WO2020118499A1

WO2020118499A1 - Optical sensor and forming method therefor

Info

Publication number: WO2020118499A1
Application number: PCT/CN2018/120168
Authority: WO
Inventors: 凌严; 朱虹
Original assignee: 上海箩箕技术有限公司
Priority date: 2018-12-11
Filing date: 2018-12-11
Publication date: 2020-06-18

Abstract

An optical sensor and a forming method therefor. The optical sensor comprises: a substrate (200); a fingerprint sensing circuit layer (210) located on the substrate (200), the fingerprint sensing circuit layer (210) comprising a pixel region (A) and a first binding region (B), wherein the pixel region (A) comprises a plurality of columns of photosensitive pixel units (a1), one or more columns of non-photosensitive pixel units (a2) located at the sides of the plurality of columns of photosensitive pixel units (a1), a first data line (2101) connected to each column of photosensitive pixel units (a1), and a second data line (2102) connected to each column of non-photosensitive pixel units (a2), and the first binding region (B) comprises a plurality of first binding pins (2201) respectively connected to the first data lines (2101), second binding pins (2202) located at the sides of the plurality of first binding pins (2201) and connected to the second data lines (2102), and first pseudo binding pins (2203) between the plurality of first binding pins (2201) and second binding pins (2202); and an anisotropic conductive layer (300) located on the first binding region (B). The performance of the optical sensor is improved.

Description

Optical sensor and its forming method

Technical field

The invention relates to the field of sensors, in particular to an optical sensor and a method of forming the same.

Background technique

The optical sensor is a large-area planar imaging device, which is composed of a pixel cell array, drive lines, signal readout lines, and the like. The optical signal with image information is directly projected to each pixel unit of the imaging surface of the sensor, which is absorbed and imaged by the pixel unit of the sensor. Since the light is not focused through the lens or fiber, it is the same size, without scaling, so it will have better imaging quality; at the same time, the imaging device is also thinner and lighter, so it has been widely used in various fields.

For example, optical sensors used in fingerprint imaging, document scanning and other fields. Each pixel unit is composed of a switching device and a photoelectric device. Visible light is converted into electronic signals by photoelectric devices in each pixel unit of the optical sensor and stored. The system controller controls the driving chip on the driving unit to control the driving line on the optical sensor, and then controls the row-by-row opening of the pixel unit array; at the same time, the system controller controls the signal reading unit on the signal acquisition unit to pass through the optical sensor The signal line reads the electronic signal of the row that is turned on in the pixel cell array, and then performs amplification, analog-to-digital conversion, and storage. Finally, a digital grayscale image directly related to the surface characteristics of the illuminated object is realized.

However, the performance of existing optical sensors needs to be improved.

Summary of the invention

The problem solved by the present invention is to provide an optical sensor and a forming method thereof to improve the performance of the optical sensor.

To solve the above problem, the present invention provides an optical sensor, including: a substrate; a fingerprint sensing circuit layer on the substrate, the fingerprint sensing circuit layer including a pixel area and a first binding area located on the side of the pixel area; The pixel area of the fingerprint sensing circuit layer includes: a plurality of columns of photosensitive pixel units; one or more columns of non-photosensitive pixel units, the non-photosensitive pixel units are located on the sides of the plurality of columns of photosensitive pixel units; A first data line; a second data line connected to each column of non-photosensitive pixel units; the first binding area of the fingerprint sensing circuit layer includes: a plurality of first binding pins, the first binding pins are respectively Connected to the first data line; the second binding pin located on the side of the plurality of first binding pins, and the second binding pin is connected to the second data line; located at the plurality of first binding pins And a first pseudo-binding pin between the second binding pin; an anisotropic conductive layer on the first binding area of the fingerprint sensing circuit layer.

Optionally, the conductivity of the anisotropic conductive layer perpendicular to the surface of the first binding area is greater than that parallel to the surface of the first binding area.

Optionally, the first binding pin and the second binding pin are parallel and parallel to the first pseudo binding pin.

Optionally, the line width of the first bonding pin is equal to the line width of the second bonding pin and equal to the line width of the first pseudo bonding pin.

Optionally, the spacing between the adjacent first binding pin and the first pseudo-binding pin, the spacing between the adjacent second binding pin and the first pseudo-binding pin, and any The spacing between adjacent first bonding pins is equal.

