CN113497160A

CN113497160A - Light sensing device, light sensing panel and light sensing display panel using same

Info

Publication number: CN113497160A
Application number: CN202010271045.8A
Authority: CN
Inventors: 林圣佳
Original assignee: Hexin Photoelectric Co ltd
Current assignee: Hexin Photoelectric Co ltd
Priority date: 2020-04-08
Filing date: 2020-04-08
Publication date: 2021-10-12
Anticipated expiration: 2040-04-08
Also published as: CN113497160B

Abstract

A light sensing device and a light sensing panel and a light sensing display panel using the same are provided. The gate electrode is disposed on the substrate. The semiconductor layer is arranged on the substrate and at least partially overlapped with the grid electrode. The insulating layer separates the gate electrode from the semiconductor layer. The first source/drain electrode and the second source/drain electrode are respectively connected to the semiconductor layer, wherein the semiconductor layer has a first region and a second region between the first source/drain electrode and the second source/drain electrode, wherein the first region overlaps with the gate electrode, and the second region does not overlap with the gate electrode. The reset electrode contacts the semiconductor layer. By resetting the electrodes, residual charges in the semiconductor of the light sensing device can be removed, thereby improving the sensing accuracy.

Description

Light sensing device, light sensing panel and light sensing display panel using same

Technical Field

The invention relates to a light sensing device with a bias grid electrode and an optical panel applied by the same.

Background

The photosensors are capable of converting light into a current or voltage signal. The photoelectric sensor can be manufactured in a thin film transistor form and arranged in an array, and further applied to the fields of optical touch, fingerprint identification, X-ray detection and the like. The photo sensor may include a semiconductor film having an appropriate band gap (band gap) according to the wavelength of light to be absorbed.

However, after converting light into an electrical signal and transmitting the electrical signal through an external circuit, residual charges may exist in the photo sensor, which may affect the photo-sensing signal at the next cycle. Therefore, how to eliminate the residual charge and further improve the sensing accuracy is an important issue at present.

Disclosure of Invention

In various embodiments of the present invention, the reset electrode is designed in the photo sensing device, so that residual charges in the semiconductor can be removed, thereby improving sensing accuracy. In some embodiments, the light sensing device can be used in combination with a sensing switch. Or, by designing the light sensing device with a grid to control part of the channels, the light sensing device can achieve the effects of light sensing and switching at the same time. In some embodiments, the photo sensing device can be applied to a display panel, and the photo sensing device and the pixel electrode in the display panel can be manufactured together through a proper integration process, so that a light shield can be saved.

According to some embodiments of the present invention, a light sensing device includes a substrate, a gate electrode, a semiconductor layer, an insulating layer, a first source/drain electrode, a second source/drain electrode, and a reset electrode. The gate electrode is disposed on the substrate. The semiconductor layer is arranged on the substrate and at least partially overlapped with the grid electrode. The insulating layer separates the gate electrode from the semiconductor layer. The first source/drain electrode and the second source/drain electrode are respectively connected to the semiconductor layer, wherein the semiconductor layer has a first region and a second region between the first source/drain electrode and the second source/drain electrode, wherein the first region overlaps with the gate electrode, and the second region does not overlap with the gate electrode. The reset electrode contacts the semiconductor layer.

In some embodiments, the reset electrode contacts the second region of the semiconductor layer and does not contact the first region of the semiconductor layer.

In some embodiments, the reset electrode contacts the first region and the second region of the semiconductor layer.

In some embodiments, the semiconductor layer is located above the gate electrode.

In some embodiments, the reset electrode contacts the top surface of the semiconductor layer.

In some embodiments, the reset electrode is formed of a transparent conductive material.

According to some embodiments of the present invention, the light sensing panel comprises at least one sensing line, at least one reset line and the light sensing device as described above. The sensing line and the reset line are arranged on the substrate. The grid electrode is electrically connected with the first source electrode/drain electrode, the second source electrode/drain electrode is electrically connected with the sensing line, and the reset electrode is electrically connected with the reset line.

In some embodiments, the photo sensing panel further includes at least one scan line disposed on the substrate, wherein the gate electrode and the first source/drain electrode are electrically connected to the scan line.

In some embodiments, the photo sensing panel further includes at least one bias line, at least one scan line, and a sensing switch device. The bias line and the scan line are disposed on the substrate. The grid electrode and the first source electrode/drain electrode are electrically connected with the bias line. The control end of the sensing switch device is connected with the scanning line, and the second source/drain electrode is electrically connected with the sensing line through the sensing switch device.

In some embodiments, the photo sensing panel further includes at least one data line, a display switch device, and a pixel electrode. The data line is arranged on the substrate. The control end of the display switch device is connected with the scanning line. The pixel electrode is electrically connected with the data line through the display switch device.

