CN109099940B

CN109099940B - Sensing device

Info

Publication number: CN109099940B
Application number: CN201810755703.3A
Authority: CN
Inventors: 林其叡; 王澄光; 曹书玮; 游伟盛
Original assignee: AU Optronics Corp
Current assignee: AU Optronics Corp
Priority date: 2018-04-26
Filing date: 2018-07-11
Publication date: 2020-12-04
Anticipated expiration: 2038-07-11
Also published as: CN109099940A; TW201945700A; TWI676787B

Abstract

A sensing device comprises a substrate, a plurality of scanning lines, a plurality of first signal lines, a plurality of second signal lines, a plurality of reference lines, a plurality of element units, a sensing layer and an auxiliary electrode. Each element unit includes a first transistor and a second transistor. The first transistor includes: the first main grid is electrically connected with the scanning line; a first semiconductor layer; the first source electrode is electrically connected with the first signal line; the first drain electrode is electrically connected with the second signal wire; and a first sub-gate. The second transistor includes: the second grid is electrically connected with the first main grid; a second semiconductor layer; the second source electrode is electrically connected with the second signal wire; and a second drain electrically connected to the reference line. The sensing layer is located on the first transistor and the second transistor. The auxiliary electrode is positioned on the sensing layer and is overlapped with the first sub-grid in the normal direction.

Description

Sensing device

Technical Field

The present invention relates to a sensing device, and more particularly, to a sensing device having a double gate transistor.

Background

The thin film sensors using piezoelectric materials are small-sized sensors, and the amount of charge change caused by pressure is very small, so that an amplifier is required to obtain an effective signal. Therefore, the conventional thin film sensor has disadvantages of high cost and low resolution.

Disclosure of Invention

An embodiment of the present invention provides a sensing device having a high resolution and a large-area sensing surface, and having a cost advantage.

The sensing device of an embodiment of the invention includes a substrate, a plurality of scan lines, a plurality of first signal lines, a plurality of second signal lines, a plurality of reference lines, a plurality of element units, a sensing layer, and a plurality of auxiliary electrodes. The substrate has a normal direction. Each element unit includes a first transistor and a second transistor. The first transistor includes: the first main grid is electrically connected with one of the scanning lines; a first semiconductor layer; a first source electrode electrically connected to one of the first signal lines; a first drain electrode electrically connected to one of the second signal lines; and a first sub-gate. The second transistor includes: the second grid is electrically connected with the first main grid; a second semiconductor layer; a second source electrode electrically connected to one of the second signal lines; and a second drain electrically connected to one of the reference lines. The sensing layer is located on the first transistor and the second transistor. The auxiliary electrode is positioned on the sensing layer and is overlapped with the first sub-grid in the normal direction.

In an embodiment of the invention, the first sub-gate and the corresponding auxiliary electrode have substantially the same pattern and area.

In the sensing device according to an embodiment of the invention, since the first transistor is connected in series to the second transistor to form the element unit, and the sensing layer is sandwiched between the first sub-gate and the auxiliary electrode, when a pressure is applied to the sensing layer, a capacitance change is generated at the first sub-gate, so that an output voltage of the element unit when sensing a physical pressure is 1.8 times to 2 times an output voltage when no physical pressure is applied. Therefore, compared with the existing film type pressure sensor, the sensing device of the embodiment can obtain effective signals without matching with an amplifier, can increase the sensing capability, provides a high-resolution pressure diagram and saves the manufacturing cost. In addition, the sensing device of an embodiment of the invention can also form element units through the existing panel manufacturing equipment, and grow the sensing layer in a large range to manufacture the sensing device with high resolution and large sensing area, so as to provide a large-size and high-resolution pressure sensing device, and further reduce the cost.

One of the objectives of the present invention is to increase the sensing capability.

It is an object of the present invention to provide a sensing device of large size.

One of the objectives of the present invention is to save the manufacturing cost.

It is an object of the present invention to provide a high resolution pressure sensing device.

The invention aims to be applied to medical products and used for correcting a standing posture or a walking posture.

The invention aims to be applied to a sleep product to correct the sleep posture.

It is an object of the present invention to provide a high resolution light sensing device.

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

Drawings

Fig. 1 is a partially enlarged top view of a sensing device according to an embodiment of the invention.