Optionally, for the second binding pins on the side of the plurality of first binding pins, the number of second binding pins is multiple, and the second binding pins are respectively connected to the second data lines; The spacing between any adjacent first bonding pins is equal to the spacing between any adjacent second bonding pins.

Optionally, for the first pseudo binding pins on the side of the plurality of first binding pins, the number of the first pseudo binding pins is multiple.

Optionally, the spacing between the adjacent first binding pins and the first pseudo-binding pins is equal to the spacing between any adjacent first binding pins.

Optionally, the first pseudo-bonded pins are arranged at equal intervals; the distance between any adjacent first pseudo-bonded pins is 10 μm to 400 μm.

Optionally, for the first pseudo binding pins on the side of the plurality of first binding pins, the number of first pseudo binding pins is greater than or equal to 5.

Optionally, for the first pseudo binding pins on the side of the plurality of first binding pins, the number of the first pseudo binding pins is one.

Optionally, the non-photosensitive pixel units are located on both sides of the columns of photosensitive pixels; the second binding pins are located on both sides of the first binding pins; There is a first pseudo binding pin between the second binding pin on one side of the binding pin and the plurality of first binding pins, and the second on the other side of the first binding pins There is a first pseudo-binding pin between the binding pin and the plurality of first binding pins.

Optionally, the method further includes: a signal readout flexible circuit, the signal readout flexible circuit includes a second binding area, the second binding area is opposite to the first binding area, and the anisotropic conductive layer Located between the first binding area and the second binding area; the second binding area includes: a plurality of third binding pins, the third binding pins are opposite to the first binding pins, each third The binding pins and the first binding pins are electrically connected in one-to-one correspondence with the anisotropic conductive layer; the fourth binding pin located on the side of the plurality of third binding pins, the fourth binding pin The foot is opposite to the second binding pin, and the fourth binding pin is electrically connected to the second binding pin through an anisotropic conductive layer; it is located between the third binding pins and the fourth binding pin The second pseudo-binding pin between the pins is opposite to the first pseudo-binding pin.

The invention also provides a method for forming an optical sensor according to any one of the above, comprising: providing a substrate; forming a fingerprint sensing circuit layer on the substrate, the fingerprint sensing circuit layer including a pixel area and a third portion located on the side of the pixel area A binding area; the pixel area of the fingerprint sensing circuit layer includes: a plurality of columns of photosensitive pixel units; one or more rows of non-photosensitive pixel units, the non-photosensitive pixel units are located on the sides of the plurality of rows of photosensitive pixel units; and each A first data line connected to each column of photosensitive pixel units; a second data line connected to each column of non-photosensitive pixel units; the first binding area of the fingerprint sensing circuit layer includes: a plurality of first binding pins, The first binding pins are respectively connected to the first data line; the second binding pins located at the side of the plurality of first binding pins, and the second binding pins are connected to the second data line; located at the A first pseudo-binding pin between the first and second binding pins; an anisotropic conductive layer is formed on the first binding area of the fingerprint sensing circuit layer.

Optionally, the method further includes: providing a signal readout flexible circuit, the signal readout flexible circuit includes a second binding area, and the second binding area includes: a plurality of third binding pins located on the plurality of The fourth binding pin on the side of the three binding pins; the second pseudo binding pin between the third binding pins and the fourth binding pin; the signal is read out flexibly The circuit is bonded to the anisotropic conductive layer, the anisotropic conductive layer is located between the first binding area and the second binding area, and the second binding area is opposite to the first binding area , The third binding pin is opposite to the first binding pin, the fourth binding pin is opposite to the second binding pin, and the second pseudo binding pin is opposite to the first pseudo binding pin. The three binding pins and the first binding pins are electrically connected to each other through an anisotropic conductive layer, and the fourth binding pin is electrically connected to the second binding pins through an anisotropic conductive layer.

Compared with the prior art, the technical solution of the present invention has the following advantages:

In the optical sensor provided by the technical solution of the present invention, a first pseudo binding pin is provided between the plurality of first binding pins and the second binding pin, so that the first binding pin and the second binding pin The distance between the fixed pins increases. The first pseudo binding pin is not electrically connected. Even when strong light is irradiated to the photosensitive pixel unit and the signal value output by the first data line is large, since the distance between the first bonding pin and the second bonding pin increases, they are adjacent The electric field between the first data line and the second data line is not too great. In this way, the signal of the first data line is prevented from leaking to the second data line through the anisotropic conductive layer, then the signal actually output by the second data line is the background signal value, and the signal of the second data line can be used to reduce electronic noise. In summary, the performance of the optical sensor is improved.