In some embodiments, the reset electrode and the pixel electrode are made of the same material.

According to some embodiments of the present invention, a photo-sensing display panel includes a substrate, at least one scan line, at least one data line, at least one sensing line, and at least one pixel unit. The scanning lines, the data lines and the sensing lines are arranged on the substrate. The pixel unit comprises an active element, a pixel electrode and a light sensing device. The active component is electrically connected with the scanning line and the data line. The pixel electrode is electrically connected with the active element. The light sensing device includes a gate electrode, a semiconductor layer, a first source/drain electrode, and a second source/drain electrode. The gate electrode is electrically connected to the scan line, the first source/drain electrode and the second source/drain electrode are respectively connected to the semiconductor layer, the first source/drain electrode is electrically connected to the scan line, the second source/drain electrode is electrically connected to the sensing line, wherein the semiconductor layer has a first region and a second region between the first source/drain electrode and the second source/drain electrode, the first region overlaps with the gate electrode, and the second region does not overlap with the gate electrode.

In some embodiments, the photo sensing device includes a reset electrode contacting the second region of the semiconductor layer, wherein the reset electrode is formed of a transparent conductive material.

Drawings

The aspects of the invention will be better understood from the following detailed description when read in conjunction with the accompanying drawings. It is noted that, in accordance with standard practice in the industry, the various features of the drawings are not drawn to scale. In fact, the dimensions of the features may be arbitrarily scaled for clarity of discussion.

FIG. 1A is a top view of a light-sensing panel according to some embodiments of the present invention;

FIG. 1B is a circuit schematic diagram of a pixel unit of the light-sensing panel of FIG. 1A;

fig. 1C is a schematic top view of a light sensing device in the pixel cell of fig. 1A;

FIG. 1D is a schematic cross-sectional view taken along line 1D-1D of FIG. 1C;

FIG. 1E is a signal diagram of a light-sensing panel operated in accordance with some embodiments of the present invention;

FIG. 2A is a top view of a light sensing device according to some embodiments of the present invention;

FIG. 2B is a schematic cross-sectional view taken along line 2B-2B of FIG. 2A;

FIG. 3 is a top view of a light sensing panel according to some embodiments of the present invention;

FIG. 4 is a top view of a light sensing panel according to some embodiments of the present invention;

FIG. 5A is a top view of a light-sensing panel according to some embodiments of the present invention;

FIG. 5B is a circuit schematic diagram of a pixel unit of the light-sensing panel of FIG. 5A;

fig. 5C is a signal diagram of a light-sensing panel operated in accordance with some embodiments of the present invention;

FIGS. 6-9 illustrate a fabrication process of a photo-sensing panel according to some embodiments of the present invention;

fig. 10 is a cross-sectional schematic view of a light-sensing panel according to some embodiments of the present invention.

[ notation ] to show

100 light sensing panel

110 base plate

112,114,116 area

122,124,126 gate electrode

130 insulating layer

130O opening

142,144,146 semiconductor layer

142A the first region

142B the second region

152A,152B,154A,154B,156A,156B source/drain electrodes

152A' conductive vias

160 insulating layer

172 reset electrode

173 electrically conductive connecting structure

176 pixel electrode

200 switching device

200G, control end

200S first end

200D second end

300 light sensing device

300G, control end

300S first end

300D second end

300R reset terminal

400 display switch device

400G, control end

400S first end

400D second end

GL scanning line

GL 0-GL 3 scanning line

SL sensing line

SL 0-SL 3 sense line

RL reset line

BL bias line

DL data line

PU pixel unit

O1, O2, O3, O4 openings

DC1 drive circuit

DC2 data drive circuit

SW reset switch

SC sensing circuit

G0-G3 scanning signals

TRST reset signal

F1 scanning period

OT operating period

BT blank period

L1, L2 Length

1D-1D: line

2B-2B: wire

10B-10B: thread

Detailed Description

The following description will provide many different embodiments or examples to implement different features of the provided subject matter. Many components and arrangements are described below in order to simplify the present disclosure with regard to specific embodiments. These examples are, of course, intended to be illustrative only and should not be taken as limiting the invention. For example, the statement that a first feature is formed over a second feature includes various embodiments, which encompass both a first feature being in direct contact with the second feature, and additional features being formed between the first and second features, such that direct contact between the two is not made. In addition, the present invention may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and is not intended to in any way limit the scope of the various embodiments and/or configurations discussed.

Furthermore, spatially relative terms, such as "lower," "below," "beneath," "under," "upper," "over," and the like, may be used herein to describe a relationship of an element or feature to another element or feature as illustrated. In use or operation, the spatially relative terms are intended to encompass different orientations of the device in addition to the orientation depicted in the figures. Alternatively, the devices may be rotated (90 degrees or at other angles) and the spatially relative descriptors used herein interpreted accordingly.