FIG. 2 is a partial cross-sectional view of the sensing device of FIG. 1 along the section line A-A'.

FIG. 3 is a partially enlarged top view of a sensing device according to another embodiment of the invention.

FIG. 4 is a partial cross-sectional view of the sensor device of FIG. 3 along the section line A-A'.

FIG. 5 is a top view of a sensing device according to still another embodiment of the invention.

FIG. 6 is an equivalent circuit diagram of the sensing device of FIG. 5.

FIG. 7 is a timing diagram of the sensing device of FIG. 5.

FIG. 8 is a partial cross-sectional view of a sensing device according to another embodiment of the invention.

Description of the symbols

10. 10a, 10b, 10 c: sensing device

100: substrate

120. 120A, 120B: scanning line

130: gate insulating layer

140: dielectric layer

150A, 150B: driving circuit

160. 160 a: sensing layer

170. 170 a: auxiliary electrode

180: protective layer

200. 200A, 200B: element unit

A-A': tangent line

CH 1: first semiconductor layer

CH 2: a second semiconductor layer

CL: reference line

D1: a first drain electrode

D2: second drain electrode

G1A: first main grid

G1B: first sub-grid

G2: second grid

H. H': thickness of

L1: first distance

L2: second distance

S1: a first source electrode

S2: second source electrode

SC: sensing circuit

SL 1: first signal line

SL 2: second signal line

T1: a first transistor

T2: second transistor

TR: region(s)

V_A: input voltage

V_CL: reference voltage

V_G: driving voltage

V_OUT: output voltage

Z: normal direction

Detailed Description

Fig. 1 is a partially enlarged top view of a sensing device according to an embodiment of the invention. FIG. 2 is a cross-sectional view of the sensor device of FIG. 1 along the section line A-A'. It should be noted that the thicknesses or proportions of the various layers or elements of fig. 2 have been shown or described with relative ease and clarity, and have not been drawn to represent the actual thicknesses or proportions of the various layers or elements. Referring to fig. 1 and fig. 2, in the present embodiment, the sensing device 10 includes a substrate 100, a plurality of scan lines 120, a plurality of first signal lines SL1, a plurality of second signal lines SL2, a plurality of reference lines CL, a plurality of unit cells 200, a sensing layer 160, and an auxiliary electrode 170. For clarity, fig. 1 only schematically illustrates one element unit 200 and the corresponding scan line 120, the first signal line SL1, the second signal line SL2, and the reference line CL electrically connected thereto, and omits to illustrate several other elements, but the invention is not limited thereto.

For example, the substrate 100 may be a transparent substrate made of glass, quartz, organic polymer, flexible substrate or other suitable materials, however, the invention is not limited thereto, and in other embodiments, the substrate 100 may also be an opaque/reflective substrate. The opaque/reflective substrate may be made of conductive material, wafer, ceramic or other applicable materials, but the invention is not limited thereto. The substrate 100 has a normal direction Z. The top view of the sensing device 10 shown in fig. 1 is a view viewed from the auxiliary electrode 170 of fig. 2 along the normal direction Z toward the substrate 100.

In the embodiment, the plurality of scan lines 120, the plurality of first signal lines SL1, the plurality of second signal lines SL2, and the plurality of reference lines CL are disposed on the substrate 100. The scan line 120, the first signal line SL1, the second signal line SL2, and the reference line CL may belong to different layers. For example, the scan lines 120 are different from the first signal lines SL1, the second signal lines SL2 and the reference lines CL, and the scan lines 120 are crossed with the first signal lines SL1, the second signal lines SL2 and the reference lines CL, but the invention is not limited thereto.

In the present embodiment, the scan line 120, the first signal line SL1, the second signal line SL2 and the reference line CL are generally made of metal materials for electrical conductivity, but the invention is not limited thereto. In other embodiments, other conductive materials may be used for the scan line 120, the first signal line SL1, the second signal line SL2, and the reference line CL, such as: an alloy, a nitride of a metal material, an oxide of a metal material, an oxynitride of a metal material, or a stacked layer of a metal material and other conductive materials.

