WO2017113281A1

WO2017113281A1 - Pressure-sensitive device and manufacturing method

Info

Publication number: WO2017113281A1
Application number: PCT/CN2015/100092
Authority: WO
Inventors: 张波; 张臣雄
Original assignee: 华为技术有限公司
Priority date: 2015-12-31
Filing date: 2015-12-31
Publication date: 2017-07-06
Also published as: CN108604148B; CN108604148A

Abstract

Provided is a pressure-sensitive device (200), comprising: a first substrate (202); a second substrate (208); the second substrate (208) and the plane beneath the first substrate (202) are parallel; a plurality of base walls (204); each base wall (204) of the plurality of base walls (204) comprises an upper end, a lower end, and a side surface; the upper end is in contact with the first substrate (202), and the lower end is in contact with the second substrate (208); the plurality of base walls (204) and the first substrate (202) and second substrate (208) together form a plurality of closed cavities; a plurality of pressure-sensitive elements (206); the pressure-sensitive elements (206) are joined to the flat surface beneath the first substrate (202) in the plurality of cavities, and the impedance of each pressure-sensitive element (206) changes with the change in pressure borne by each pressure-sensitive element (206); a plurality of electrodes (210); every two electrodes (210) of the plurality of electrodes (210) are connected to two points of each pressure-sensitive element (206), respectively, and are used for detecting changes in the impedance of the pressure-sensitive elements (206).

Description

Pressure sensitive device and manufacturing method

Technical field

The present invention relates to the field of pressure sensing, and in particular to a pressure sensing pressure sensitive device and a manufacturing method thereof.

Background technique

Today, touch screens are widely used. FIG. 1 shows a conventional touch screen pressure sensing pressure sensitive device 100. The pressure sensitive device 100 includes a substrate 104, a touchpad 102, and four capacitive pressure sensors 106 at the four corners of the touchpad. When a pressure source such as a finger or the like is applied to the touch panel 102, the displacement of the touch panel 102 is caused, so that the capacitance of the four corner pressure sensors 106 changes, and the magnitude of the pressure can be detected. The pressure values detected by the four pressure sensors 106 will vary depending on where the pressure source is applied. Based on the results of the pressures detected by the four pressure sensors 106, the position of the pressure source can be located by an algorithm of the processor.

In the solution shown in FIG. 1, the touchpad is composed of a non-transparent material, and the four-corner suspended structure is difficult to apply to the surface of the touch screen, and can only be used on the back of the screen to be away from the pressure source, and the precision of the pressure sensing is greatly reduced; The four corner sensors of the structure sense and calculate to locate the pressure source position, and need to perform a data processing calculation after the detection, the response speed is slow, and the precision is low; the structure requires a large floating portion, so that the entire sensor has a large thickness. ,complex structure.

Summary of the invention

In a first aspect, an embodiment of the present invention provides a pressure sensitive device, including:

First substrate;

a second substrate, the second substrate being parallel to a plane below the first substrate;

a plurality of base walls, each of the plurality of base walls including an upper end, a lower end, and a side surface, the upper end being in contact with the first substrate, and the lower end being in contact with the second substrate, the plurality The base wall and the first substrate and the second substrate together form a plurality of closed cavities;

a plurality of pressure sensitive elements respectively attached to the plane below the first substrate in the plurality of cavities, and an impedance of each of the pressure sensitive elements is associated with each The pressure sensitive elements are subject to changes in pressure; and

A plurality of electrodes, each of the two electrodes being connected to two points of each of the pressure sensitive elements, respectively, for detecting a change in impedance of the pressure sensitive element.

Due to the good pressure sensitive property of the pressure sensitive element, the present invention can obtain a large resistance change from a relatively small pressure, thereby having the advantage of measuring the position of the pressure source with high accuracy and high sensitivity. If the first substrate is made of a flexible material, the invention can also be applied to a flexible surface or a curved surface. Furthermore, the present invention has the advantage of being inexpensive to manufacture compared to conventional pressure-sensitive pressure sensitive devices.

In a first possible implementation of the first aspect, the material constituting the pressure sensitive element comprises graphene.

