TWI793834B - Pressure sensing device and method of fabricating thereof - Google Patents

Abstract

A pressure sensing device includes a first flexible substrate, a pressure sensitive material disposed on the first flexible substrate and a second flexible substrate on the pressure sensitive material. The first flexible substrate includes a first surface facing the pressure sensitive material, a second surface opposite to the first surface, and an opening extending across the first and second surfaces. The pressure sensing device includes a group of electrodes extending from an inside of the opening to the first surface and the second surface. The group of electrodes is electrically connected to the pressure sensitive material and includes a first electrode and a second electrode. The first electrode and the second electrode individually cover part of an inner surface of the opening, part of the first surface and part of the second surface. The first electrode and the second electrode face to and are spaced apart from each other.

Description

Pressure sensing device and manufacturing method thereof

The disclosure relates to a pressure sensing device and a manufacturing method thereof.

The pressure sensing device can sense the pressure exerted by the user on it, and convert the deformation generated by the pressure into an electrical signal or other required forms of information output. The signal output by the force sensing device can trigger the feedback module, thereby providing users with an intuitive experience. For example, the touch panel can provide different vibration feedbacks according to different pressure levels of the user. If the pressure sensing device cannot provide accurate signals, the feedback module may not be able to provide accurate feedback, which will cause user perception errors or inconvenient operation.

Therefore, various industry players strive to improve the precision of the pressure sensing device and its manufacturing process to ensure accurate output signals and improve the sensing accuracy of the pressure sensing device.

According to some embodiments of the disclosure, a pressure sensing device includes a first flexible substrate, a pressure-sensitive material disposed on the first flexible substrate, and a second flexible substrate disposed on the pressure-sensitive material. The second flexible substrate has a first surface facing the pressure-sensitive material, a second surface opposite to the first surface, and an opening extending to the first surface and the second surface. The pressure sensing device further includes an electrode set disposed in the opening and extending from the opening to the first surface and the second surface, wherein the electrode set is electrically connected to the pressure-sensitive material and has a first electrode and a second electrode. The first electrode covers part of the inner surface, part of the first surface and part of the second surface of the opening. The second electrode covers part of the inner surface, part of the first surface and part of the second surface of the opening, wherein the second electrode and the first electrode are arranged opposite to each other and separated from each other.

In some embodiments, in a plan view of the pressure sensing device viewed from the second surface, the first electrode and the second electrode exhibit mirror symmetry.

In some embodiments, the first electrode has a first concave surface, and the second electrode has a second concave surface, and the first concave surface and the second concave surface face each other.

In some embodiments, the pressure-sensitive material includes elastic resin and several conductive materials, wherein the conductive material is distributed in the elastic resin.

In some embodiments, the conductive material includes silver.

In some embodiments, the conductive material also includes tin or bismuth.

In some embodiments, the material of the electrode set includes tin or silver.

In some embodiments, the electrode set disposed on the first surface of the second flexible substrate directly contacts the pressure-sensitive material.

In some embodiments, the pressure sensing device further includes a protective layer filling the opening of the second flexible substrate and distributed between the first electrode and the second electrode.

In some embodiments, the electrode set disposed on the inner surface of the opening directly contacts the protective layer.

According to some embodiments of the present disclosure, a method of manufacturing a pressure sensing device includes providing a first flexible substrate, disposing a pressure sensitive material on the first flexible substrate, providing a first surface having a first surface opposite to the first surface. The second flexible base material on the two surfaces, and openings are formed in the second flexible base material. The opening extends to the first surface and the second surface. The method of manufacturing the pressure sensing device further includes forming a conductive layer on the inner surface of the opening and on the first surface, wherein the conductive layer has a continuous edge in a plan view viewed from the second surface. The method of manufacturing the pressure sensing device further includes removing the first portion of the conductive layer and the second portion opposite the first portion such that a continuous edge of the conductive layer is broken to separate the first electrode and the second electrode. The method for manufacturing the pressure sensing device further includes pressing the first flexible substrate and the second flexible substrate so that the pressure-sensitive material is electrically connected to the first electrode and the second electrode, wherein the pressure-sensitive material is interposed between the first flexible substrate and the second flexible substrate. Between two soft substrates.