In the present embodiment, the cell 200 is disposed on the substrate 100 and includes a first transistor T1 and a second transistor T2. For example, the first transistor T1 includes: a first main gate G1A electrically connected to one of the scan lines 120; a first semiconductor layer CH 1; a first source S1 electrically connected to one of the first signal lines SL 1; a first drain D1 electrically connected to one of the second signal lines SL 2; and a first sub-gate G1B. In the present embodiment, the scan line 120 and the first main gate G1A belong to the same layer. Similarly, the first source S1 and the first signal line SL1 belong to the same layer, but the invention is not limited thereto.

In the present embodiment, the first semiconductor layer CH1 is located above the first main gate G1A. The first source S1 and the first drain D1 are located above the first semiconductor layer CH1, and the first source S1 and the first drain D1 are electrically connected to the first semiconductor layer CH 1. The first sub-gate G1B is located above the first semiconductor layer CH1, and the first sub-gate G1B is floating. For example, the first sub-gate G1B shields the first semiconductor layer CH1 and portions of the first source S1 and the first drain D1 in the normal direction Z. In other words, the first transistor T1 is a dual gate thin film transistor (dual gate tft) as an example.

In the present embodiment, the second transistor T2 includes: a second gate G2 electrically connected to the first main gate G1A, the second semiconductor layer CH2, the second source S2, and one of the second signal lines SL 2; and a second drain D2 electrically connected to one of the reference lines CL. In the present embodiment, the first main gate G1A and the second gate G2 belong to the same layer and are electrically connected to the scan line 120. Similarly, the second source S2 and the second signal line SL2 belong to the same layer, and the second drain D2 and the reference line CL belong to the same layer, but the invention is not limited thereto.

In the present embodiment, the second semiconductor layer CH2 is located above the second gate G2. The second source S2 and the second drain D2 are located above the second semiconductor layer CH2, and the second source S2 and the second drain D2 are electrically connected to the second semiconductor layer CH 2. In other words, the second transistor T2 is a bottom gate Thin Film Transistor (TFT) as an example, but the invention is not limited thereto. According to other embodiments, the second transistor T2 may also be a top gate thin film transistor (top gate tft) or other suitable thin film transistors. In the embodiment, the materials of the first semiconductor layer CH1 and the second semiconductor layer CH2 may be the same, but the invention is not limited thereto. For example, the material of the first semiconductor layer CH1 and the second semiconductor layer CH2 includes an inorganic semiconductor material or an organic semiconductor material, and the inorganic semiconductor material may be one of amorphous silicon (a-si), Indium Gallium Zinc Oxide (IGZO), or polysilicon, but the invention is not limited thereto.

In the embodiment, the second signal line SL2 is located between the first transistor T1 and the second transistor T2 of the cell 200, and the first transistor T1 and the second transistor T2 are respectively electrically connected to the corresponding second signal line SL2, for example, electrically connected to the same second signal line SL 2. In other words, the first transistor T1 and the second transistor T2 are connected in series as the element unit 200.

In addition, the sensing device 10 further includes a gate insulating layer 130 and a dielectric layer 140. In the present embodiment, the gate insulating layer 130 covers the scan line 120 and is located below the first semiconductor layer CH1 and the second semiconductor layer CH 2. The dielectric layer 140 covers the first transistor T1 and the second transistor T2, and is located between the first sub-gate G1B and the first semiconductor layer CH 1. The material of the gate insulating layer 130 and the dielectric layer 140 may be an inorganic material or an organic material or a combination thereof. The inorganic material is, for example, silicon oxide, silicon nitride, silicon oxynitride, or a stacked layer of at least two of the above materials.

In the embodiment, the sensing layer 160 is disposed on the first transistor T1 and the second transistor T2. For example, the sensing layer 160 covers the dielectric layer 140 and the first sub-gate G1B in a whole layer. The material of the sensing layer 160 may be a piezoelectric (piezoelectric) material or a perovskite structure (perovskite structure) material, but the invention is not limited thereto. Under the above configuration, since the sensing layer 160 can be grown on the dielectric layer 140 in a wide range, a large area of sensing surface can be simply fabricated to provide a large-sized sensing device.

