及所述第一搭接电极向所述光敏器件输入工作电压。
例如，在本公开一实施例提供的制备方法中，在衬底基板的一侧形成薄膜晶体管包括：在衬底基板的一侧形成栅极；在所述栅极远离所述衬底基板的一侧形成栅极绝缘层，所述栅极绝缘层覆盖所述栅极；在所述栅极绝缘层远离所述栅极的一侧形成有源层；以及在所述有源层远离所述栅极绝缘层的一侧形成源极和漏极，所述源极和所述漏极分别与所述有源层相连，所述栅极绝缘层包括第三过孔，所述源极或所述漏极通过所述栅极绝缘层中第三过孔与所述衬底基板的第一导电子结构连接。
例如，在本公开一实施例提供的制备方法中，所述光敏层在所述衬底基板上的正投影与所述有源层在所述衬底基板上的正投影交叠。
例如，在本公开一实施例提供的制备方法中，所述光敏层在所述衬底基板上的正投影覆盖所述有源层在所述衬底基板上的正投影。
例如，本公开一实施例提供的制备方法还包括：在所述源极和所述漏极远离所述有源层的一侧形成钝化层，所述钝化层覆盖所述源极、所述漏极、所述有源层及所述栅极绝缘层。
本公开至少一个实施例还提供一种显示装置，包括上述任一项所述的指纹识别传感器。
附图说明
为了更清楚地说明本公开实施例的技术方案，下面将对实施例的附图作简单地介绍，显而易见地，下面描述中的附图仅仅涉及本公开的一些实施例，而非对本公开的限制。
图1示出了一种指纹识别传感器的截面示意图；
图2示出了一种光敏器件的I-V特性曲线；
图3示出了一种薄膜晶体管的I-V特性曲线；
图4示出了本发明一实施例提供的一种指纹识别传感器的截面示意图；
图5示出了本发明一实施例提供的另一种指纹识别传感器的截面示意图；
图6示出了本发明一实施例提供的一种第一搭接电极和第二电极均采用透明ITO的光敏器件的I-V特性曲线；
图7示出了本发明一实施例提供的一种指纹识别传感器的制备方法的流程图；
图8示出了本发明一实施例提供的的一种衬底基板的截面示意图；
图9示出了本发明一实施例提供的一种形成栅极和第三电极后的指纹识别传感器的截面示意图；
图10示出了本发明一实施例提供的一种形成栅极绝缘层和有源层后的指纹识别传感器的截面示意图；
图11示出了本发明一实施例提供的一种形成源极和漏极后的指纹识别传感器的截面示意图；
图12示出了本发明一实施例提供的一种形成钝化层后的指纹识别传感器的截面示意图；
图13示出了本发明一实施例提供的一种形成第一电极和第二搭接电极的 指纹识别传感器的截面示意图；
图14示出了本发明一实施例提供的一种形成光敏层和第二电极后的指纹识别传感器的截面示意图；以及
图15示出了本发明一实施例提供的一种形成保护层后的指纹识别传感器的截面示意图。
具体实施方式
为使本公开实施例的目的、技术方案和优点更加清楚，下面将结合本公开实施例的附图，对本公开实施例的技术方案进行清楚、完整地描述。显然，所描述的实施例是本公开的一部分实施例，而不是全部的实施例。基于所描述的本公开的实施例，本领域普通技术人员在无需创造性劳动的前提下所获得的所有其他实施例，都属于本公开保护的范围。
除非另外定义，本公开使用的技术术语或者科学术语应当为本公开所属领域内具有一般技能的人士所理解的通常意义。本公开中使用的“第一”、“第二”以及类似的词语并不表示任何顺序、数量或者重要性，而只是用来区分不同的组成部分。“包括”或者“包含”等类似的词语意指出现该词前面的元件或者物件涵盖出现在该词后面列举的元件或者物件及其等同，而不排除其他元件或者物件。“连接”或者“相连”等类似的词语并非限定于物理的或者机械的连接，而是可以包括电性的连接，不管是直接的还是间接的。
在目前的OLED显示装置中，指纹识别传感器可以包括相邻设置的光敏器件和薄膜晶体管，其中，薄膜晶体管的设置需要占据一定的空间，从而将使得光敏器件的设置空间被压缩，而指纹识别传感器的有效感光面积均来源于光敏器件，因此，光敏器件的设置空间被压缩，将导致指纹识别传感器的有效感光面积较小，进而导致指纹识别传感器产生的光电流信号较弱，使得指纹识别的准确度较低。
图1为一种指纹识别传感器的截面示意图。如图1所示，该指纹识别传感器包括薄膜晶体管1和光敏器件2；薄膜晶体管1和光敏器件2可以设置在衬底基板3的同侧，且二者可以相邻设置。
例如，如图1所示，薄膜晶体管1可以包括形成在衬底基板3上的栅极101、覆盖栅极101的栅极绝缘层102、形成在栅极绝缘层102上的有源层103、分别连接有源层103的源极104和漏极105，以及覆盖上述各个结构的第一钝化 层106。光敏器件2可以包括形成在第一钝化层106上的第一电极201、形成在第一电极201上的光敏层202、形成在光敏层202上的第二电极203、覆盖上述各个结构的保护层204、覆盖保护层204的树脂层205、覆盖树脂层205的第二钝化层206、形成在第二钝化层206上的搭接电极207(通常称作Top Metal，顶电极)，以及覆盖第二钝化层206和搭接电极207的缓冲层208。