In combination with the first aspect, or the first possible implementation of the first aspect, in a second possible implementation, the plurality of base walls are evenly arranged, and the plurality of closed cavities are equal in volume.

In combination with the first aspect, or any one of the first to the second aspects of the first aspect, in a third possible implementation, the thickness of the cavity is no more than 100 um. The thickness of the cavity is very small, which not only increases the accuracy of the measurement, but also makes the pressure sensitive device easier to integrate into various application systems.

In combination with the first aspect, or any one of the first to third possible implementations of the first aspect, in a fourth possible implementation, the material constituting the first substrate and the base wall comprises a polymer.

In combination with the first aspect, or any one of the first to fourth possible implementations of the first aspect, in the fifth possible implementation, the plurality of pressure sensitive components are the same, and each of the pressure sensitive components The shape includes any of the following shapes: a rectangle, a circle, and an irregular shape.

With reference to the first aspect, or any one of the first to fifth possible implementation manners of the first aspect, in a sixth possible implementation, the plurality of pressure sensitive elements are subjected to pressure from the first substrate The force of the upper plane.

With reference to the first aspect, or any one of the first to sixth possible implementation manners of the first aspect, in the seventh possible implementation, the first substrate, the base wall, and the plurality of pressure sensitive The elements are each constructed of a transparent material and the second substrate is a screen. The first substrate and the pressure sensitive element may each be selected from a transparent material, so that in the touch screen sensing system, the pressure sensitive device may be placed on the first substrate and the pressure sensitive element, and the screen is placed in a lower manner, thereby making the pressure source (such as a hand) ) closer to the pressure sensitive device, making the measurement results more accurate.

In conjunction with the seventh possible implementation of the first aspect, in an eighth possible implementation, the transparent material comprises polyethylene terephthalate.

In conjunction with the first aspect, or any one of the first to sixth possible implementations of the first aspect, in a ninth possible implementation, the first substrate is a sensor substrate, and the second substrate 208 is a cavity Body base.

In a second aspect, an embodiment of the present invention provides a method of manufacturing a pressure sensitive device, including:

Generating a first substrate and a plurality of base walls, each of the plurality of base walls comprising an upper end, a lower end and a plurality of side surfaces, the upper end being in contact with the first substrate;

A plurality of pressure sensitive elements are attached under the first substrate, and an impedance of each of the pressure sensitive elements changes according to a pressure change of each of the pressure sensitive elements;

Contacting the second substrate with the lower end such that the plurality of base walls together with the first substrate and the second substrate form a plurality of closed cavities, wherein among the plurality of pressure sensitive elements Each pressure sensitive element is located in one of the plurality of closed cavities; and

A plurality of electrodes are formed such that each of the plurality of electrodes is connected to two points of each of the pressure sensitive elements, respectively.

In a first possible implementation manner of the second aspect, the attaching the plurality of pressure sensitive elements to the underside of the first substrate comprises:

Covering a material constituting the pressure sensitive element under the first substrate and a lower end and a plurality of side surfaces of each of the base walls;

Using a mask and etch process, the portion of the material below the first substrate is retained and the remainder is removed.

In conjunction with the second aspect, or the first possible implementation of the second aspect, in a second possible implementation, the materials constituting the plurality of pressure sensitive elements include graphene.

With reference to the second aspect, or any one of the first to the second possible implementation manners of the second aspect, in a third possible implementation, the plurality of base walls are evenly arranged, and the plurality of closed The cavities are of equal volume.

With reference to the second aspect, or any one of the first to third possible implementations of the second aspect, in a fourth possible implementation, the thickness in the cavity is not more than 100 um.

In combination with the second aspect, or any one of the first to fourth possible implementations of the second aspect, in a fifth possible implementation, the material constituting the first substrate comprises a polymer.

With reference to the second aspect, or any one of the first to fifth possible implementations of the second aspect, in a sixth possible implementation, the plurality of pressure sensitive elements are the same, and each of the pressure sensitive elements The shape includes any of the following shapes: rectangular, circular, and irregular.