In the embodiment, the auxiliary electrode 170 is disposed on the sensing layer 160 and overlaps and completely shields the first sub-gate G1B in the normal direction Z, and the auxiliary electrode 170 is, for example, not overlapping the second gate G2 of the second transistor T2 in the normal direction Z. For example, as shown in fig. 1, when viewed from the auxiliary electrode 170 toward the substrate 100 in the normal direction Z, the auxiliary electrode 170 and the first sub-gate G1B have similar patterns, and the area of the auxiliary electrode 170 is larger than that of the first sub-gate G1B, but the invention is not limited thereto. The auxiliary electrode 170 may serve as one electrode of a sensing capacitor, the first sub-gate G1B of the first transistor T1 may serve as another electrode of the sensing capacitor, and the auxiliary electrode 170, the sensing layer 160 and the first sub-gate G1B of the first transistor T1 may constitute a sensing capacitor.

In addition, in the present embodiment, the sensing device 10 further includes a protection layer 180 disposed on the sensing layer 160. The protection layer 180 covers the sensing layer 160 and the auxiliary electrode 170 in a full layer. The protection layer 180 can prevent the sensing layer 160 or the auxiliary electrode 170 from degrading the resolution of the sensing device 10 due to moisture or other environmental factors.

The following is an example of a preferred embodiment and follows the reference numerals and parts of the previous embodiment, wherein the same reference numerals are used to indicate the same or similar elements and the description is not repeated.

FIG. 3 is a partially enlarged top view of a sensing device according to another embodiment of the invention. FIG. 4 is a partial cross-sectional view of the sensor device of FIG. 3 along the section line A-A'. It should be noted that the thicknesses or proportions of the various layers or elements of fig. 4 have been shown or described with appropriate magnification or reduction for the sake of clarity and ease of illustration, and do not represent actual thicknesses or proportions of the various layers or elements. The sensing device 10a of the present embodiment is similar to the sensing device 10 of fig. 1, and the main differences are: the first sub-gate G1B and the auxiliary electrode 170a have substantially the same pattern and area. That is, the auxiliary electrode 170a and the first sub-gate G1B completely overlap each other. In this way, the first sub-gate G1B and the auxiliary electrode 170a can be fabricated using the same mask (not shown) to simplify the process and save the fabrication cost.

FIG. 5 is a top view of a sensing device according to still another embodiment of the invention. FIG. 6 is an equivalent circuit diagram of the sensing device of FIG. 5.

In this embodiment, the sensing device 10B is similar to the sensing device 10A, and the sensing device 10B further includes driving

circuits

150A and 150B formed on the substrate 100, and the driving

circuits

150A and 150B are electrically connected to the

scan lines

120A and 120B, respectively. In the embodiment, each of the driving

circuits

150A, 150B can be a Gate Driver on Array (GOA) circuit, and respectively provide the driving voltage V at different timings_GTo the

scan lines

120A and 120B of each stage, but the invention is not limited thereto. The driving

circuits

150A and 150B at different levels can simplify the wiring on the substrate 100, increase the margin of the wiring, and increase the area of the sensing function. It is noted here that fig. 5 schematically shows the arrangement in an arrayFour element units are arranged, and two

adjacent element units

200A and 200B in the same column (column) are respectively and electrically connected to the same first signal line SL1, the same second signal line SL2 and the same reference line CL, but the invention is not limited thereto.

In the present embodiment, referring to fig. 5, the adjacent device units 200A in the same row (row) are electrically connected to the same scan line 120A, and the first signal lines SL1 respectively corresponding thereto have a first distance L1 therebetween, and the first distance L1 is, for example, 2000 micrometers (μm) to 20000 μm, but the invention is not limited thereto. In addition, in the embodiment, a second distance L2 is between two

adjacent scan lines

120A and 120B, and the second distance L2 is, for example, 2000 μm to 20000 μm, but the invention is not limited thereto. One skilled in the art can adjust the ranges of the first distance L1 and the second distance L2 for different purposes. In this way, the appropriate spacing between the

element units

200A and 200B can be maintained, so as to avoid the cross talk (crosstalk) phenomenon from causing the reduction of the pressure detection precision, and further prevent the reduction of the detection accuracy.