第一电极201通过第一钝化层106中的过孔与薄膜晶体管1的源极104连接；第二电极203的材料通常为ITO(Indium Tin Oxides，铟锡氧化物)；搭接电极207通过树脂层205及树脂层205中的过孔与第二电极203连接；搭接电极207通常采用导电的金属材料。
在实际应用中，发明人发现图1所示的指纹识别传感器至少存在以下问题：
问题1：薄膜晶体管1和光敏器件2设置在衬底基板3的同侧，且二者相邻设置，从而导致薄膜晶体管1的设置将会使得光敏器件2的空间被压缩，进而减小了光敏器件2的有效感光面积。对于高密度指纹识别传感器设计的显示装置，薄膜晶体管1和光敏器件2相邻设置的方式，则对光敏器件2的有效感光面积影响更大。例如，当每英寸显示装置包括的指纹识别传感器数量从400个提升至500个时，光敏器件2的有效感光面积将锐减约60％，光电流信号量亦锐减约60％，将严重影响光电流信号的检测。
问题2：位于光敏器件2顶部的搭接电极207通常采用导电的金属材料，而金属材料的透光率较低，如此，将导致被搭接电极207遮挡的光敏器件部分无法进行有效感光，从而进一步降低了指纹识别传感器的有效感光面积。例如，搭接电极207对指纹识别传感器的有效感光面积影响较大，尤其是对于高密度指纹识别传感器设计的显示装置，例如当每英寸显示装置包括500个指纹识别传感器时，遮挡光敏器件2的搭接电极部分的面积与指纹识别传感器的有效感光面积之间的面积占比约为17％，当指纹识别传感器密度更高时，这一面积占比将更高，相应的，搭接电极207对指纹识别传感器的有效感光面积影响也更大。
图2为一种光敏器件2的I-V(电流-电压)特性曲线；如图2所示，光敏器件2通常可以在-4V(伏特)的负偏压下工作，当向光敏器件2输入-4V的负偏压时，光敏器件2输出的光电流如图2所示。指纹识别传感器的有效感光面积越小，则光敏器件2的光电流越小，指纹识别的准确度就越低。
问题3：第二电极203和搭接电极207采用不同材料，将导致光敏器件2 的暗电流较大，导致光敏器件2的灵敏度较低。例如，由于第二电极203和搭接电极207采用不同材料，因此二者之间的材料匹配度较低，噪声更大。光敏器件2输出的暗电流如图2所示，其中，光敏器件2的暗电流越大，则光敏器件2的灵敏度就越低，指纹识别的准确度也就越低。
问题4：薄膜晶体管1的有源层103极易在光敏器件2的制备过程中被导体化，从而降低了光敏器件2产生的光电流信号量。例如，由于薄膜晶体管1和光敏器件2设置在衬底基板3的同侧，而薄膜晶体管1的有源层103极易受到氢离子干扰而在一定程度上导体化，也即是薄膜晶体管1在关闭状态仍然能够传导较多的电荷。而光敏器件2的光敏层202需要在富含氢离子的环境中沉积形成，因此，在沉积光敏层202时，有源层103极易在氢离子环境中被导体化，从而在薄膜晶体管1关闭时，光敏器件2存储的部分光生电荷会损失掉，从而降低光电流信号量。
图3示出了一种薄膜晶体管1的I-V特性曲线，参照图3，在栅极电压小于-10V时，薄膜晶体管1为关闭状态，但其漏极电流已高达10 -11次方的数量级，而正常的薄膜晶体管1为关闭状态时，其漏极电流应为10 -15次方的数量级，因此，图3对应的薄膜晶体管1的有源层103在一定程度上已被导体化，从而在薄膜晶体管1关闭时，光敏器件2产生的部分光生电荷仍然会通过有源层沟道被释放，从而降低了光电流信号量。
问题5：保护层204之后需要形成的膜层较多，而光线在每个膜层均会存在损失，从而将降低光线的透过率，并且，也需要进行更多的沉积工艺、光刻工艺等膜层加工工艺，从而使得指纹识别传感器的制备过程较为繁琐。
对此，本公开实施例提供一种指纹识别传感器及其制备方法、以及显示装置。该指纹识别传感器包括衬底基板；薄膜晶体管，位于衬底基板的一侧；以及光敏器件，位于衬底基板远离薄膜晶体管的一侧，薄膜晶体管、衬底基板和光敏器件沿垂直于衬底基板的厚度方向依次层叠设置，衬底基板包括在垂直于衬底基板的厚度方向上贯穿衬底基板的导电结构，光敏器件通过导电结构与薄膜晶体管连接。由此，该指纹识别传感器通过将光敏器件和薄膜晶体管形成在衬底基板相互背离的两侧，并通过衬底基板中的导电结构相连，可避免光敏器件的空间被压缩，从而使得光敏器件的有效感光面积可以增大，也即是指纹识别传感器的有效感光面积增大，从而可以增强指纹识别传感器产生的光电流信号，进而提高了指纹识别的准确度。
下面，结合附图对本公开实施例提供的指纹识别传感器及其制备方法、以及显示装置进行详细的说明。
本公开一实施例提供一种指纹识别传感器。图4示出了本发明一实施例提供的一种指纹识别传感器的截面示意图；如图4所示，该指纹识别传感器包括衬底基板10、薄膜晶体管20(Thin Film Transistor，TFT)和光敏器件30，薄膜晶体管20、衬底基板10和光敏器件30沿垂直于衬底基板10的方向(即厚度方向)层叠设置，即薄膜晶体管20位于衬底基板10的一侧，光敏器件30位于衬底基板10远离薄膜晶体管20的一侧。衬底基板10可以包括在衬底基板10的厚度方向上贯穿衬底基板10的导电结构11，光敏器件30可以通过衬底基板10的导电结构11与薄膜晶体管20连接。薄膜晶体管20可以用于释放光敏器件30产生的光生电荷。