In a third aspect, an embodiment of the present invention provides a method for applying a pressure sensitive device, the method comprising:

The pressure sensitive element receives a force from a plane above the first substrate;

The pressure sensitive element is deformed in response to the applying force;

Detecting, by the electrode, a change in electrical characteristics of the pressure sensitive element due to deformation of the pressure sensitive element;

Based on the change, a pressure condition at the location of the pressure sensitive element is determined to generate a signal to control the system to respond in response to the applied force.

In a first possible implementation of the third aspect, the pressure sensitive device is applied to the mobile terminal system, and by determining that a pressure sensitive component is under pressure, the system activates an application accordingly.

DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description are only It is a certain embodiment of the present invention, and other drawings can be obtained from those skilled in the art without any creative work.

1 is a schematic diagram of a touch screen sensing pressure sensitive device in the prior art.

Fig. 2 is a cross-sectional view showing the pressure sensitive device of the first embodiment of the present invention.

Figure 3 includes a perspective top view of the pressure sensitive device of Figure 1.

4 is a flow chart of a method of manufacturing a pressure sensitive device in accordance with a second embodiment of the present invention.

Figure 5 is a flow chart showing a method of applying a pressure sensitive device in accordance with a third embodiment of the present invention.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

Fig. 2 is a cross-sectional view showing the pressure sensitive device 200 of the first embodiment of the present invention. as shown in picture 2, The pressure sensitive device 200 includes a first substrate 202, a plurality of base walls 204, a plurality of pressure sensitive elements 206, a second substrate 208, and a plurality of electrodes 210. The second substrate 208 is parallel to a plane of the first substrate 202. Each of the plurality of base walls 204 includes an upper end, a lower end, and a plurality of side surfaces. The upper end is in contact with the first substrate 202 and the lower end is in contact with the second substrate 208. A plurality of base walls 204, together with the first substrate 202 and the second substrate 208, form a plurality of closed cavities. In one embodiment, a plurality of base walls 204 are coupled to the first substrate 202. In one embodiment, the plurality of base walls 204 are evenly aligned and the plurality of closed cavities are of equal volume. The material constituting the first substrate 202 and the plurality of base walls 204 includes a polymer such as polyethylene terephthalate or polyvinyl chloride. The thickness in the cavity (i.e., the distance from the upper end of the base wall 204 to the lower end of the base wall 204) is on the order of microns. In one embodiment, the thickness within the cavity is no greater than 100 um. For example, the thickness within the cavity is 50 microns.

A plurality of pressure sensitive elements 206 are respectively attached to the underside of the first substrate 202 in the plurality of cavities, and the impedance of each of the pressure sensitive elements varies with the pressure applied to each of the pressure sensitive elements. A plurality of pressure sensitive elements 206 can cover all or a portion of the area below the first substrate 202 within the cavity. In one embodiment, the material comprising the pressure sensitive element 206 comprises graphene. In one embodiment, the plurality of pressure sensitive elements 206 are identical, and each of the pressure sensitive elements is shaped as any of the following shapes: rectangular, circular, and irregular. Each of the plurality of electrodes 210 is connected to two different points of each pressure sensitive element. In one embodiment, the plurality of pressure sensitive elements 206 are strip-shaped, with each two electrodes being coupled to each end of each pressure sensitive element 206.

The pressure sensitive device 200 can be used as a touch screen sensitive pressure sensitive device. In this application, the second substrate 208 is a screen. When the pressure is pressed downward from the first substrate 202, the pressure-sensitive pressure sensitive member 206 is deformed with the first substrate 202 at which it is attached. The cavity provides space for deformation. The impedance of the pressure sensitive element 206 changes due to its own deformation. The magnitude of the resulting change is related to the size of the self-deformation produced. The size of the deformation itself is related to the magnitude of the pressure applied. An electrical signal is applied to the pressure sensitive element 206 through the electrode 210. For example, a current flows from the electrode 210 from one end of the pressure sensitive element 206, passes through the pressure sensitive element 206, and flows out from the other end of the pressure sensitive element 206. When the impedance of the pressure sensitive element 206 changes, if the voltage applied across the pressure sensitive element 206 does not change, the current flowing through the pressure sensitive element 206 can be detected to change. Since the pressure sensitive element 206 elsewhere is not subjected to pressure, the impedance and the current flowing therethrough do not change. Therefore, when the current flowing through a certain pressure sensitive element 206 changes, it can be judged that the impedance of the pressure sensitive element 206 changes, thereby determining that the pressure sensitive element 206 is under pressure and touch, thereby notifying the system to perform corresponding response. For example, the pressure sensitive device When 200 is applied to a mobile terminal system, by determining that a certain place is under pressure, the system starts an application accordingly.