It is noted that, referring to fig. 2, fig. 4 and fig. 5, the material of the sensing layer 160 of the

sensing devices

10, 10a and 10b according to the embodiments of the present invention includes a piezoelectric material, such as poly (vinylidene fluoride-trifluoroethylene) (P (VDF-TrFe)) or lead zirconate titanate (PZT). The piezoelectric material may be bismuth ferrite (BiFeOX), for example. In addition, the thickness H of the sensing layer 160 is preferably 10 μm to 50 μm, but the invention is not limited thereto. The piezoelectric material has the effect of coupling a stress field and an electric field due to the special arrangement mode among atoms in the crystal lattice, so that the piezoelectric effect is generated. The principle is that when the piezoelectric material is subjected to physical pressure, the electric dipole moment in the material body is shortened due to compression. Therefore, in order to resist the change of the electric dipole moment, the sensing layer 160 generates an equal amount of positive and negative charges on the two opposite surfaces of the sensing layer 160, i.e. the first sub-gate G1B and the

auxiliary electrode

170 or 170a, so as to maintain the original shape. For example, the sensing layer 160 subjected to physical pressure may generate a capacitance change between the first sub-gate G1B and the auxiliary electrode 170 or 170A, thereby affecting the output voltage value of the second signal line SL2 corresponding to the

cell

200, 200A, or 200B.

Referring to fig. 5 and fig. 6, in the present embodiment, each stage of the driving

circuits

150A, 150B is respectively electrically connected to the

scan lines

120A, 120B, and provides the driving voltage V in each stage of scanning at different time intervals_G. Since the time for driving the

scan lines

120A and 120B of each stage is different, the probability of sensing an error signal is reduced and the sensing capability is increased. In the present embodiment, the driving voltage V_GFor example, +70V, but the invention is not limited thereto. Referring to fig. 5 and 6, the second transistors T2 of the

cell units

200A and 200B are electrically connected to a reference line CL having a reference voltage V_CL. In the present embodiment, the reference voltage V_CLFor example, 0V, but the invention is not limited thereto.

As shown in fig. 3, 5 and 6, the second signal line SL2 is located between the first transistor T1 and the second transistor T2. In the present embodiment, the

device units

200A and 200B are both electrically connected to the second signal line SL2 for outputting the voltage V_OUTThe signal of (2) is outputted to the sensing circuit SC, but the invention is not limited thereto. In general, the output voltage V of the element unit 200 via the second signal line SL2_OUTMay be represented by (formula 1):

r1 is the resistance of the first transistor T1 of the cell 200, R2 is the resistance of the second transistor T2 of the cell 200, V_AAn input voltage supplied to the first signal line SL 1.

Referring to fig. 5 and 6, for example, when a pressure is applied to the sensing layer 160 corresponding to the cell 200B, for example, a finger of a user presses or a foot presses, a capacitance change generated by the sensing layer 160 may apply a voltage to the first sub-gate G1B of the first transistor T1 of the cell 200B to change a current value of the first transistor T1, so as to affect the resistors R1 and R2. For example, taking the material of the semiconductor layers CH1 and CH2 as indium gallium zinc oxide as an example, the resistance R2 may be 10 times that of the resistance R1. From the calculation result of (equation 1), after physical pressure is applied to the sensing layer 160, physical pressure is sensedOutput voltage V of pressure_OUTIs composed of

If no physical pressure is applied to the sensing layer 160 and the resistor R2 is the same as the resistor R1, the output voltage V is not applied with physical pressure_OUTIs composed of

That is, when the sensing layer 160 is subjected to a physical pressure, it senses an output voltage V of the physical pressure_OUTOutput voltage V for no applied physical pressure_OUT1.8 times to 2 times, which is strongly related to the electrical characteristics of the transistors T1, T2. Compared with the conventional thin film pressure sensor, the

sensing devices

10, 10a, and 10b of the embodiments of the present invention can obtain effective signals without an amplifier, thereby increasing sensing capability, providing a high resolution pressure pattern, and saving manufacturing cost.