对于上述的问题1，在本发明实施例提供的指纹识别传感器中，薄膜晶体管20、衬底基板10和光敏器件30可以沿垂直于衬底基板10的厚度方向层叠设置，也即是薄膜晶体管20和光敏器件30可以分别设置在衬底基板10相背的两个表面，且二者可以通过衬底基板10的导电结构11电连接，以实现光敏器件30的控制。因此，在设置薄膜晶体管20时无需压缩光敏器件30的设置空间，从而使得光敏器件30的有效感光面积可以增大，也即是指纹识别传感器的有效感光面积增大，从而可以增强指纹识别传感器产生的光电流信号，进而提高了指纹识别的准确度。
例如，如图4所示，衬底基板10的导电结构11可以包括分立的第一导电子结构111和第二导电子结构112，第一导电子结构111和第二导电子结构112在垂直于衬底基板10的厚度方向上均贯穿衬底基板10。例如，导电结构11的材料可以为铜金属等导电材料，本发明实施例对此不作具体限定。
相应的，光敏器件30包括形成在衬底基板10的第一表面S1上的第一电极31、形成在第一电极31上的光敏层32、形成在光敏层32上的第二电极33、保护层34，以及第一搭接电极35。其中，第一电极31与第一导电子结构111连接；保护层34覆盖第一电极31、光敏层32、第二电极33及衬底基板10的第一表面S1；第一搭接电极35位于保护层34远离衬底基板10的一侧；第一搭接电极35可以通过保护层34的第一过孔341与第二电极33连接，第一搭接电极35可以通过保护层34的第二过孔342与第二导电子结构112连接。
例如，光敏器件30可以为PIN光电二极管，相应的，光敏层32具体可以 包括沿衬底基板10的厚度方向层叠设置的N型半导体层、本征半导体层及P型半导体层，N型半导体层靠近第一电极31设置。
在本公开实施例提供的指纹识别传感器工作时，可以通过第二电极33向光敏层32施加工作所需的负偏压，进而当具有足够能量的光子入射到光敏层32时，可以激发光敏层32产生光生电荷，从而形成指纹识别所需的光电流信号。
第一电极31可以通过第一导电子结构111与薄膜晶体管20的源极或漏极连接，为了便于描述，以第一电极31通过第一导电子结构111与薄膜晶体管20的源极连接为例进行说明，可以理解的是，薄膜晶体管20的源极和漏极可以位置互换。在光敏层32形成光电流信号之后，显示装置即可根据该光电流信号形成指纹图像，进而进行指纹识别，之后，与光敏层32连接的第一电极31可以通过薄膜晶体管20释放光生电荷。在光敏层32工作时，薄膜晶体管20的栅极可以处于关闭状态，进而光敏层32产生的光生电荷可以依次通过第一电极31、第一导电子结构111、薄膜晶体管20的源极导入至薄膜晶体管20的有源层，并在有源层累积，当薄膜晶体管20的栅极打开时，光生电荷可以从通过有源层沟道流向薄膜晶体管20的漏极，从而导出。
另外，对于第一搭接电极35与第二导电子结构112连接方式，在一种实现方式中，参照图4，第一搭接电极35可以直接通过保护层34的第二过孔342与第二导电子结构112连接。在另一种实现方式中，参照图5，指纹识别传感器还可以包括第二搭接电极01，其中，第二搭接电极01可以与光敏器件30的第一电极31同层设置，且第二搭接电极01和第一电极31的厚度可以相同，第二搭接电极01可以分别与第一搭接电极35和第二导电子结构112连接。如图4所示，保护层34的第二过孔342的底部也即第二搭接电极01，相应的，第一搭接电极35可以通过保护层34的第二过孔342及第二搭接电极01，与第二导电子结构112连接。本发明实施例对于第一搭接电极35与第二导电子结构112连接不作具体限定。
在一些示例中，参照图4，第二电极33的面积可以小于光敏层32的面积，从而可以降低光敏器件30边缘的漏电流，进而能够提高光敏器件30的灵敏度。
在一些示例中，参照图4，指纹识别传感器还可以包括第三电极40，第三电极40形成在衬底基板10的与第一表面S1相背的第二表面S2上，且与第二导电子结构112连接。第三电极40可以被配置为通过第二导电子结构112及 第一搭接电极35向光敏器件30输入工作电压，也即一负偏压。也即是可以向第三电极40输入光敏器件30所需的工作电压，进而第三电极40可以依次通过衬底基板10的第二导电子结构112、第一搭接电极35及第二电极33，将该工作电压输入至光敏层32。
在一些示例中，第三电极40可以与薄膜晶体管20的栅极同层设置，从而通过一次构图工艺即可同时形成第三电极40和薄膜晶体管20的栅极，如此，能够简化指纹识别传感器的制备流程。