Fig. 1A is a top view of a light-sensing panel 100 according to some embodiments of the present invention. The photo-sensing panel 100 includes a plurality of scan lines GL (e.g., scan lines GL 0-GL 3), a plurality of sensing lines SL (e.g., sensing lines SL 0-SL 3), a reset line RL, a bias line BL, and a plurality of pixel units PU. Each pixel unit PU includes a switch device 200 and a photo sensor device 300, wherein the switch device 200 is electrically connected to the scan line GL and the sensing line SL, and the photo sensor device 300 is electrically connected to the bias line BL, the reset line RL and the switch device 200. In various embodiments of the present invention, the scan lines GL extend along a first direction D1, and the sense lines SL extend along a second direction D2, wherein the first direction D1 and the second direction D2 are mutually crossed. For example, the first direction D1 and the second direction D2 are perpendicular to each other. The reset lines RL and the bias lines BL are respectively distributed appropriately to electrically connect the photo sensing devices 300 of the pixel units PU.

Fig. 1B is a circuit schematic diagram of the pixel unit PU of fig. 1A. Referring to fig. 1A and fig. 1B, in the present embodiment, the switch device 200 includes a control terminal 200G, a first terminal 200S and a second terminal 200D, wherein the control terminal 200G is used to control whether the signal terminals are connected to the first terminal 200S and the second terminal 200D. The photo sensing device 300 includes a control terminal 300G, a first terminal 300S, a second terminal 300D, and a reset terminal 300R, wherein a resistance between the first terminal 300S and the second terminal 300D is controllable by the light and the control terminal 300G, so that the photo sensing device 300 can sense the light. In some embodiments, the reset terminal 300R (see fig. 1A) of the photo sensing device 300 is electrically connected to the reset line RL. In fig. 1B, the illustration of the reset terminal 300R is omitted.

In this embodiment, the first terminal 300S and the control terminal 300G of the photo sensing device 300 are connected to a bias potential source BS1 via the bias line BL. The bias potential source BS1 is used to provide a suitable stable bias potential. The second end 300D of the photo sensing device 300 is connected to the first end 200S of the switch device 200, the control end 200G of the switch device 200 is connected to the scan line GL, and the second end 200D of the switch device 200 is connected to the sensing line SL. Thus, when the photo sensing device 300 senses light to change the resistance of the semiconductor layer (e.g., the semiconductor layer 142 of fig. 1C) (e.g., reduce the resistance of the semiconductor layer), the bias potential provided by the bias potential source BS1 is transmitted from the first end 300S to the second end 300D via the bias line BL and further transmitted to the first end 200S of the switch device 200, and transmitted from the first end 200S to the second end 200D via the switch device 200 turned on by the scan line GL, so as to read out the photo sensing signal from the sensing line SL.

In some embodiments of the present invention, the photo sensing panel 100 further includes a driving circuit DC1 and a sensing circuit SC. The driving circuit DC1 is electrically connected to each of the scanning lines GL (e.g., the scanning lines GL0 to GL 3). Therefore, the driving circuit DC1 can provide signals to the scanning lines GL 0-GL 3 in a time sequence. The sensing circuit SC is electrically connected to each sensing line SL (e.g., sensing lines SL0 to SL3) to respectively obtain signals of the sensing lines SL0 to SL 3. In some embodiments, the photo sensing panel 100 further includes a reset switch SW, which can be controlled by a proper reset signal (e.g. the reset signal TRST in fig. 1E) to turn on the reset line RL and a stable potential source BS 2. The potential of the source of stable potential BS2 may be lower than the potential of the source of bias potential BS1, and may be ground, for example. Thereby, the residual charge in the photo sensing device 300 can be eliminated by turning on the reset switch SW. In some embodiments, the reset signal may be provided by an appropriate circuit to control the on/off of the reset switch SW, wherein the circuit may be independent of the driving circuit DC 1. Alternatively, in some other embodiments, the driving circuit DC1 may include the circuit to control whether the reset switch SW is turned on or off by providing a reset signal to the reset switch SW.

In some embodiments of the present invention, referring to fig. 1A, the bias line BL extends along the first direction D1 and is parallel to the scan line GL, and the reset line RL extends along the second direction D2 and is parallel to the sensing line SL. Although not intended to limit the scope of the present invention, in other embodiments, the bias line BL may extend along the second direction D2 and be parallel to the sensing line SL, and the reset line RL may extend along the first direction D1 and be parallel to the scan line GL. In still other embodiments, the bias line BL and the reset line RL may extend along the same direction, such as the first direction D1 or the second direction D2. In various embodiments of the present invention, the scan line GL, the sensing line SL, the reset line RL and the bias line BL are not connected to each other.