FIG. 7 is a timing diagram of the sensing device of FIG. 5. Referring to fig. 6 and fig. 7, the sensing mechanism of the present embodiment is illustrated by using

adjacent sensing elements

200A and 200B in the same row and a schematic diagram of signal waveforms. For example, if no physical pressure is applied to the upper side of the element unit 200A in fig. 6, the physical pressure is applied to the region TR corresponding to the element unit 200B. At time t1, the driving circuit 150A starts to operate, and the first signal line SL1 is continuously supplied with the input voltage V_A. In the period from the time point t1 to the time point t2, the driving circuit 150A outputs the driving voltage V_GE.g., +70V to the scan line 120A, the second signal line SL2

To the sensing circuit SC. Next, in the period from the time point t2 to the time point t3, the driving circuit 150B outputs the driving voltage V_GTo the scan line 120B, the second signal line SL2 is transmitted

To the sensing circuit SC. Thus, the region TR of the corresponding element unit 200B is sensedThe external force is applied, and so on, the scanning lines after the scanning line 120B receive the driving voltage V in sequence_GThe sensing mechanisms described above are performed sequentially. Further, the output voltage V transmitted through the second signal line SL2_OUTAnd the pressure change and the position distribution image are transmitted to a sensing circuit SC, and then the corresponding pressure change and the position distribution image are displayed by an external display.

In brief, each of the

unit cells

200, 200A, 200B includes: the first transistor T1 is connected in series to the second transistor T2 and electrically connected to the second signal line SL2, and the sensing layer 160 is sandwiched between the first sub-gate G1B and the auxiliary electrode 170. Thus, when the sensing layer 160 is subjected to a physical pressure, the capacitance change generated by the sensing layer 160 may form a voltage at the first sub-gate G1B of the first transistor T1. When the

element units

200, 200A, 200B are subjected to the physical pressure, they sense the output voltage V of the physical pressure_OUTOutput voltage V for no applied physical pressure_OUT1.8 times to 2 times, and this ratio is strongly related to the electrical characteristics of the transistors T1, T2. Therefore, a high resolution pressure pattern can be provided without an amplifier, and the manufacturing cost can be saved.

In addition, the sensing devices 10, 10A, and 10B of the embodiment of the invention can sequentially turn on the element units 200 on the

scan lines

120, 120A, and 120B of each stage in a manner of scanning each stage through the driving

circuits

150A and 150B, so as to reduce the probability of sensing an error signal and increase the sensing capability.

Since the

sensing devices

10, 10a, 10b of the embodiments of the present invention have high resolution and large-area sensing surfaces, they can be applied to medical products to output high-resolution pressure patterns. By means of the pressure diagram, the change of the gravity center of the human body in different postures can be analyzed, and the pressure diagram is used for correcting the standing posture or the walking posture.

Since the

sensing devices

10, 10a, 10b of the embodiments of the present invention have high resolution and large-area sensing surfaces, they can be applied to sleep products to output high-resolution pressure patterns. Through the pressure diagram, the change of the gravity center of the human body in different postures and different time can be analyzed so as to correct the sleeping posture.

It should be noted that, in the following embodiments, the reference numerals and partial contents of the elements in the foregoing embodiments are used, wherein the same reference numerals are used to indicate the same or similar elements, and the description of the portions with the same technical contents omitted may refer to the foregoing embodiments, and the description in the following embodiments is not repeated.

FIG. 8 is a partial cross-sectional view of a sensing device according to another embodiment of the invention. The sensing device 10c shown in the present embodiment is similar to the sensing device 10a shown in fig. 4, and the main difference is that: the material of the sensing layer 160a includes perovskite (perovskite). The perovskite material may be a compound represented by the general formula ABX3, wherein A is an organic or inorganic material; b is an inorganic divalent metal; x is halogen. In the present embodiment, the perovskite may be, for example, CsPbX3, but the present invention is not limited thereto. In addition, the thickness H' of the sensing layer 160a is preferably 10 μm to 50 μm, but the invention is not limited thereto. Because of the unique optoelectronic properties of perovskite materials, a current can be generated in the sensing layer 160a upon illumination. With such a configuration, the sensing device 10c can achieve the same technical effects as those of the above embodiments, and can be applied to provide a high-resolution and large-area light sensing device.