对于上述的问题2，在本发明实施例提供的指纹识别传感器中，第一搭接电极35的材料可以为透明电极材料，例如ITO等材料，本发明实施例对此不作具体限定。也即是可以采用透明电极材料制备第一搭接电极35，从而被第一搭接电极35遮挡的光敏器件部分能够进行有效感光，进而增大了指纹识别传感器的有效感光面积。图6示出了一种第一搭接电极35和第二电极33均采用透明ITO的光敏器件30的I-V(电流-电压)特性曲线，对照图6与图2，相对于搭接电极采用金属材料的光敏器件，图6所示的第一搭接电极35采用透明ITO的光敏器件30的光电流能够提高约17％。
对于上述的问题3，在本发明实施例提供的指纹识别传感器中，第一搭接电极35的材料和第二电极33的材料可以为同种材料，例如可以均为ITO材料。由于同种材料之间的匹配度更高，噪声更低，因此，能够降低光敏器件30的暗电流，进而提高了光敏器件30的灵敏度。对照图6与图2，相对于不同材料搭接的光敏器件，图6所示的同种材料搭接的光敏器件30的暗电流能够降低约60％。
在一些实例中，如图4所示，薄膜晶体管20包括形成在衬底基板10的与第一表面S1相背的第二表面S2上的栅极21、覆盖栅极21的栅极绝缘层22、形成在栅极绝缘层22上的有源层23、同层设置的源极24和漏极25，以及钝化层26。其中，源极24和漏极25分别与有源层23连接；源极24或漏极25通过栅极绝缘层22上的第三过孔221与衬底基板10的第一导电子结构11连接；钝化层26覆盖源极24、漏极25、有源层23及栅极绝缘层22。需要说明的是，薄膜晶体管20的源极24和漏极25可以位置互换，各个图示中所示的源极位置和漏极位置不对本发明构成限定。
例如，如图4所示，光敏层32在衬底基板10上的正投影与有源层23在衬底基板10上的正投影交叠。又例如，光敏层32在衬底基板10上的正投影 覆盖有源层23在衬底基板10上的正投影。
对于上述的问题4，在本发明实施例提供的指纹识别传感器中，由于薄膜晶体管20和光敏器件30可以分别设置在衬底基板10相背的两个表面，而不在衬底基板10的同侧，因此，在氢离子环境下沉积形成光敏器件30的光敏层32时，衬底基板10可以起到天然的保护作用，从而避免薄膜晶体管20的有源层23被氢离子导体化。对于上述的问题5，在本发明实施例提供的指纹识别传感器中，指纹识别传感器减少了树脂层、第二钝化层和缓冲层，从而可以减少3道膜层加工工艺，简化了指纹识别传感器的制备过程。另外，减少3层膜层的同时，还能够提高光线的透过率，从而可以有更多的光线被光敏器件30接收，提高了光电流信号的信号量。
本发明实施例提供的指纹识别传感器可以包括衬底基板、薄膜晶体管和光敏器件，薄膜晶体管、衬底基板和光敏器件沿垂直于衬底基板的厚度方向层叠设置。衬底基板包括在衬底基板的厚度方向上贯穿衬底基板的导电结构，光敏器件可以通过衬底基板的导电结构与薄膜晶体管连接。在本发明实施例中，薄膜晶体管、衬底基板和光敏器件沿垂直于衬底基板的厚度方向层叠设置，也即是薄膜晶体管和光敏器件可以分别设置在衬底基板相背的两个表面，且二者可以通过衬底基板的导电结构电连接，以实现光敏器件的控制，因此，在设置薄膜晶体管时无需压缩光敏器件的设置空间，从而光敏器件的有效感光面积可以增大，进而可以增强指纹识别传感器产生的光电流信号，提高了指纹识别的准确度。
图7示出了本发明一实施例提供的一种指纹识别传感器的制备方法的步骤流程图，该方法可以包括以下步骤：
步骤701：提供衬底基板；衬底基板包括在垂直于衬底基板的方向(即厚度方向)上贯穿衬底基板的导电结构。
在本发明实施例提供的指纹识别传感器的制备方法中，可以通过激光打孔等方式，沿垂直于衬底基板10的厚度方向，在衬底基板10上形成通孔，然后可以在通孔中电铸导电材料，例如铜金属等，从而可以获得在衬底基板10的厚度方向上贯穿衬底基板10的导电结构11，也即获得具有该导电结构11的衬底基板10，如图8所示。当然，也可以直接提供具有该导电结构11的衬底基板成品，本发明实施例对此不作具体限定。
例如，衬底基板10的导电结构11可以包括分立的第一导电子结构111和 第二导电子结构112，第一导电子结构111和第二导电子结构112在衬底基板10的厚度方向上均贯穿衬底基板10。
步骤702：在衬底基板的与第一表面相背的第二表面上形成薄膜晶体管，即在衬底基板的一侧形成薄膜晶体管。
在本发明实施例中，衬底基板10可以包括相背的第一表面S1和第二表面S2，衬底基板10的第一表面S1可以用于制备光敏器件30，衬底基板10的第二表面S2可以用于制备薄膜晶体管20。
例如，本步骤具体可以通过下述子步骤(1)至(5)实现，包括：
子步骤(1)：在衬底基板10的与第一表面S1相背的第二表面S2上形成栅极21。