Fig. 1C is a schematic top view of the light sensing device 300 in the pixel unit PU of fig. 1A. FIG. 1D is a schematic cross-sectional view taken along line 1D-1D of FIG. 1C. The photo-sensing panel 100 includes a substrate 110. The photo sensing device 300 is disposed on the substrate 110 of the photo sensing panel 100, and the photo sensing device 300 includes the gate electrode 122, the semiconductor layer 142, the source/

drain electrodes

152A and 152B, and the reset electrode 172.

In some embodiments, the gate electrode 122 is disposed on the substrate 110. In some embodiments, the semiconductor layer 142 is disposed on the gate electrode 122 and at least partially overlaps the gate electrode 122. The semiconductor layer 142 and the gate electrode 122 may be separated by an insulating layer 130. The semiconductor layer 142 may be made of a semiconductor material with a suitable energy gap, which absorbs light and changes its own resistance. The source/

drain electrodes

152A and 152B may be connected to both ends of the semiconductor layer 142, respectively.

In the present embodiment, the gate electrode 122 is separated from the source/drain electrode 152B by a gap having a length L2, such that the gate electrode 122 is offset. Thus, the portion of the semiconductor layer 142 of the photo sensing device 300 near the source/drain electrode 152B is controlled by the gate electrode 122. When the photo sensing device 300 is exposed to an environment with a large variation of light, the gate electrode 122 can control and suppress noise of the ambient light, thereby reducing the influence of the ambient light on the sensing result. The light sensing device 300 of the present embodiment can be used for optical fingerprint recognition, and achieves fingerprint recognition by sensing reflected light of finger lines. Since the light sensing device 300 is less affected by ambient light, the accuracy of fingerprint identification can be improved.

More specifically, in some embodiments, the semiconductor layer 142 has a channel region 142CR between the source/

drain electrodes

152A and 152B, the channel region 142CR is divided into a first region 142A and a second region 142B, the first region 142A is located on the gate electrode 122, and the second region 142B is not located on the gate electrode 122. In some embodiments, the boundary between the first region 142A and the second region 142B of the semiconductor layer 142 is aligned with the edge of the gate electrode 122. Thus, the resistance of the entire channel region 142CR of the semiconductor layer 142 (i.e., the first region 142A and the second region 142B) can be adjusted with the light, and the resistance of the first region 142A of the semiconductor layer 142 can be further controlled by the gate electrode 122.

In this embodiment, one side of the semiconductor layer 142 adjacent to the channel region 142CR of the source/drain electrode 152A overlaps the gate electrode 122, and the other side of the semiconductor layer 142 adjacent to the channel region 142CR of the source/drain electrode 152B does not overlap the gate electrode 122. As such, the first region 142A controlled by the gate electrode 122 is located entirely on one side of the dimension of the second region 142B not controlled by the gate electrode 122. This arrangement allows one side of the first region 142A to be directly connected to a conductor (e.g., the source/drain electrode 152A), which is beneficial for precisely controlling the resistance value of the first region 142A of the semiconductor layer 142 using the gate electrode 122. Furthermore, in further embodiments, the gate electrode 122 may also overlap the source/drain electrode 152A.

In some embodiments, the size of the first region 142A controlled by the gate electrode 122 may be different from the size of the second region 142B not controlled by the gate electrode 122. For example, the size of the second region 142B is greater than the size of the portion 142A, e.g., the length L2 of the second region 142B is greater than the length L1 of the first region 142A. Alternatively, in other embodiments, the second region 142B may be smaller than the first region 142A, for example, the length L2 of the second region 142B is smaller than the length L1 of the first region 142A. In some embodiments of the present invention, the length L1 of the first region 142A and the length L2 of the second region 142B can be adjusted, so that the photo sensing device 300 can inhibit the current flowing in the first region 142A through the gate electrode 122 (i.e., the control terminal 300G) when the photo sensing device senses light to generate current, thereby achieving a good switching effect. For example, the length L1 can be designed to be in the range of 2um to 10um, and the length L2 can be designed to be in the range of 2um to 10 um. In embodiments where the light sensing devices 300 achieve good switching effects, the configuration of the switching device 200 may be omitted.

In some embodiments, the reset electrode 172 is disposed on the semiconductor layer 142 and contacts the upper surface of the semiconductor layer 142. In some embodiments, the residual charge of the semiconductor layer 142 may be reduced or removed by the reset electrode 172. In the present embodiment, the reset electrode 172 may be formed of a suitable transparent conductive material, such as Indium Tin Oxide (ITO), nano silver wire, or a combination thereof. For example, the reset electrode 172 may be designed to have a light transmittance greater than 60%, or even greater than 80%. Alternatively, in some embodiments, the reset electrode 172 may be formed of a suitable metal mesh or thin metal wires, so as not to block light. Therefore, light can penetrate through the reset electrode 172, and is absorbed by the semiconductor layer 142 and generated as electrons, so as to maintain the photosensitive effect.