Secondly, the distance between the first and second bonding pins is increased by setting the placement of the first pseudo-bonding pins, so that the density of the bonding pins is kept consistent and the anisotropic conductive layer is made When pressing with the first binding area, the force is uniform everywhere, which is conducive to the pressing effect of the anisotropic conductive layer and the first binding area, and improves the bonding of the anisotropic conductive layer and the first binding area Performance and conductive effect.

BRIEF DESCRIPTION

Figure 1 is a schematic structural view of an optical sensor;

Figure 2 is a top view of Figure 1;

3 to 7 are schematic structural diagrams of an optical sensor formation process in an embodiment of the invention.

detailed description

As described in the background art, the performance of existing optical sensors needs to be improved.

An optical sensor, with reference to FIGS. 1 and 2, includes: a substrate 100; a fingerprint sensing circuit layer 110 on the substrate 100. The fingerprint sensing circuit layer 110 includes a pixel zone Z1 and a binding zone Z2; the pixel zone Z1 includes : Several columns of photosensitive pixel units 110a; one or more columns of non-photosensitive pixel units 110b, the non-photosensitive pixel units 110b are located at the sides of the several columns of photosensitive pixel units 110a; a first data line 1101 connected to each column of photosensitive pixel units 110a ; The second data line 1102 connected to each column of non-photosensitive pixel units 110b; the binding zone Z2 includes: a number of first binding pins (not shown), the first binding pins are respectively connected to the first data line 1101 ; A second binding pin (not shown) located on the side of several first binding pins, the second binding pin is connected to the second data line 1102; an anisotropy located on the first binding zone Z2 Conductive layer 120; the signal readout flexible circuit 130 on the anisotropic conductive layer 120.

The only difference between the non-photosensitive pixel unit 110b and the photosensitive pixel unit 110a is that the non-photosensitive pixel unit 110b is not photosensitive, and the photosensitive pixel unit 110a is photosensitive.

The second data line 1102 is connected to the non-photosensitive pixel unit 110b. Since the non-photosensitive pixel unit 110b is not photosensitive, the output value of the second data line 1102 is maintained at a background signal value at any time. During image acquisition, power fluctuations or external electromagnetic waves interfere with the optical sensor, and the generated electronic noise will be included in this background signal value, and the interference of the non-photosensitive pixel unit 110b and the photosensitive pixel unit 110a is synchronized The size is basically the same. Therefore, when no light is incident on the optical sensor, the signal value output by the first data line 1101 and the signal value output by the second data line 1102 are substantially the same. When light is irradiated to the photosensitive pixel unit 110a, the second data line 1102 is used to collect real-time electronic noise of the optical sensor, and the signal value output by each first data line 1101 minus part or all of the second data line 1102 outputs a background signal The average value of the values can eliminate most of the electronic noise of the image and improve the image effect.

In the first binding zone Z2, the anisotropic conductive layer 120 bonds the signal readout flexible circuit 130 to the binding zone Z2 of the fingerprint sensing circuit layer 110. The anisotropic conductive layer 120 is also used for conducting electricity in a direction perpendicular to the surface of the substrate 100, and for electrical insulation in a direction parallel to the surface of the substrate 100.

The conductivity of the anisotropic conductive layer 120 perpendicular to the surface of the bonding zone Z2 is <30 ohms/bonded pin area, that is, the longitudinal on-resistance of the anisotropic conductive layer 120 on each bonded pin< 30 ohms; the conductivity of the anisotropic conductive layer 120 parallel to the surface of the bonding zone Z2 is >10 ⁸ ohms/the distance between adjacent bonding pins, that is, the anisotropic conduction between any adjacent bonding pins The lateral on-resistance of layer 120 is >10 ⁸ ohms.

However, the anisotropic conductive layer 120 in a direction parallel to the surface of the substrate 100 is not an absolute insulator, anisotropic conductive layer 120 in a direction parallel to the surface of the substrate 100 has certain conductivity (typically above ¹⁰⁸ Ohms) . Secondly, the spacing between the first and second bonding pins in the bonding zone Z2, the line width of the first bonding pin, and the line width of the second bonding pin are smaller ( Generally less than 100um), so that the area of the binding zone Z2 is small, improving the integration of the optical sensor.