例如，子步骤(1)具体可以包括：在衬底基板10的与第一表面S1相背的第二表面S2上同层形成栅极21和第三电极40。第三电极40与第二导电子结构112连接，如图9所示。第三电极40可以被配置为通过第二导电子结构112及第一搭接电极向光敏器件输入工作电压，第三电极40即为光敏器件工作电压的输入端，第一搭接电极属于光敏器件30。栅极21和第三电极40可以通过一次光刻工艺同层形成，从而可以减少指纹识别传感器的制备流程。
例如，栅极21的材料可以包括Mo、Al、Cu、Ti中的至少一种，本发明实施例对此不作具体限定。
子步骤(2)：形成覆盖栅极的栅极绝缘层。
子步骤(3)：在栅极绝缘层上形成有源层。
例如，可以通过沉积工艺依次形成栅极绝缘材料层和有源材料层，然后可以通过第一次光刻工艺，对有源材料层进行湿刻，获得有源层23，之后可以通过第二次光刻工艺，对栅极绝缘材料层进行干刻，获得延伸至第一导电子结构111的第三过孔221，从而获得栅极绝缘层22，如图10所示。
例如，栅极21的材料可以包括SiO、SiON、SiN中的至少一种，有源层23的材料可以包括a-Si、IGZO、IZO、IGZXO、IGZYO中的至少一种，本发明实施例对此不作具体限定。
子步骤(4)：同层形成源极和漏极；源极和漏极分别与有源层连接；源极或漏极通过栅极绝缘层上的第三过孔与衬底基板的第一导电子结构连接。
例如，参照图11，可以通过一次光刻工艺，同层形成源极24和漏极25，在具体应用时，源极24和漏极25可以位置互换，本发明实施例对此不作具体 限定。其中，源极24和漏极25分别与有源层23连接，且源极24或漏极25通过栅极绝缘层22上的第三过孔221与第一导电子结构111连接。
例如，源极24和漏极25的材料可以包括Mo、Al、Cu、Nd、Ti中的至少一种，本发明实施例对此不作具体限定。
子步骤(5)：形成钝化层；钝化层覆盖源极、漏极、有源层及栅极绝缘层。
例如，参照图12，可以通过沉积工艺，形成覆盖源极24、漏极25、有源层23及栅极绝缘层22的钝化层26。
例如，钝化层26的材料可以包括SiOx、SiNx、SiON、AlOx中的至少一种，本发明实施例对此不作具体限定。
至此，可以在衬底基板10的第二表面S2上形成薄膜晶体管20。
步骤703：在衬底基板的第一表面上形成光敏器件，即在衬底基板远离薄膜晶体管的一侧形成光敏器件；薄膜晶体管、衬底基板和光敏器件沿衬底基板的厚度方向层叠设置；光敏器件通过衬底基板的导电结构与薄膜晶体管连接。
在本发明实施例中，本步骤具体可以通过下述子步骤(6)至(10)实现，包括：
子步骤(6)：在衬底基板的第一表面上形成第一电极；第一电极与第一导电子结构连接。
在一些示例中，可以通过沉积工艺和光刻工艺，在衬底基板10的第一表面S1上形成第一电极31，其中，第一电极31可以与第一导电子结构111连接。
在一些示例中，指纹识别传感器还可以包括第二搭接电极01，相应的，可以通过沉积工艺和光刻工艺，在衬底基板10的第一表面S1上同层形成第一电极31和第二搭接电极01，如图13所示。其中，第二搭接电极01可以用于搭接第三电极40和光敏器件30的第一搭接电极。
例如，第一电极31和第二搭接电极01的材料可以包括Mo、Al、Cu、Nd、Ti中的至少一种，本发明实施例对此不作具体限定。
由于薄膜晶体管20和光敏器件30可以分别设置在衬底基板10相背的两个表面，而不在衬底基板10的同侧，因此，在氢离子环境下沉积形成光敏器件30的光敏层时，衬底基板10可以起到天然的保护作用，从而避免薄膜晶体管20的有源层被氢离子导体化。
子步骤(7)：在第一电极远离衬底基板的一侧形成光敏层。
子步骤(8)：在光敏层远离第一电极的一侧形成第二电极。
在一些示例中，可以通过沉积工艺依次形成光敏材料层和第二电极材料层，然后可以通过第一次光刻工艺，对第二电极材料层进行湿刻，之后可以通过第二次光刻工艺，例如RIE(Reactive Ion Etching，反应离子刻蚀)工艺，对光敏材料层进行干刻，获得光敏层32，进而可以通过第三次光刻工艺，对一次光刻后的第二电极材料层再进行湿刻，从而可以获得第二电极33，如图14所示。其中，参照图14，第二电极33的面积可以小于光敏层32的面积，从而可以降低光敏器件30边缘的漏电流，进而能够提高光敏器件30的灵敏度。
例如，第二电极33的材料可以为ITO等，本发明实施例对此不作具体限定。
子步骤(9)：形成保护层；保护层覆盖第一电极、光敏层、第二电极及衬底基板的第一表面。
在一些示例中，可以通过沉积工艺，形成覆盖第一电极31、光敏层32、第二电极33及衬底基板10的第一表面S1的保护层34，然后可以通过光刻工艺，在保护层34对应第二电极33的位置处形成第一过孔341，以及在保护层34对应第二导电子结构112的位置处形成第二过孔342，如图15所示。
例如，保护层34的材料可以包括SiO、SiN、SiON中的至少一种，本发明实施例对此不作具体限定。