In some embodiments, after removing the first portion and the second portion, the first electrode and the second electrode exhibit mirror symmetry in a plan view viewed from the second surface.

In some embodiments, forming the conductive layer includes using an electroplating process.

In some embodiments, the method of manufacturing the pressure sensing device further includes forming a silver layer or a tin layer on the first electrode and the second electrode before laminating the first flexible substrate and the second flexible substrate.

In some embodiments, the lamination temperature for laminating the first flexible substrate and the second flexible substrate is between 180 degrees Celsius and 260 degrees Celsius.

In some embodiments, the first flexible substrate and the second flexible substrate are pressed together so that both the first electrode and the second electrode directly contact the pressure-sensitive material.

In some embodiments, the method of manufacturing a pressure sensing device further includes forming a protective layer on the second flexible substrate, wherein the protective layer is distributed between the first electrode and the second electrode.

Embodiments of the disclosure provide pressure devices and methods of making the same. The sensing accuracy of the pressure sensing device is improved by laminating the first flexible base material with the pressure-sensitive material and the second flexible base material with the electrode group and forming the electrode group through the same hole.

When an element such as a layer, film, region, or substrate is referred to as being "on" or "connected to" another element, it can be directly on or connected to the other element or intervening elements. can also exist. In contrast, when an element is referred to as being "directly on" or "directly connected to" another element, there are no intervening elements present. As used herein, "connected" may refer to physical and/or electrical connection. Furthermore, "electrically connected" or "coupled" may mean that other elements exist between two elements.

Additionally, relative terms such as "lower" or "bottom" and "upper" or "top" may be used herein to describe one element's relationship to another element as shown in the figures. It will be understood that relative terms are intended to encompass different orientations of the device in addition to the orientation depicted in the figures. For example, if the device in one of the figures is turned over, elements described as being on the "lower" side of other elements would then be oriented on "upper" sides of the other elements. Thus, the exemplary term "below" can encompass both an orientation of "below" and "upper," depending on the particular orientation of the drawing. Similarly, if the device in one of the figures is turned over, elements described as "below" or "beneath" other elements would then be oriented "above" the other elements. Thus, the exemplary terms "below" or "under" can encompass both an orientation of above and below.

As used herein, "about," "approximately," or "substantially" includes stated values and averages within acceptable deviations from a particular value as determined by one of ordinary skill in the art, taking into account the measurements in question and the relative A specific amount of measurement-related error (ie, a limitation of the measurement system). For example, "about" can mean within one or more standard deviations of the stated value.

Unless defined otherwise, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted to have a meaning consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted as idealized or An overly formal sense, unless explicitly so defined herein.

The pressure sensing device can sense the pressure exerted on it, and convert the deformation generated by the pressure into an electrical signal or other required forms of information output. Therefore, the relationship (for example, linear relationship) between the magnitude of the pressure applied by the outside can be obtained through the change of the electrical signal of the pressure sensing device. If the electrical signal is interfered, the judgment of the pressure will be affected, resulting in a decrease in the sensing accuracy of the pressure transmission device. Therefore, the embodiments of the present disclosure provide a pressure sensing device and its manufacturing method to improve the precision of the pressure sensing device and its manufacturing process so as to ensure accurate output signals and improve the sensing accuracy of the pressure sensing device.

It should be noted that, unless otherwise specified, when the following embodiments are shown or described as a series of operations or events, the description order of these operations or events should not be limited. For example, some operations or events may be undertaken in a different order than in the present disclosure, some operations or events may occur concurrently, some operations or events may not be required, and/or some operations or events may be repeated. Moreover, the actual manufacturing process may require additional operations before, during, or after each step to completely form the display device. Therefore, this disclosure may briefly illustrate some of these additional operations.

Please refer to FIG. 1A and FIG. 1B at the same time. FIG. 1A is a top view of a pressure sensing device in one of the manufacturing stages according to some embodiments of the disclosure, and FIG. 1B is a pressure sensing device according to some embodiments of the disclosure. Cross-sectional view of the sensing device along the line A-A in Fig. 1A. First, in step S100 , a first flexible substrate 100 and a pressure-sensitive material 102 are provided, wherein the pressure-sensitive material 102 is disposed on the first flexible substrate 100 .