In summary, in the sensing device according to an embodiment of the invention, since the first transistor is serially connected to the second transistor to form an element unit, and the sensing layer is sandwiched between the first sub-gate and the auxiliary electrode, a capacitance change generated by applying a pressure on the sensing layer can form a voltage at the first sub-gate. The voltage can make the output voltage of the element unit when sensing the physical pressure be 1.8 times to 2 times of the output voltage when no physical pressure is applied, so that compared with the existing film type pressure sensor, the sensing device of the embodiment can obtain effective signals without matching an amplifier, can increase the sensing capability, provides a high-resolution pressure diagram and saves the manufacturing cost. In addition, the sensing device of an embodiment of the invention can also form element units through the existing panel manufacturing equipment, and grow the sensing layer in a large range to manufacture the sensing device with high resolution and large sensing area, so as to provide a large-size and high-resolution pressure sensing device, and further reduce the cost. In addition, the sensing device of an embodiment of the invention can sequentially turn on the element units on the scanning lines of each stage in a scanning mode of each stage through the driving circuit to reduce the probability of sensing an error signal, thereby further increasing the sensing capability.

In addition, the sensing device of an embodiment of the invention can be applied to medical products, and the variation of the gravity center of the human body in different postures is analyzed through a high-resolution pressure pattern, so that the sensing device can be used for correcting the standing posture or the walking posture.

In addition, the sensing device of an embodiment of the invention can be applied to sleep products through a high-resolution pressure pattern. The change of the gravity center of the human body in different postures and different time is analyzed to correct the sleeping posture.

In addition, the sensing device of an embodiment of the invention can be applied to provide a high-resolution and large-area light sensing device.

Although the present invention has been described with reference to the above embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention.

Claims

1. A sensing device, comprising:

a substrate having a normal direction;

a plurality of scan lines;

a plurality of first signal lines;

a plurality of second signal lines;

a plurality of reference lines;

a plurality of element units, each element unit comprising:

a first transistor, comprising:

the first main grid is electrically connected with one of the scanning lines;

a first semiconductor layer;

a first source electrode electrically connected to one of the first signal lines;

a first drain electrode electrically connected to one of the second signal lines;

a first sub-gate; and

a dielectric layer between the first sub-gate and the first semiconductor layer; and

a second transistor comprising:

a second grid electrode electrically connected with the first main grid electrode;

a second semiconductor layer;

a second source electrically connected to the first drain and the one of the second signal lines, wherein the one of the second signal lines outputs a signal of an output voltage to a sensing circuit; and

a second drain electrically connected to one of the reference lines;

a sensing layer, suitable for sensing physical pressure, located on the first transistor and the second transistor, the sensing layer covering the dielectric layer and the first sub-gate entirely; and

and a plurality of auxiliary electrodes located on the sensing layer and respectively overlapped with the first sub-gates in the normal direction, wherein each auxiliary electrode, the sensing layer and the corresponding first sub-gate of the first transistor form a sensing capacitor.

2. The sensing device of claim 1, wherein the second signal line is respectively located between the first transistor and the second transistor of each of the element units.

3. The sensing device of claim 1, further comprising: and the at least one driving circuit is formed on the substrate and is electrically connected with the scanning line, wherein the auxiliary electrode is not overlapped with the second grid electrode in the normal direction.

4. The sensing device of claim 1, wherein the material of the sensing layer comprises poly (vinylidene fluoride-trifluoroethylene), lead zirconate titanate, or bismuth iron oxide, and the thickness of the sensing layer is 10 to 50 micrometers.

5. The sensing device as claimed in claim 1, wherein the material of the sensing layer comprises perovskite and the thickness of the sensing layer is 10 to 50 microns.

6. The sensing device of claim 1, wherein the material of each of the first semiconductor layer and the second semiconductor layer comprises an inorganic semiconductor material or an organic semiconductor material, and the inorganic semiconductor material is amorphous silicon, indium gallium zinc oxide or polysilicon.

7. The sensing device of claim 1, wherein one of the first sub-gates and the corresponding auxiliary electrode have substantially the same pattern and area.

8. The sensing device as claimed in claim 1, wherein each of the element units further comprises:

and the gate insulating layer is positioned below the first semiconductor layer and the second semiconductor layer.

9. The sensing device of claim 8, further comprising: a protective layer on the sensing layer.

10. The sensing device as claimed in claim 1, wherein two of the first signal lines electrically connected to two adjacent ones of the element units are spaced apart by a distance of 2000 microns to 20000 microns, and two adjacent scan lines are spaced apart by a distance of 2000 microns to 20000 microns.