On this basis, when stronger light is irradiated to the photosensitive pixel unit 110a, the signal value output by the second data line 1102 is larger, and the potential of the second data line 1102 is significantly different from the potential of the first data line 1101. The electric field between the adjacent first data line 1101 and the second data line 1102 is relatively strong. Therefore, the signal of the adjacent first data line 1101 will leak to the second data line 1102 through the anisotropic conductive layer 120, which causes the signal actually output by the second data line 1102 to become larger. At this time, the actual output of the second data line 1102 The signal will include signals other than the background signal value, so the signal of the second data line 1102 cannot be used to reduce electronic noise in real time.

On this basis, the present invention provides an optical sensor, including: a substrate; a fingerprint sensing circuit layer on the substrate, the fingerprint sensing circuit layer includes a pixel area and a first binding area; the pixel area includes: a plurality of columns of photosensitive pixels Unit; one or more columns of non-photosensitive pixel units, the non-photosensitive pixel units are located on the sides of the plurality of columns of photosensitive pixel units; the first data lines respectively connected to each column of photosensitive pixel units; respectively connected to each column of non-photosensitive pixel units The second binding line; the first binding area includes: a number of first binding pins, the first binding pins are respectively connected to the first data line; the second binding is located on the side of the number of first binding pins Pin, the second binding pin is connected to the second data line; the first pseudo binding pin is located between several first binding pins and the second binding pin; the one located on the first binding area Anisotropic conductive layer. The performance of the optical sensor is improved.

In order to make the above objects, features and advantages of the present invention more obvious and understandable, specific embodiments of the present invention will be described in detail below with reference to the drawings.

3 to 6 are structural schematic diagrams of a semiconductor device forming process in an embodiment of the invention.

With reference to FIGS. 3 and 4, FIG. 4 is a top view of FIG. 3, and a substrate 200 is provided.

The substrate 200 is a transparent substrate. The transparent substrate includes a glass substrate or a plastic substrate, and the plastic substrate includes a PI or PET substrate.

With continued reference to FIGS. 3 and 4, a fingerprint sensing circuit layer 210 is formed on the substrate 200. The fingerprint sensing circuit layer 210 includes a pixel area A and a first binding area B located on the side of the pixel area A; The pixel area A of the measurement circuit layer 210 includes: a plurality of columns of photosensitive pixel units a1; one or more columns of non-photosensitive pixel units a2, and the non-photosensitive pixel units a2 are located at the sides of the plurality of columns of photosensitive pixel units a1; The first data line 2101 connected to the unit a1 respectively; the second data line 2102 connected to each column of non-photosensitive pixel units a2; the first binding area B of the fingerprint sensing circuit layer 210 includes: a plurality of first bindings The pin 2201 and the first binding pin 2201 are respectively connected to the first data line 2101; the second binding pin 2202 located on the side of the first binding pins 2201 and the second binding pin 2202 are The second data line 2102 is connected; the first pseudo binding pin 2203 located between the first binding pins 2201 and the second binding pins 2202.

The photosensitive pixel unit a1 includes: a photosensitive device and a first switching device. The first switching device includes at least one transistor. The photosensitive device includes a photodiode.

The non-photosensitive pixel unit a2 and the photosensitive pixel unit a1 are formed in a set of processes. The non-photosensitive pixel unit a2 includes: a non-photosensitive device and a second switching device. The second switching device includes at least one transistor.

In one embodiment, the non-photosensitive device includes a photodiode covered with a light blocking layer, the light blocking layer is used to block light from irradiating the non-photosensitive device, and the material of the light blocking layer includes metal and black organic matter.

In this embodiment, the column direction of the photosensitive pixel units a1 in each column is parallel to the column direction of the non-photosensitive pixel units a2 in each column.

The plurality of photosensitive pixel units a1 form a photosensitive pixel unit array of N rows*M columns, N is an integer greater than or equal to 1, and M is an integer greater than or equal to 1.

The pixel area A of the fingerprint sensing circuit layer 210 further includes: a plurality of rows of driving lines, which are respectively connected to the photosensitive pixel units a1 of each row, specifically, the driving lines of the i-th row are respectively connected to the photosensitive pixels of the i-th row Unit a1 is connected. The driving lines of several rows are used to turn on the photosensitive pixel unit a1 row by row, i is an integer greater than or equal to 1 and less than or equal to N.