In the present embodiment, the reset electrode 172 is disposed on the second region 142B of the semiconductor layer 142, but not disposed on the first region 142A. Of course, the scope of the invention should not be limited thereby. In other embodiments, the reset electrode 172 may be disposed on the first region 142A and the second region 142B. Alternatively, the reset electrode 172 may be disposed on the first region 142A, but not disposed on the second region 142B. In some other embodiments, the configuration of the reset electrode 172 may be omitted.

In some embodiments, the gate electrode 122 may be formed of a suitable conductive material, such as molybdenum, titanium, chromium, tantalum, tungsten, aluminum, copper, alloys thereof, or combinations thereof. In some embodiments, the semiconductor layer 142 may be formed of a suitable semiconductor material, such as amorphous silicon, other suitable materials, or a combination thereof. The insulating layer 130 may be formed of a suitable insulating material, such as silicon nitride, silicon oxide, silicon oxynitride, or combinations thereof. In some embodiments, the source/

drain electrodes

152A and 152B may be formed of a suitable conductive material, such as molybdenum, titanium, chromium, tantalum, tungsten, aluminum, copper, alloys thereof, or combinations thereof.

It should be understood that, in some embodiments of the present invention, the gate electrode 122, the source/drain electrode 152A, the source/drain electrode 152B, and the reset electrode 172 in fig. 1C and 1D may respectively constitute the control terminal 300G, the first terminal 300S, the second terminal 300D, and the reset terminal 300R of the photo-sensing device 300 in fig. 1A and 1B. In some embodiments, the reset line RL of fig. 1A may be patterned from the same conductive layer as the reset electrode 172, and the reset line RL may comprise the same material as the reset electrode 172, such as the aforementioned transparent conductive material (e.g., ito) or a conductive material used to form a metal grid. Of course, the scope of the invention should not be limited thereto, and in other embodiments, the reset line RL may be patterned with other electrode wires (e.g., the scan line GL, the source/

drain electrodes

152A,152B, or the sensing line SL) by the same conductive layer. The reset line RL may comprise a suitable metal material.

In this embodiment, the scan line GL and the gate electrode 122 in fig. 1A may be formed by patterning the same conductive layer, and the scan line GL and the gate electrode 122 may comprise the same material. In some embodiments, the bias line BL of fig. 1A may be patterned from the same conductive layer as the scan line GL and the gate electrode 122, and the bias line BL, the scan line GL and the gate electrode 122 may comprise the same material. Alternatively, in other embodiments, the bias line BL may be disposed in other manners, for example, the bias line BL may be patterned from the same conductive layer as the source/

drain electrodes

152A and 152B and the sensing line SL, and is not limited to be disposed at the same layer as the scanning line GL. Other details of this embodiment are substantially as described above and will not be further described herein.

In various embodiments of the present invention, the sensing switch device 200 and the photo sensing device 300 may employ N-type channels, the first ends 200S and 300S may be used as sources, and the second ends 200D and 300D may be used as drains. In other embodiments, the sensing switch device 200 and the photo sensing device 300 may adopt a P-type channel, the first ends 200S and 300S may be used as drains, and the second ends 200D and 300D may be used as sources. In still other embodiments, some of these devices may employ N-type channels and some of these devices may employ P-type channels.

Fig. 1E is a signal diagram of a photo-sensing panel 100 operated in accordance with some embodiments of the present invention. Refer to fig. 1A and 1E simultaneously. In some embodiments, the driving circuit DC1 can provide the scan signals G0 to G3 to the scan lines GL0 to GL3, respectively. As shown, in each scan cycle F1, the reset signal TRST further defines an operation period OT and a blank period (blanking) BT in each scan cycle F1. Accordingly, in the operation period OT of each scan cycle F1, the switching devices 200 in each row are turned on sequentially according to the scan signals G0 to G3, so that the sensing circuit SC can read out the photo sensing signals of the photo sensing devices 300 in each row sequentially through the sensing lines SL0 to SL 3.

In this embodiment, the reset signal TRST may be provided to the reset switch SW to control the reset switch SW to be turned on or off. When the reset switch SW is turned on, the blank period BT is entered, and the reset line RL is connected to a stable potential source BS 2. The potential of the source of stable potential BS2 may be lower than the potential of the source of bias potential BS1, and may be ground, for example. Accordingly, by grounding (or connecting to other suitable potentials) the reset electrode 172 (i.e., the reset terminal 300R), some or all of the residual charges in the semiconductor layer 142 of the photo-sensing device 300 can be removed.