子步骤(10)：形成第一搭接电极；第一搭接电极位于保护层远离衬底基板的一侧；第一搭接电极通过保护层的第一过孔与第二电极连接，第一搭接电极通过保护层的第二过孔与第二导电子结构连接。
例如，可以在保护层34远离衬底基板的一侧第一搭接电极35，如图5所示，第一搭接电极35可以通过保护层34的第一过孔341与第二电极33连接，第一搭接电极35还可以通过保护层34的第二过孔342与第二导电子结构112连接，或者通过保护层34的第二过孔342、以及第二搭接电极01与第二导电子结构112连接。
在一些示例中，第一搭接电极35的材料可以为透明电极材料，例如ITO，从而被第一搭接电极35遮挡的光敏器件部分能够进行有效感光，进而增大了指纹识别传感器的有效感光面积。
在一些示例中，第二电极33的材料与第一搭接电极35的材料可以为同种材料，例如均为ITO，本发明实施例对此不作具体限定。由于同种材料之间的匹配度更高，噪声更低，因此，能够降低光敏器件30的暗电流，进而提高了 光敏器件30的灵敏度。
至此，可以在衬底基板10的第一表面S1上形成光敏器件30。在衬底基板10相背的两个表面分别形成薄膜晶体管20和光敏器件30后，即可获得指纹识别传感器。
需要说明的是，在实际应用中，步骤702和步骤703的实现顺序可以互换。另外，上述仅提供了各个结构的一种或多种形成方式，以及一种或多种可选的材料，可以理解的是，在具体应用时，还可以采用其他方式或材料形成各个结构，本发明实施例对此不作具体限定。
在本发明实施例提供的指纹识别传感器的制备方法中，首先可以提供一衬底基板，该衬底基板包括在衬底基板的厚度方向上贯穿衬底基板的导电结构，然后可以在衬底基板的第一表面上形成光敏器件，以及在衬底基板的与第一表面相背的第二表面上形成薄膜晶体管。其中，薄膜晶体管、衬底基板和光敏器件沿衬底基板的厚度方向层叠设置，光敏器件可以通过衬底基板的导电结构与薄膜晶体管连接。在本发明实施例中，可以在衬底基板相背的两个表面分别设置薄膜晶体管和光敏器件，且二者可以通过衬底基板的导电结构电连接，以实现光敏器件的控制，因此，在设置薄膜晶体管时无需压缩光敏器件的设置空间，从而光敏器件的有效感光面积可以增大，进而可以增强指纹识别传感器产生的光电流信号，提高了指纹识别的准确度。
本发明一实施例还公开一种显示装置，包括上述指纹识别传感器。
在本发明实施例中，显示装置中的指纹识别传感器可以包括衬底基板、薄膜晶体管和光敏器件，薄膜晶体管、衬底基板和光敏器件沿衬底基板的厚度方向层叠设置。其中，衬底基板包括在衬底基板的厚度方向上贯穿衬底基板的导电结构，光敏器件可以通过衬底基板的导电结构与薄膜晶体管连接。在本发明实施例中，薄膜晶体管、衬底基板和光敏器件沿衬底基板的厚度方向层叠设置，也即是薄膜晶体管和光敏器件可以分别设置在衬底基板相背的两个表面，且二者可以通过衬底基板的导电结构电连接，以实现光敏器件的控制，因此，在设置薄膜晶体管时无需压缩光敏器件的设置空间，从而光敏器件的有效感光面积可以增大，进而可以增强指纹识别传感器产生的光电流信号，提高了指纹识别的准确度。
对于前述的各方法实施例，为了简单描述，故将其都表述为一系列的动作组合，但是本领域技术人员应该知悉，本发明并不受所描述的动作顺序的限制， 因为依据本发明，某些步骤可以采用其他顺序或者同时进行。其次，本领域技术人员也应该知悉，说明书中所描述的实施例均属于优选实施例，所涉及的动作和模块并不一定是本发明所必须的。
(1)本公开实施例附图中，只涉及到与本公开实施例涉及到的结构，其他结构可参考通常设计。
(2)在不冲突的情况下，本公开同一实施例及不同实施例中的特征可以相互组合。
以上，仅为本公开的具体实施方式，但本公开的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本公开揭露的技术范围内，可轻易想到变化或替换，都应涵盖在本公开的保护范围之内。因此，本公开的保护范围应以权利要求的保护范围为准。

Claims (18)

  1. 一种指纹识别传感器，包括：
    衬底基板；
    薄膜晶体管，位于所述衬底基板的一侧；以及
    光敏器件，位于所述衬底基板远离所述薄膜晶体管的一侧，
    其中，所述薄膜晶体管、所述衬底基板和所述光敏器件沿垂直于所述衬底基板的厚度方向依次层叠设置，所述衬底基板包括在垂直于所述衬底基板的厚度方向上贯穿所述衬底基板的导电结构，所述光敏器件通过所述导电结构与所述薄膜晶体管连接。
  2. 根据权利要求1所述的指纹识别传感器，其中，所述导电结构包括分立的第一导电子结构和第二导电子结构，所述第一导电子结构和所述第二导电子结构在所述衬底基板的厚度方向上均贯穿所述衬底基板；
    所述光敏器件包括：位于所述衬底基板的第一表面上的第一电极；位于所述第一电极远离所述衬底基板的一侧的光敏层；以及位于所述光敏层远离所述第一电极的一侧的第二电极，所述第一电极与所述第一导电子结构连接，所述第二电极被配置为与所述第二导电子结构电性相连。