The pixel area A of the fingerprint sensing circuit layer 210 includes M columns of first data lines 2101, and the jth column of first data lines 2101 is respectively connected to the jth column of photosensitive pixel unit a1. The first data line 2101 in the jth column is used to read out the output signal of the photosensitive pixel unit a1 in the jth column.

In this embodiment, the non-photosensitive pixel units a2 are respectively located on both sides of the columns of photosensitive pixel units a1. Specifically, one side of the plurality of columns of photosensitive pixel units a1 has N rows*Q columns of non-photosensitive pixel units a2, and the other side of the plurality of columns of photosensitive pixel units a1 has N rows*W columns of non-photosensitive pixel units a2. In other embodiments, the non-photosensitive pixel unit a2 is only located on one side of the columns of photosensitive pixel units a1.

The drive lines are also connected to the non-photosensitive pixel units a2 of each row, specifically, the drive line of the i-th row is connected to the non-photosensitive pixel unit a2 of the i-th row, respectively. The driving line is also used to turn on the non-photosensitive pixel unit a2.

The pixel area A of the fingerprint sensing circuit layer 210 includes one or more columns of second data lines 2102. The number of columns of the second data line 2102 is equal to the number of columns of the non-photosensitive pixel unit a2. A row of second data lines 2102 are respectively connected to a row of non-photosensitive pixel units a2. The second data line 2102 is used to read out the output signal of the non-photosensitive pixel unit a2.

In this embodiment, the second binding pins 2202 are located on both sides of the first binding pins 2201, respectively. There is a first pseudo binding pin 2203 between the second binding pin 2202 on the side of the plurality of first binding pins 2201 and the plurality of first binding pins 2201, and the plurality of first binding There is a first pseudo binding pin 2203 between the second binding pin 2202 on the other side of the pin 2201 and the plurality of first binding pins 2201.

For the second binding pins 2202 on any one of the two sides of the first binding pins 2201, the number of the second binding pins 2202 is multiple or one.

The first pseudo binding pin 2203 and the first data line 2101 are not connected, the first pseudo binding pin 2203 and the first data line 2101 are electrically disconnected, and the first pseudo binding pin 2203 and the second data line 2102 If not connected, the first pseudo binding pin 2203 and the second data line 2102 are electrically disconnected.

In this embodiment, for the first pseudo binding pins 2203 on the side of the first binding pins 2201, the number of the first pseudo binding pins 2203 is multiple. For the first pseudo binding pins 2203 on the other side of the plurality of first binding pins 2201, the number of the first pseudo binding pins 2203 is multiple.

In other embodiments, for the first pseudo binding pins 2203 on the side of the plurality of first binding pins 2201, the number of the first pseudo binding pins 2203 is one, and for the plurality of first bindings The first pseudo-bonded pin 2203 on the other side of the pin 2201, and the number of the first pseudo-bonded pin 2203 is one.

The first binding pin 2201 and the second binding pin 2202 are parallel and parallel to the first pseudo binding pin 2203.

The line width of the first bonding pin 2201 is equal to the line width of the second bonding pin 2202 and equal to the line width of the first pseudo bonding pin 2203.

In this embodiment, the spacing between the adjacent first binding pins 2201 and the first pseudo binding pins 2203, the spacing between any adjacent first binding pins 2201, and any adjacent The spacing between the two binding pins 2202, the spacing between the adjacent first binding pins 2201 and the first pseudo binding pins 2203, the adjacent second binding pins 2202 and the first pseudo binding The spacing between the fixed pins 2203 and the spacing between any adjacent first pseudo-bonded pins 2203 are equal.

In a specific embodiment, the distance between the adjacent first bonding pin 2201 and the first pseudo bonding pin 2203 is 10 μm to 400 μm; the adjacent second bonding pin 2202 and the second The distance between a pseudo-binding pin 2203 is 10 microns to 400 microns.

The first pseudo binding pins 2203 are arranged at equal intervals, and the distance between any adjacent first pseudo binding pins 2203 is 10 μm to 400 μm.