In some embodiments, during the blank period BT of each scan cycle F1, the scan lines GL 0-GL 3 may turn on the switch device 200 at a predetermined timing to clear the residual charges in the semiconductor layer 142 of the photo sensing device 300 through the path of the switch device 200. It should be understood that the numbers of the scan signals G0-G3, the scan lines GL 0-GL 3, and the sense lines SL 0-SL 3 are only examples, and should not be construed as limiting the scope of the present invention.

Fig. 2A is a top view of a light sensing device 300 according to some embodiments of the present invention. Fig. 2B is a schematic cross-sectional view taken along line 2B-2B of fig. 2A. This embodiment is similar to the embodiment of fig. 1C and 1D, with the difference that: in this embodiment, the reset electrode 172 at least partially overlaps the gate electrode 122. Specifically, the reset electrode 172 may be disposed on the first region 142A and the second region 142B of the semiconductor layer 142. Other details of this embodiment are substantially as described above and will not be described herein.

Fig. 3 is a top view of a light-sensing panel 100 according to some embodiments of the present invention. This embodiment is similar to the embodiment of fig. 1A, with the difference that: in this embodiment, the pixel unit PU may further include a display switch device 400 and a pixel electrode 176, so that the photo sensing panel 100 can achieve the display effect. The display switch device 400 may include a control terminal 400G, a first terminal 400S and a second terminal 400D, wherein the control terminal 400G is used for controlling whether the first terminal 400S and the second terminal 400D are conducted or not. The control terminal 400G may be connected to the scan line GL. The photo sensing panel 100 further includes a data line DL, and the first end 400S and the second end 400D are respectively connected to the data line DL and the pixel electrode 176. The photo sensing panel 100 further includes a data driving circuit DC2 for providing proper data signals to each data line DL in time sequence. Therefore, through the control of the driving circuit DC1 and the scanning line GL, the data signal provided by the data driving circuit DC2 can be transmitted to each pixel electrode 176 through the data line DL in time sequence, so as to control the light intensity of each pixel, thereby achieving the purpose of display.

In this embodiment, the

display switching devices

400 and 200 of the same pixel unit PU are controlled by the same scanning line GL, so that the

display switching devices

400 and 200 of the same pixel unit PU can be turned on at the same time. Therefore, the pixel unit PU can turn on the data line DL and the pixel electrode 176 via the display switch device 400 at the same time point to achieve the display effect, and turn on the photo sensing device 300 and the sensing line SL via the switch device 200 to achieve the purpose of sensing light. By disposing the photo sensing device 300 and the pixel electrode 176 in the same pixel unit PU, the resolution of the photo sensing device 300 is equivalent to that of the pixel electrode 176 for displaying, so as to improve the sensing resolution. Other details of this embodiment are substantially as described above and will not be further described herein.

Fig. 4 is a top view of a light-sensing panel 100 according to some embodiments of the present invention. This embodiment is similar to the embodiment of fig. 1A, with the difference that: in this embodiment, the pixel unit PU of the photo-sensing panel 100 does not include the switch device 200. In this embodiment, by adjusting the configurations of the gate electrode 122 and the semiconductor layer 142 (see fig. 1C and 1D, for example, adjusting the channel length L2 of the second region 142B), the photo sensing device 300 may sufficiently pass through its own control terminal 300G to prevent the pixel unit PU from being turned on when exposed to light, without the need of matching the switching device 200 (see fig. 1A).

In the present embodiment, the first end 300S and the control end 300G of the photo sensing device 300 are connected to the scan line GL, and the second end 300D of the photo sensing device 300 is connected to the sensing line SL. Thus, when the photo sensing device 300 senses light to change the resistance of the semiconductor layer (e.g., decrease the resistance of the semiconductor layer), the signal of the scanning line GL is transmitted from the first end 300S to the second end 300D, and further transmitted to the sensing line SL. Other details of this embodiment are substantially as described above and will not be described herein.

Fig. 5A is a top view of a light-sensing panel 100 according to some embodiments of the present invention. Fig. 5B is a circuit schematic diagram of the pixel unit PU of the light-sensing panel 100 of fig. 5A. This embodiment is similar to the embodiment of fig. 4, with the difference that: in this embodiment, the pixel unit PU of the photo sensing panel 100 may further include a display switch device 400 and a pixel electrode 176, so that the photo sensing panel 100 can achieve the display effect. The display switch device 400 may include a control terminal 400G, a first terminal 400S and a second terminal 400D, wherein the control terminal 400G is connected to the scan lines GL (e.g., the scan lines GL 0-GL 3). The photo sensing panel 100 further includes a data line DL, and the first end 400S and the second end 400D are respectively connected to the data line DL and the pixel electrode 176.