  3. 根据权利要求2所述的指纹识别传感器，其中，所述光敏器件包括光敏层，所述薄膜晶体管包括有源层，所述光敏层在所述衬底基板上的正投影与所述有源层在所述衬底基板上的正投影交叠。
  4. 根据权利要求3所述的指纹识别传感器，其中，所述光敏层在所述衬底基板上的正投影覆盖所述有源层在所述衬底基板上的正投影。
  5. 根据权利要求2-4中任一项所述的指纹识别传感器，其中，所述光敏器件还包括：
    保护层，覆盖所述第一电极、所述光敏层、所述第二电极和所述衬底基板的第一表面；以及
    第一搭接电极，位于所述保护层远离所述光敏层的一侧，
    其中，所述保护层包括第一过孔和第二过孔，所述第一搭接电极通过所述保护层中的所述第一过孔与所述第二电极连接，所述第一搭接电极通过所述保护层中的第二过孔与所述第二导电子结构连接。
  6. 根据权利要求5所述的指纹识别传感器，还包括：
    第三电极，位于所述衬底基板的与所述第一表面相背的第二表面上，且与所述第二导电子结构连接；所述第三电极被配置为通过所述第二导电子结构及所述第一搭接电极向所述光敏器件输入工作电压。
  7. 根据权利要求5所述的指纹识别传感器，其中，所述第一搭接电极的材料为透明电极材料。
  8. 根据权利要求3或4所述的指纹识别传感器，其中，所述薄膜晶体管还包括：
    栅极，位于所述衬底基板远离所述光敏器件的一侧的表面上；栅极绝缘层，位于所述栅极远离所述衬底基板的一侧，且覆盖所述栅极；以及源极和漏极，其中，所述有源层位于所述栅极绝缘层远离所述栅极的一侧，所述源极和漏极位于所述栅极绝缘层远离所述有源层的一侧，所述源极和所述漏极分别与所述有源层相连，所述栅极绝缘层包括第三过孔，所述源极或所述漏极通过所述栅极绝缘层中第三过孔与所述衬底基板的第一导电子结构连接。
  9. 根据权利要求8所述的指纹识别传感器，还包括：
    钝化层，位于所述源极和所述漏极远离所述有源层的一侧，且覆盖所述源极、所述漏极、所述有源层及所述栅极绝缘层。
  10. 一种指纹识别传感器的制备方法，包括：
    提供衬底基板，所述衬底基板包括在垂直于所述衬底基板的厚度方向上贯穿所述衬底基板的导电结构；
    在衬底基板的一侧形成薄膜晶体管；以及
    在衬底基板远离所述薄膜晶体管的一侧形成光敏器件，
    其中，所述薄膜晶体管、所述衬底基板和所述光敏器件沿垂直于所述衬底基板的厚度方向依次层叠设置，所述光敏器件通过所述导电结构与所述薄膜晶体管连接。
  11. 根据权利要求10所述的制备方法，其中，所述导电结构包括分立的第一导电子结构和第二导电子结构，所述第一导电子结构和所述第二导电子结构在所述衬底基板的厚度方向上均贯穿所述衬底基板；
    在衬底基板远离所述薄膜晶体管的一侧形成光敏器件包括：
    在所述衬底基板的第一表面上形成第一电极；
    在所述第一电极远离所述衬底基板的一侧形成光敏层；以及
    在所述光敏层远离所述第一电极的一侧形成第二电极，
    其中，所述第一电极与所述第一导电子结构连接，所述第二电极被配置为与所述第二导电子结构电性相连。
  12. 根据权利要求11所述的制备方法，其中，在衬底基板远离所述薄膜晶体管的一侧形成光敏器件还包括：
    在所述第二电极远离所述光敏层的一侧形成保护层，所述保护层覆盖所述第一电极、所述光敏层、所述第二电极和所述衬底基板的第一表面；以及
    在所述保护层远离光敏层的一侧形成第一搭接电极，所述第一搭接电极位于所述保护层远离所述光敏层的一侧，
    其中，所述保护层包括第一过孔和第二过孔，所述第一搭接电极通过所述保护层中的所述第一过孔与所述第二电极连接，所述第一搭接电极通过所述保护层中的第二过孔与所述第二导电子结构连接。
  13. 根据权利要求12所述的制备方法，还包括：
    在所述衬底基板的与所述第一表面相背的第二表面上形成第三电极，
    其中，所述第三电极与所述第二导电子结构连接；所述第三电极被配置为通过所述第二导电子结构及所述第一搭接电极向所述光敏器件输入工作电压。
  14. 根据权利要求11-13中任一项所述的制备方法，其中，在衬底基板的一侧形成薄膜晶体管包括：
    在衬底基板的一侧形成栅极；
    在所述栅极远离所述衬底基板的一侧形成栅极绝缘层，所述栅极绝缘层覆盖所述栅极；
    在所述栅极绝缘层远离所述栅极的一侧形成有源层；以及
    在所述有源层远离所述栅极绝缘层的一侧形成源极和漏极，
    其中，所述源极和所述漏极分别与所述有源层相连，所述栅极绝缘层包括第三过孔，所述源极或所述漏极通过所述栅极绝缘层中第三过孔与所述衬底基板的第一导电子结构连接。
  15. 根据权利要求14所述的制备方法，其中，所述光敏层在所述衬底基板上的正投影与所述有源层在所述衬底基板上的正投影交叠。