In a specific embodiment, for the first pseudo binding pins 2203 on the side of the plurality of first binding pins 2201, the number of first pseudo binding pins 2203 is greater than or equal to 5. The advantage is that when the distance between the adjacent first pseudo binding pin 2203 and the first binding pin 2201 (less than 50um), and the adjacent first pseudo binding pin 2203 and the second binding lead The spacing between the feet 2202 (less than 50um) and the spacing between the adjacent first pseudo-bonding pins 2203 (less than 50um) are relatively small, and are increased by setting at least five first pseudo-bonding pins 2203 The larger effective insulation distance between the first bonding pin 2201 and the second bonding pin 2202 makes the leakage of the first bonding pin 2201 and the second bonding pin 2202 effectively reduced.

In this embodiment, the distance between the first binding pin 2201 and the second binding pin 2202 is increased by setting the placement of the first pseudo binding pin 2203, so that the density of the binding pins remains consistent, Make the anisotropic conductive layer and the first binding area pressed uniformly at all places, avoiding between the anisotropic conductive layer and the first binding pin 2201, the anisotropic conductive layer and the second binding Air bubbles appear between the pins 2202, thereby facilitating the pressing effect of the anisotropic conductive layer and the first binding area, and improving the adhesion performance and the conductive effect of the anisotropic conductive layer and the first binding area.

With reference to FIGS. 5 and 6, FIG. 6 is a top view of FIG. 5, FIG. 5 is a schematic diagram based on FIG. 3, and FIG. 6 is a schematic diagram based on FIG. 4, the first binding on the fingerprint sensing circuit layer 210 An anisotropic conductive layer 300 is formed on the area B.

The conductivity of the anisotropic conductive layer 300 perpendicular to the surface of the first binding region 2201 is greater than that parallel to the surface of the first binding region 2201.

With continued reference to FIGS. 5 and 6, a signal readout flexible circuit 400 is provided. The signal readout flexible circuit 400 includes a second binding area C, and the second binding area C includes: a number of third binding pins 4011 , A fourth binding pin 4012 located on the side of the third binding pins 4011; a second pseudo located between the third binding pins 4011 and the fourth binding pin 4012 Binding pin 4013; the signal reading flexible circuit 400 is bonded to the anisotropic conductive layer 300, the anisotropic conductive layer 300 is located between the first binding area B and the second binding area C In the meantime, the second binding area C is opposite to the first binding area B, the third binding pin 4011 is opposite to the first binding pin 2201, and the fourth binding pin 4012 is opposite to the second binding pin 2202 is opposite, the second pseudo binding pin 4013 and the first pseudo binding pin 2203 are opposite, and each third binding pin 4011 and each first binding pin 2201 correspond to one to one through the anisotropic conductive layer 300 For sexual connection, the fourth bonding pin 4012 is electrically connected to the second bonding pin 2202 through the anisotropic conductive layer 300.

A signal reading chip is bound to the signal reading flexible circuit 400, that is, the signal reading chip and the signal reading flexible circuit 400 are bound together. In this embodiment, each second pseudo binding pin 4013 is electrically disconnected from the signal readout chip.

In another embodiment, referring to FIG. 7, each second pseudo-bond pin 4013 is electrically connected to the signal readout chip respectively, so that the potential of the second pseudo-bond pin 4013 can be kept stable at all times. Image interference.

If the second pseudo-binding pins 4013 are all floating, external interference factors will be coupled to the second pseudo-binding pins 4013 or the first pseudo-binding pins through the second pseudo-binding pins 4013, thereby generating an image interference.

Correspondingly, this embodiment also provides an optical sensor. Please refer to FIGS. 5 and 6 together, including: a substrate 200; a fingerprint sensing circuit layer 210 on the substrate 200. The fingerprint sensing circuit layer 210 includes a pixel area A and The first binding area B adjacent to the pixel area A; the pixel area A of the fingerprint sensing circuit layer 210 includes: a plurality of columns of photosensitive pixel units a1; one or more columns of non-photosensitive pixel units a2, and the non-photosensitive pixel units a2 are located Side portions of the plurality of columns of photosensitive pixel units a1; a first data line 2101 connected to each column of photosensitive pixel units a1; a second data line 2102 connected to each column of non-photosensitive pixel units a2; the fingerprint sensing circuit layer The first binding area B of 210 includes: a plurality of first binding pins 2201, the first binding pins 2201 are respectively connected to the first data line 2101; Two binding pins 2202, the second binding pin 2202 is connected to the second data line 2102; the first pseudo binding lead between the first binding pins 2201 and the second binding pins 2202 Pin 2203; an anisotropic conductive layer 300 located on the first binding area B of the fingerprint sensing circuit layer 210.