Fig. 5C is a signal diagram of a photo-sensing panel 100 operated in accordance with some embodiments of the present invention. Reference is also made to fig. 5A to 5C. In this embodiment, the scan signals G0-G3 are respectively provided to the scan lines GL 0-GL 3, and the display switch device 400 and the photo sensor device 300 in the same pixel unit PU can be turned on at the same time through the scan lines GL 0-GL 3. Therefore, at the same time point, the pixel unit PU turns on the data line DL and the pixel electrode 176 via the display switch device 400 to achieve the display effect, and senses light via the light sensing device 300 to achieve the detection purpose. For example, the signals R0 to R3 are sensing signals obtained by the sensing circuit SC through the sensing lines SL0 to SL3, respectively.

In the present embodiment, by disposing the photo sensing device 300 and the pixel electrode 176 in the same pixel unit PU, the resolution of the photo sensing device 300 is equivalent to that of the pixel electrode 176 for displaying, so as to improve the sensing resolution. Other details of this embodiment are substantially as described above and will not be further described herein.

Fig. 6 to 9 illustrate a manufacturing process of the photo-sensing panel 100 according to some embodiments of the present invention. The substrate 110 has regions 112,114 and 116, wherein the photo sensing device, the sensing switch device and the display switch device are respectively formed on the regions 112,114 and 116.

Referring to fig. 6, gate electrodes 122,124, and 126 are formed in regions 112,114, and 116, respectively, on substrate 110. In this regard, a layer of conductive material may be deposited on the substrate 110 and then patterned by suitable means (e.g., etching) to form the gate electrodes 122,124, and 126.

Refer to fig. 7. An insulating layer 130 is formed on the gate electrodes 122,124, and 126. Thereafter, semiconductor layers 142,144, and 146 are formed in the regions 112,114, and 116, respectively, on the insulating layer 130. In this regard, a layer of semiconductor material may be deposited over the insulating layer 130 and then patterned by suitable means (e.g., etching) to form the semiconductor layers 142,144, and 146.

Refer to fig. 8. On the insulating layer 130 and the semiconductor layers 142,144, and 146, a data line DL, a sensing line SL, and source/

drain electrodes

152A,152B,154A,154B,156A, and 156B are formed. In some embodiments, a conductive material layer may be deposited on the structure of fig. 7, and then patterned by an appropriate method (e.g., etching) to form the data line DL, the sensing line SL, and the source/

drain electrodes

152A,152B,154A,154B,156A, 156B.

Thereby, the sensing switch device 200, the light sensing device 300 and the display switch device 400 are formed. In this embodiment, the source/drain electrode 152B of the photo sensing device 300 is connected to the source/drain electrode 154A of the sensing switch device 200.

Next, an insulating layer 160 may be formed on the data line DL, the sensing line SL, and the source/

drain electrodes

152A,152B,154A,154B,156A, 156B. The material of the insulating layer 160 may adopt an appropriate insulating material, such as silicon dioxide, silicon oxynitride, or a combination thereof.

Refer to fig. 9. In the

regions

112 and 116, a reset electrode 172 and a pixel electrode 176 are formed. In this regard, the opening O1-O4 may be opened in the insulating layer 160, a transparent conductive material layer may be deposited thereon, and then the transparent conductive material layer may be patterned by an appropriate method (e.g., etching) to form the reset electrode 172, the pixel electrode 176 and the conductive connection structure 173. Here, the reset electrode 172 may be partially disposed in the opening O1 of the insulating layer 160 to contact the semiconductor layer 142 therebelow. The pixel electrode 176 may be partially disposed in the opening O2 to connect with the underlying source/drain electrode 156B. The conductive connection structure 173 may be partially disposed in the openings O3 and O4 to electrically connect the source/drain electrode 152A to the gate electrode 122. In some embodiments, the openings O3, O4 and the conductive connection structure 173 may be omitted, and the source/drain electrode 152A may be electrically connected to the gate electrode 122 through other embodiments. In some embodiments, the reset electrode 172, the pixel electrode 176 and the conductive connection structure 173 may also be formed by depositing and patterning a metal layer, wherein the reset electrode 172 and the pixel electrode 176 are formed in a metal grid to maintain the light transmittance.

In various embodiments of the present invention, the sensing switch device 200, the photo sensing device 300, and the display switch device 400 may adopt N-type channels, the source/

drain electrodes

152A, 154A, 156A may be used as sources, and the source/

drain electrodes

152B, 154B, 156B may be used as drains. In other embodiments, the sensing switch device 200, the photo sensing device 300, and the display switch device 400 may adopt a P-type channel, the source/

drain electrodes

152A, 154A, 156A may be used as drains, and the source/

drain electrodes

152B, 154B, 156B may be used as sources. In still other embodiments, some of these devices may use N-type channels, and some of these devices may use P-type channels, and thus the types of the source/

drain electrodes

152A,152B,154A,154B,156A,156B are not specifically limited herein.