  16. 根据权利要求15所述的制备方法，其中，所述光敏层在所述衬底基板上的正投影覆盖所述有源层在所述衬底基板上的正投影。
  17. 根据权利要求14-16中任一项所述的制备方法，还包括：
    在所述源极和所述漏极远离所述有源层的一侧形成钝化层，
    其中，所述钝化层覆盖所述源极、所述漏极、所述有源层及所述栅极绝缘层。
  18. 一种显示装置，包括权利要求1-9任一项所述的指纹识别传感器。
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CN111192889A (zh) * 2020-01-07 2020-05-22 京东方科技集团股份有限公司 光检测模块及其制备方法、光检测基板
CN111563419A (zh) * 2020-04-14 2020-08-21 京东方科技集团股份有限公司 一种指纹识别单元、显示面板、以及显示装置
CN111682037B (zh) * 2020-05-19 2023-12-05 京东方科技集团股份有限公司 光电探测器件、显示基板及显示装置
CN113741736B (zh) * 2020-05-29 2023-12-08 京东方科技集团股份有限公司 一种传感器、显示面板、显示装置
CN113917749B (zh) * 2021-10-18 2023-10-13 京东方科技集团股份有限公司 阵列基板，显示面板，显示装置及阵列基板的制作方法
CN115394789A (zh) * 2022-08-24 2022-11-25 京东方科技集团股份有限公司 显示基板及其制备方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105095872A (zh) * 2015-07-29 2015-11-25 京东方科技集团股份有限公司 一种基板及其制备方法、指纹识别传感器、指纹识别装置
CN105975963A (zh) * 2016-06-30 2016-09-28 京东方科技集团股份有限公司 一种指纹识别基板及其制备方法、显示面板和显示装置
CN106055162A (zh) * 2016-06-30 2016-10-26 京东方科技集团股份有限公司 显示组件和显示装置
CN106684202A (zh) * 2017-01-04 2017-05-17 京东方科技集团股份有限公司 一种感光组件、指纹识别面板及装置
CN107065274A (zh) * 2017-06-19 2017-08-18 上海天马微电子有限公司 阵列基板、显示面板及显示装置
CN109994498A (zh) * 2019-04-09 2019-07-09 京东方科技集团股份有限公司 一种指纹识别传感器及其制备方法、以及显示装置

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106129069B (zh) * 2016-07-26 2019-11-05 京东方科技集团股份有限公司 一种指纹识别器、其制作方法及显示装置
CN107248518B (zh) * 2017-05-26 2020-04-17 京东方科技集团股份有限公司 光电传感器及其制作方法、显示装置
CN108987455B (zh) * 2018-09-14 2021-01-22 京东方科技集团股份有限公司 用于显示面板的阵列基板、显示面板

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105095872A (zh) * 2015-07-29 2015-11-25 京东方科技集团股份有限公司 一种基板及其制备方法、指纹识别传感器、指纹识别装置
CN105975963A (zh) * 2016-06-30 2016-09-28 京东方科技集团股份有限公司 一种指纹识别基板及其制备方法、显示面板和显示装置
CN106055162A (zh) * 2016-06-30 2016-10-26 京东方科技集团股份有限公司 显示组件和显示装置
CN106684202A (zh) * 2017-01-04 2017-05-17 京东方科技集团股份有限公司 一种感光组件、指纹识别面板及装置
CN107065274A (zh) * 2017-06-19 2017-08-18 上海天马微电子有限公司 阵列基板、显示面板及显示装置
CN109994498A (zh) * 2019-04-09 2019-07-09 京东方科技集团股份有限公司 一种指纹识别传感器及其制备方法、以及显示装置

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