The conductivity of the anisotropic conductive layer 300 perpendicular to the surface of the first bonding area B is greater than that parallel to the surface of the first bonding area B.

In this embodiment, the spacing between the adjacent first binding pins 2201 and the first pseudo binding pins 2203, the spacing between any adjacent first binding pins 2201, the adjacent first The spacing between the binding pin 2201 and the first pseudo binding pin 2203, the spacing between the adjacent second binding pin 2202 and the first pseudo binding pin 2203, and any adjacent first The spacing between the pseudo-binding pins 2203 is equal.

In a specific embodiment, for the first pseudo binding pins 2203 on the side of the plurality of first binding pins 2201, the number of first pseudo binding pins 2203 is greater than or equal to 5.

The optical sensor further includes a signal readout flexible circuit 400, the signal readout flexible circuit 400 includes a second binding area C, the second binding area C is opposite to the first binding area B, and the The anisotropic conductive layer 300 is located between the first binding region B and the second binding region C.

The second binding area C includes: a plurality of third binding pins 4011, the third binding pins 4011 are opposite to the first binding pins 2201, and each third binding pin 4011 is bound to each first binding pin The pins 2201 are electrically connected one-to-one through the anisotropic conductive layer 300; the fourth bonding pin 4012 located on the side of the third bonding pins 4011, the fourth bonding pin 4012 and the second bonding The fixed pin 2202 is opposite, and the fourth bonding pin 4012 is electrically connected to the second bonding pin 2202 through the anisotropic conductive layer 300; it is located between the third bonding pins 4011 and the fourth bonding The second pseudo binding pin 4013 between the pins 4012 is opposite to the first pseudo binding pin 2203.

In this embodiment, the second data line 2102 is connected to the non-photosensitive pixel unit a2. Since the non-photosensitive pixel unit a2 is not photosensitive, the second data line 2102 is used to output the background signal value at any time. During image acquisition, power fluctuations or external electromagnetic waves interfere with the optical sensor, and the generated electronic noise will be included in this background signal value, and the interference of the non-photosensitive pixel unit a2 and the photosensitive pixel unit a1 is synchronized The size is basically the same. When no light is incident on the optical sensor, the signal value output by the first data line 2101 and the signal value output by the second data line 2102 are substantially the same.

Since when the light is irradiated to the photosensitive pixel unit a1, the signal of the first data line 2101 is prevented from leaking to the second data line 2102 through the anisotropic conductive layer 300, then the actual output signal of the second data 2102 line is the background signal value, Therefore, the second data line 2102 can accurately collect the real-time electronic noise of the optical sensor, and the signal value output by each first data line 2101 is subtracted from the average value of part or all of the background signal value output by the second data line 2102, so that Eliminate most of the electronic noise of the image and improve the image effect.

Although the present invention is disclosed as above, the present invention is not limited to this. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

An optical sensor, characterized in that it includes:

Substrate

A fingerprint sensing circuit layer on the substrate, the fingerprint sensing circuit layer includes a pixel area and a first binding area located on the side of the pixel area;

The pixel area of the fingerprint sensing circuit layer includes: a plurality of columns of photosensitive pixel units; one or more columns of non-photosensitive pixel units, the non-photosensitive pixel units are located at the sides of the plurality of columns of photosensitive pixel units; and each column of photosensitive pixel units The first data line connected; the second data line connected to each column of non-photosensitive pixel units;

The first binding area of the fingerprint sensing circuit layer includes: a plurality of first binding pins, the first binding pins are respectively connected to the first data line; A second binding pin, the second binding pin is connected to the second data line; a first pseudo binding pin located between the plurality of first binding pins and the second binding pin;

An anisotropic conductive layer located on the first binding area of the fingerprint sensing circuit layer.
The optical sensor according to claim 1, wherein the conductivity of the anisotropic conductive layer perpendicular to the surface of the first binding region is greater than that parallel to the surface of the first binding region.
The optical sensor according to claim 1, wherein the first bonding pin and the second bonding pin are parallel and parallel to the first pseudo bonding pin.
The optical sensor according to claim 1, wherein the line width of the first bonding pin is equal to the line width of the second bonding pin and equal to the line width of the first pseudo bonding pin.
The optical sensor according to claim 1, wherein the distance between the adjacent first bonding pin and the first pseudo bonding pin, the adjacent second bonding pin and the first pseudo bonding The spacing between the fixed pins and the spacing between any adjacent first bonding pins are equal.
The optical sensor according to claim 5, characterized in that, for the second bonding pin on the side of the plurality of first bonding pins, the number of second bonding pins is multiple, the second bonding The pins are respectively connected to the second data line;