Fig. 10 is a cross-sectional schematic view of a light-sensing panel 100 according to some embodiments of the present invention. This embodiment is similar to the embodiment of fig. 9, with the difference that: in this embodiment, the conductive via 152A' is used to connect the gate electrode 122 of the source/drain electrode 152A, and the conductive connection structure 173 is omitted. Specifically, in the present embodiment, before depositing the conductive material layer for forming the source/drain electrodes, the opening 130O may be opened in the insulating layer 130, so that when depositing the conductive material layer for forming the source/drain electrodes, the conductive material layer may be deposited in the opening 130O to form the conductive via 152A'. After patterning the conductive material layer, the source/drain electrodes 152A may be connected to the gate electrode 122 via conductive vias 152A' in the opening 130O.

In various embodiments of the present invention, the reset electrode is designed in the photo sensing device, so that residual charges in the semiconductor can be removed, thereby improving sensing accuracy. The light sensing device can be used in combination with a sensing switch. Or, by designing the light sensing device with a grid to control part of the channels, the light sensing device can achieve the effects of light sensing and switching at the same time. In some embodiments, the photo sensing device can be applied to a display panel, and the photo sensing device and the pixel electrode in the display panel can be manufactured together through a proper integration process, so that a light shield can be saved.

The foregoing outlines features of various embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. It will also be understood by those skilled in the art that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A light sensing device, comprising:

a gate electrode disposed on the substrate;

a semiconductor layer disposed on the substrate and at least partially overlapping the gate electrode;

an insulating layer separating the gate electrode from the semiconductor layer;

a first source/drain electrode and a second source/drain electrode respectively connected to the semiconductor layer, wherein the semiconductor layer has a first region and a second region between the first source/drain electrode and the second source/drain electrode, wherein the first region overlaps with the gate electrode, and the second region does not overlap with the gate electrode; and

a reset electrode contacting the semiconductor layer.

2. The light sensing device of claim 1, wherein the reset electrode contacts the second region of the semiconductor layer and does not contact the first region of the semiconductor layer.

3. The light sensing device according to claim 1, wherein the reset electrode contacts the first region and the second region of the semiconductor layer.

4. The light sensing device of claim 1, wherein the semiconductor layer is over the gate electrode.

5. The optical sensing device of claim 1, wherein the reset electrode contacts a top surface of the semiconductor layer.

6. The optical sensing device of claim 1, wherein the reset electrode is formed of a transparent conductive material.

7. A light sensing panel, comprising:

at least one sensing line arranged on the substrate;

at least one reset line disposed on the substrate; and

the light sensing device of claim 1, wherein the gate electrode is electrically connected to the first source/drain electrode, the second source/drain electrode is electrically connected to the sensing line, and the reset electrode is electrically connected to the reset line.

8. The light sensing panel of claim 7, further comprising:

at least one scanning line is arranged on the substrate, wherein the grid electrode and the first source/drain electrode are electrically connected with the scanning line.

9. The light sensing panel of claim 7, further comprising:

at least one bias line disposed on the substrate, wherein the gate electrode and the first source/drain electrode are electrically connected to the bias line;

at least one scanning line arranged on the substrate; and

and a sensing switch device, wherein a control end of the sensing switch device is connected with the scanning line, and the second source/drain electrode is electrically connected with the sensing line through the sensing switch device.

10. The light-sensing panel of claim 8 or 9, further comprising:

at least one data line arranged on the substrate;

a display switch device, wherein a control end of the display switch device is connected with the scanning line; and

and the pixel electrode is electrically connected with the data line through the display switch device.

11. The light-sensing panel according to claim 10, wherein the reset electrode is the same material as the pixel electrode.

12. A light-sensing display panel, comprising:

a substrate;

at least one scanning line arranged on the substrate;

at least one data line arranged on the substrate;

at least one sensing line arranged on the substrate; and

at least one pixel unit arranged on the substrate, wherein the pixel unit comprises;

an active element electrically connected to the scan line and the data line;

a pixel electrode electrically connected to the active device; and

an optical sensing device includes a gate electrode, a semiconductor layer, a first source/drain electrode and a second source/drain electrode, wherein the gate electrode is electrically connected to the scan line, the first source/drain electrode and the second source/drain electrode are respectively connected to the semiconductor layer, the first source/drain electrode is electrically connected to the scan line, the second source/drain electrode is electrically connected to the sense line, wherein the semiconductor layer has a first region and a second region between the first source/drain electrode and the second source/drain electrode, the first region overlaps with the gate electrode, and the second region does not overlap with the gate electrode.

13. The light-sensing display panel of claim 12, further comprising:

a reset electrode contacting the second region of the semiconductor layer, wherein the reset electrode is formed of a transparent conductive material.