The pressure sensitive device 200 is not limited to being applied to a touch screen sensing system. For example, the pressure sensitive device 200 can also be applied to the testing of gas pressure in industrial chambers. In this application, the first substrate 202 is a sensor substrate and the second substrate 208 is a cavity substrate. A plurality of airtight adhesives are placed between the base wall 206 and the second substrate 208 to increase airtightness.

Due to the good pressure sensitive property of the pressure sensitive element, the present invention can obtain a large resistance change from a relatively small pressure, thereby having the advantage of measuring the position of the pressure source with high accuracy and high sensitivity. The first substrate and the pressure sensitive element may each be selected from a transparent material, so that in the touch screen sensing system, the pressure sensitive device may be placed on the first substrate and the pressure sensitive element, and the screen is placed in a lower manner, thereby making the pressure source (such as a hand) ) closer to the pressure sensitive device, making the measurement results more accurate. The thickness of the cavity is very small, which not only increases the accuracy of the measurement, but also makes the pressure sensitive device easier to integrate into various application systems. If the first substrate is made of a flexible material, the invention can also be applied to a flexible surface or a curved surface. Furthermore, the present invention has the advantage of being inexpensive to manufacture compared to conventional pressure-sensitive pressure sensitive devices.

3 is a perspective top view of the pressure sensitive device 200 of the first embodiment of the present invention, to facilitate the reader's understanding of the structure of the present invention (the second substrate 208 and the plurality of electrodes 210 are not shown).

4 is a flow chart showing a method 400 of fabricating a pressure sensitive device in accordance with a second embodiment of the present invention. As shown in FIG. 4, method 400 includes, in step 402, generating a first substrate and a plurality of base walls. Each of the plurality of base walls includes an upper end, a lower end, and a plurality of side surfaces. The upper end is in contact with the first substrate. In step 404, a plurality of pressure sensitive elements are attached to the underside of the first substrate. The impedance of each pressure sensitive element varies as the pressure of each of the pressure sensitive elements is subjected to changes. In step 406, the second substrate is brought into contact with the lower end such that the plurality of base walls together with the first substrate and the second substrate form a plurality of closed cavities, wherein each of the plurality of pressure sensitive elements Located in one of several closed cavities. In step 408, a plurality of electrodes are generated such that each of the plurality of electrodes is connected to two points of each pressure sensitive element.

FIG. 5 is a flow chart showing a method 500 of applying a pressure sensitive device in accordance with a third embodiment of the present invention. As shown in FIG. 5, method 500 includes, in step 502, the pressure sensitive element receiving a force from a plane above the first substrate. In step 504, in response to the urging force, the pressure sensitive element is deformed. In step 506, a change in the electrical characteristics of the pressure sensitive element due to deformation of the pressure sensitive element is detected via the electrode. For example, an electrical signal is applied to the pressure sensitive element through the electrode. Such as current from the electrode 210 from the pressure sensitive element One end of the 206 flows in, passes through the pressure sensitive element, and flows out from the other end of the pressure sensitive element. When the impedance of the pressure sensitive element changes due to the shape change of the pressure sensitive element, if the voltage applied across the pressure sensitive element does not change, it is detected that the current flowing through the pressure sensitive element changes. In step 508, based on the change, the pressure condition at the location of the pressure sensitive element is determined to generate a signal to control the system to react in response to the pressure. For example, since the pressure sensitive element elsewhere is not subjected to pressure, the impedance and the current flowing therethrough do not change. Therefore, when the current flowing through a certain pressure sensitive element changes, it can be judged that the impedance of the pressure sensitive element changes, thereby judging that the pressure sensitive element is under pressure and touch, thereby notifying the system to respond accordingly. For example, when the pressure sensitive device 200 is applied to a mobile terminal system, by determining that a certain place is under pressure, the system starts an application accordingly. The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, and thus equivalent changes made in the claims of the present invention are still within the scope of the present invention.