The material of the first flexible substrate 100 may include a flexible polymer material, such as polyimide (polyimide, PI), thermoplastic polyimide (thermoplastic polyimide, TPI), polyethylene terephthalate (polyethylene terephthalate, PET), polyethylene naphthalate (polythylene naphthalate, PEN), polyurethane (polyurethane, PU), thermoplastic polyurethane (thermoplastic polyurethane, TPU), other suitable materials, derivatives of the above, or the above materials any combination of . For example, the material of the first flexible substrate 100 may include thermoplastic polyimide (TPI).

The pressure-sensitive material 102 may include elastic resin (not shown) and several conductive materials (not shown), wherein the elastic resin serves as an insulating matrix, and the conductive material is distributed in the elastic resin to provide electrical conduction. The elastic resin of the pressure sensitive material 102 may include polydimethylsiloxane (polydimethylsiloxane, PDMS), thermoplastic polyurethane (thermoplastic polyurethane, TPU), polyester (polyester) resin, epoxy (epoxy) resin, silicone (silicon) resin , or other suitable materials, or any combination of the above materials. For example, the elastic resin of the pressure-sensitive material 102 may include PDMS. In some embodiments, the elastic resin in the material forming the pressure-sensitive material 102 is between 15 wt % (weight percent) and 20 wt %. In some embodiments, the elongation of the elastic resin ranges from 5% to 50%.

The conductive material of the pressure-sensitive material 102 may include metals, such as silver conductive powder, conductive nano-silver wire, multi-branched silver, carbon conductive powder, conductive carbon nanotubes, nickel conductive powder, silver-coated aluminum conductive powder , silver-coated copper conductive powder, silver-coated nickel conductive powder, silver-coated glass conductive powder, other suitable metals, or any combination of the above materials. The conductive material of the pressure sensitive material 102 may also include oxides, such as zinc oxide powder, indium tin oxide powder, ruthenium dioxide powder, other suitable materials, or any combination of the above materials. For example, the conductive material of the pressure-sensitive material 102 may include silver, such as silver conductive powder, conductive silver nano wire, dendritic silver, silver-coated copper conductive powder, and the like. The conductive material may further include tin or bismuth. For example, in the case that the conductive material of the pressure-sensitive material 102 has silver, the conductive material of the pressure-sensitive material 102 may further include tin. In some embodiments, the conductive material in the material forming the pressure-sensitive material 102 is between 20 wt % (weight percent) and 25 wt %.

In some other embodiments, the material forming the pressure-sensitive material 102 may further include a solvent, such as methyl ethyl ketone, isophorone, other suitable solvents, or any combination of the above-mentioned materials. This is the limit. In some embodiments, the solvent in the material forming the pressure-sensitive material 102 is between 55 wt % (weight percent) and 65 wt %.

Please refer to FIG. 2A and FIG. 2B at the same time. FIG. 2A is a top view of a pressure sensing device in one of the manufacturing stages according to some embodiments of the disclosure, and FIG. 2B is a pressure sensing device according to some embodiments of the disclosure. A cross-sectional view of the sensing device along line A-A in Fig. 2A. Next, in step S200 , a second flexible substrate 200 is provided, which includes a first surface S1 and a second surface S2 opposite to the first surface S1 .

The material of the second flexible substrate 200 may include flexible polymer materials, such as PI, TPI, PET, PEN, PU, TPU, other suitable materials, derivatives of the above, or any combination of the above materials. For example, the material of the second flexible substrate 200 may include TPI. In some embodiments, the material of the second flexible substrate 200 may be substantially the same as that of the first flexible substrate 100 .

In the embodiment shown in FIG. 2A and FIG. 2B , the circuit layer 202 is formed on the first surface S1 and the second surface S2 of the second flexible substrate 200 . In some embodiments, the wiring layer 202 may only be formed on the first surface S1 or the second surface S2. The material of the circuit layer 202 may include metal, such as aluminum, gold, silver, copper, tin or other metals, or any combination of the above materials. In some embodiments, the wiring layer 202 may be a copper wiring. It should be noted that, in order to simplify the drawing for clarity, the circuit layer 202 only draws a part of the circuit, such as the part connected to the electrode set 500 (see FIG. 5A ). In practical applications, the complete circuit layer 202 can be formed according to product design or process conditions. The wiring layer 202 can be made by an additive method, a semi-additive method or a subtractive method.