The spacing between any adjacent first bonding pins is equal to the spacing between any adjacent second bonding pins.
The optical sensor according to claim 1, characterized in that, for the first pseudo bonding pins on one side of the plurality of first bonding pins, the number of the first pseudo bonding pins is multiple.
The optical sensor according to claim 7, wherein the distance between the adjacent first bonding pins and the first pseudo bonding pins is equal to that between any adjacent first pseudo bonding pins spacing.
The optical sensor according to claim 7, wherein the first dummy bonding pins are arranged equidistantly; the distance between any adjacent first dummy bonding pins is 10 microns to 400 microns.
The optical sensor according to claim 7, characterized in that, for the first pseudo bonding pins on the side of the plurality of first bonding pins, the number of first pseudo bonding pins is greater than or equal to 5.
The optical sensor according to claim 1, wherein the number of the first dummy bonding pins is one for the first dummy bonding pins on the side of the plurality of first bonding pins.
The optical sensor according to claim 1, wherein the non-photosensitive pixel units are respectively located on both sides of the columns of photosensitive pixels; the second bonding pins are respectively located in the first bindings Both sides of the pin; there is a first pseudo-binding pin between the second binding pin on one side of the plurality of first binding pins and the plurality of first binding pins, the plurality of first There is a first pseudo binding pin between the second binding pin on the other side of the binding pin and the first binding pins.
The optical sensor according to claim 1, further comprising: a signal readout flexible circuit, the signal readout flexible circuit includes a second binding area, the second binding area and the first binding area In contrast, and the anisotropic conductive layer is located between the first binding area and the second binding area;

The second binding area includes: a plurality of third binding pins, the third binding pins are opposite to the first binding pins, and each third binding pin and each first binding pin pass through each direction The heterosexual conductive layers correspond to one-to-one electrical connection; the fourth bonding pin located on the side of the third bonding pins, the fourth bonding pin is opposite to the second bonding pin, and the fourth bonding pin The foot is electrically connected to the second binding pin through an anisotropic conductive layer; the second pseudo binding pin between the third binding pins and the fourth binding pin, the second The pseudo binding pin is opposite to the first pseudo binding pin.
A method for forming an optical sensor according to any one of claims 1 to 13, characterized in that it includes:

Provide substrate;

A fingerprint sensing circuit layer is formed on the substrate. The fingerprint sensing circuit layer includes a pixel area and a first binding area located on the side of the pixel area; the pixel area of the fingerprint sensing circuit layer includes: a plurality of columns of photosensitive pixel units; one column Or a plurality of columns of non-photosensitive pixel units, the non-photosensitive pixel units are located on the sides of the plurality of columns of photosensitive pixel units; a first data line respectively connected to each column of photosensitive pixel units; a second respectively connected to each column of non-photosensitive pixel units Data line; the first binding area of the fingerprint sensing circuit layer includes: a plurality of first binding pins, the first binding pins are respectively connected to the first data line; and are located in the plurality of first binding pins A second binding pin on the side, the second binding pin is connected to the second data line; a first pseudo binding pin located between the plurality of first binding pins and the second binding pin ;

An anisotropic conductive layer is formed on the first binding area of the fingerprint sensing circuit layer.
The method of forming an optical sensor according to claim 14, further comprising: providing a signal readout flexible circuit, the signal readout flexible circuit including a second binding area, the second binding area including: A plurality of third binding pins, a fourth binding pin located on the side of the third binding pins; a third binding pin between the third binding pins and the fourth binding pin The second pseudo-binding pin; the signal reading flexible circuit is bonded to the anisotropic conductive layer, the anisotropic conductive layer is located between the first binding area and the second binding area, the first The second binding area is opposite to the first binding area, the third binding pin is opposite to the first binding pin, the fourth binding pin is opposite to the second binding pin, and the second pseudo binding lead The feet are opposite to the first pseudo-binding pins, each third binding pin and each first binding pin are electrically connected one-to-one through an anisotropic conductive layer, and the fourth binding pin is electrically conductive through anisotropy The layer is electrically connected to the second binding pin.