Claims

A pressure sensitive device, comprising:

First substrate;

a second substrate, the second substrate being parallel to a plane below the first substrate;

a plurality of base walls, each of the plurality of base walls including an upper end, a lower end, and a side surface, the upper end being in contact with the first substrate, and the lower end being in contact with the second substrate, the plurality The base wall and the first substrate and the second substrate together form a plurality of closed cavities;

a plurality of pressure sensitive elements respectively attached to the plane below the first substrate in the plurality of cavities, and an impedance of each of the pressure sensitive elements is associated with each The pressure sensitive elements are subject to changes in pressure; and

A plurality of electrodes, each of the two electrodes being connected to two points of each of the pressure sensitive elements, respectively, for detecting a change in impedance of the pressure sensitive element.
The pressure sensitive device according to claim 1, wherein the material constituting the pressure sensitive element comprises graphene.
A pressure sensitive device according to claim 1 or 2, wherein said plurality of base walls are evenly arranged, and said plurality of closed cavities are equal in volume.
The pressure sensitive device according to any one of claims 1 to 3, wherein the cavity has a thickness of not more than 100 μm.
The pressure sensitive device according to any one of claims 1 to 4, wherein the material constituting the first substrate and the base wall comprises a polymer.
The pressure sensitive device according to any one of claims 1 to 5, wherein the plurality of pressure sensitive elements are the same, and the shape of each of the pressure sensitive elements comprises any one of the following shapes: a rectangle , round and irregular shapes.
The pressure sensitive device according to any one of claims 1 to 4, wherein the pressure of the plurality of pressure sensitive elements is derived from a force applied to an upper plane of the first substrate.
The pressure sensitive device according to any one of claims 1 to 7, wherein the first substrate, the base wall and the plurality of pressure sensitive elements are each composed of a transparent material, and the second The substrate is a screen.
The pressure sensitive device of claim 8 wherein said transparent material comprises polyethylene terephthalate.
The pressure sensitive device of any of claims 1-7, wherein the first substrate is a sensor substrate and the second substrate 208 is a cavity substrate.
A method of manufacturing a pressure sensitive device, comprising:

Generating a first substrate and a plurality of base walls, each of the plurality of base walls comprising an upper end, a lower end and a plurality of side surfaces, the upper end being in contact with the first substrate;

A plurality of pressure sensitive elements are attached under the first substrate, and an impedance of each of the pressure sensitive elements changes according to a pressure change of each of the pressure sensitive elements;

Contacting the second substrate with the lower end such that the plurality of base walls together with the first substrate and the second substrate form a plurality of closed cavities, wherein among the plurality of pressure sensitive elements Each pressure sensitive element is located in one of the plurality of closed cavities; and

A plurality of electrodes are formed such that each of the plurality of electrodes is connected to two points of each of the pressure sensitive elements, respectively.
The method according to claim 11, wherein the attaching the plurality of pressure sensitive elements to the underside of the first substrate comprises:

Covering a material constituting the pressure sensitive element under the first substrate and a lower end and a plurality of side surfaces of each of the base walls;

Using a mask and etch process, the portion of the material below the first substrate is retained and the remainder is removed.
A method of applying a pressure sensitive device, the method comprising:

The pressure sensitive element receives a force from a plane above the first substrate;

The pressure sensitive element is deformed in response to the applying force;

Detecting, by the electrode, a change in electrical characteristics of the pressure sensitive element due to deformation of the pressure sensitive element;

Based on the change, a pressure condition at the location of the pressure sensitive element is determined to generate a signal to control the system to respond in response to the applied force.