Please refer to FIG. 3A and FIG. 3B at the same time. FIG. 3A is a top view of a pressure sensing device in one of the manufacturing stages according to some embodiments of the disclosure, and FIG. 3B is a pressure sensing device according to some embodiments of the disclosure. A cross-sectional view of the sensing device along line A-A in Fig. 3A. Next, in step S300 , a first opening O1 is formed in the second flexible substrate 200 , wherein the first opening O1 extends to the first surface S1 and the second surface S2 . In other words, the first opening O1 may be a through hole passing through the second flexible substrate 200 so that the second flexible substrate 200 has a hollow structure communicating with the first surface S1 and the second surface S2.

The shape of the first opening O1 in a plan view (for example, in a plan view viewed from the second surface S2) may be circular, elliptical, rectangular, rhombus, polygonal, or any shape with a symmetrical structure, but the present disclosure does not limited to this. For example, the first opening O1 can be a line-symmetric figure with at least one axis of symmetry. If the shape of the first opening O1 is folded along the axis of symmetry, the parts on both sides of the axis of symmetry can overlap with each other. In the embodiment shown in FIG. 3A , the first opening O1 may be circular.

The forming method of the first opening O1 may include laser drilling, mechanical drilling, other suitable techniques, or any combination of the above materials. In some embodiments, the location of the first opening O1 can be within the range of the wiring layer 202, as shown in FIG. 3A. In some embodiments, the size of the first opening O1 is between 0.4 millimeters (mm) and 1 mm. For example, in an embodiment where the first opening O1 is circular, the diameter of the first opening O1 may be in a range of 0.4 mm to 1 mm.

Please refer to FIG. 4A and FIG. 4B at the same time. FIG. 4A is a top view of a pressure sensing device in one of the manufacturing stages according to some embodiments of the disclosure, and FIG. 4B is a pressure sensing device according to some embodiments of the disclosure. A cross-sectional view of the sensing device along line A-A in Fig. 4A. Next, in step S400 , a conductive layer 400 is formed on the first opening O1 and the second flexible substrate 200 . In detail, the conductive layer 400 is formed on the inner surface of the first opening O1, and on the first surface S1 and the second surface S2 adjacent to the first opening O1.

In some embodiments, the conductive layer 400 may be a continuous film layer extending from the inner surface of the first opening O1 to the first surface S1 and the second surface S2 . In some further embodiments, the conductive layer 400 completely covers the inner surface of the first opening O1, and is formed on the first surface S1 and the second surface S2 along the shape of the first opening O1. Therefore, in the top view in FIG. 4A (for example, in the top view viewed from the second surface S2), the conductive layer 400 has a continuous edge, and the shape of this continuous edge is basically consistent with the shape of the first opening O1. .

In some embodiments, the method of forming the conductive layer 400 may include setting a patterned mask to expose the area where the conductive layer 400 is to be formed, depositing a conductive material, and removing the patterned mask. In some other embodiments, the forming method of the conductive layer 400 may include blanket depositing the conductive material, and removing part of the conductive material to leave a region where the conductive layer 400 is to be formed. Deposition methods may include evaporation, sputtering, electroplating, other suitable deposition techniques, or any combination of the above materials. For example, forming the conductive layer 400 may include using an electroplating process. In the embodiment using the electroplating process, the conductive layer 400 can have a relatively smooth surface by adjusting the electroplating parameters (such as current density), so as to reduce noise during the transmission of electrical signals, which can help to improve the reliability of the device. Spend.

The material of the conductive layer 400 may include metal, such as aluminum, gold, silver, copper, tin or other metals, or any combination of the above materials. In some embodiments, the material of the conductive layer 400 may include copper.

The second flexible substrate 200 may include a trimmed region R, which is shown in broken lines in FIG. 4A. The cutting area R may cover part of the circuit layer 202 and part of the conductive layer 400 . Therefore, the conductive layer 400 can further distinguish different parts. For example, as shown in FIG. 4A, the conductive layer 400 may include a first portion 400-1, a second portion 400-2, a third portion 400-3 and a fourth portion 400-4, wherein the first portion 400-1 and The second portion 400-2 is within the range of the trimming area R, while the third portion 400-3 and the fourth portion 400-4 are outside the range of the trimming area R. Referring to FIG.

Please refer to FIG. 5A and FIG. 5B at the same time. FIG. 5A is a top view of a pressure sensing device in one of the manufacturing stages according to some embodiments of the disclosure, and FIG. 5B is a pressure sensing device according to some embodiments of the disclosure. A cross-sectional view of the sensing device along line A-A in Fig. 5A. Next, in step S500 , the cutting region R is removed, that is, part of the second flexible substrate 200 , part of the circuit layer 202 and part of the conductive layer 400 are removed. After the removal, a second opening O2 is formed in the second flexible substrate 200 . The second opening O2 can be regarded as a collection area of the first opening O1 and the trimming area R in FIG. 4A . In some embodiments, the method for removing the cut region R may include aligning the cut region R with a punch jig, and then performing punching to remove the cut region R.

During the removal process, the first portion 400-1 of the conductive layer 400 and the second portion 400-2 relative to the first portion 400-1 are removed, while the remaining third portion 400-3 and fourth portion 400- 4 become the first electrode 500-1 and the second electrode 500-2 respectively. The first electrode 500-1 and the second electrode 500-2 are disposed opposite to and separated from each other.

In detail, the continuous edge of the conductive layer 400 (see FIG. 4A ) is broken during the removal process to separate the first electrode 500-1 and the second electrode 500-2, wherein the first electrode 500-1 is approximately The same as the third part 400-3 and the second electrode 500-2 are substantially the same as the fourth part 400-4. Since the first electrode 500-1 and the second electrode 500-2 are separated from the conductive layer 400 (see FIG. -1 and the second electrode 500-2 are formed substantially simultaneously. The first electrode 500 - 1 and the second electrode 500 - 2 may be collectively referred to as an electrode group 500 .

A distance between the first electrode 500-1 and the second electrode 500-2 in the electrode group 500 may be defined by the first opening O1. A plurality of electrode groups 500 may be formed by forming a plurality of first openings O1. The first opening O1 can determine the arrangement of the electrode group 500, and by controlling the dimensional accuracy of the first opening O1 to control the distance between the first electrode 500-1 and the second electrode 500-2, it helps to improve the distance between the electrode group 500. consistency between.

Furthermore, the conductive layer 400 (see FIG. 4A ) can be considered as a previous stage of the electrode set 500, so that the electrode set 500 can have the same characteristics as the conductive layer 400 (see FIG. The layer 400 (see FIG. 4A ) is the same material, and the electrode set 500 may have a structure similar to that of the conductive layer 400 (see FIG. 4A ), which will not be described in detail here. For example, the electrode group 500 is disposed in the second opening O2, and extends from the second opening O2 to the first surface S1 and the second surface S2. In detail, the first electrode 500-1 in the electrode set 500 covers part of the inner surface of the second opening O2, part of the first surface S1 and part of the second surface S2, and the second electrode 500-2 in the electrode set 500 covers A part of the inner surface of the second opening O2, a part of the first surface S1 and a part of the second surface S2, wherein the areas covered by the first electrode 500-1 and the second electrode 500-2 do not overlap with each other.

In some embodiments, after removing the first portion 400-1 and the second portion 400-2 of the conductive layer 400, the formed first electrode 500-1 and the second electrode 500-2 exhibit line symmetry (or called mirror symmetry), but the disclosure is not limited thereto. For example, as shown in FIG. 5A, the reference axis of symmetry 510 is between the first electrode 500-1 and the second electrode 500-2. The first electrode 500-1 and the second electrode 500-2 on both sides may overlap each other. In the embodiment shown in FIG. 5A, the first electrode 500-1 has a first concave surface, the second electrode 500-2 has a second concave surface, and the first concave surface and the second concave surface face each other.

Alternatively, the distance between the first electrode 500 - 1 and the reference axis of symmetry 510 is substantially equal to the distance between the second electrode 500 - 2 and the reference axis of symmetry 510 . For example, the first electrode 500-1 is separated from the reference axis of symmetry 510 by a first distance D-1, and at the corresponding position, the second electrode 500-2 is separated from the reference axis of symmetry 510 by a second distance D-2, wherein The first distance D-1 is substantially equal to the second distance D-2.

Please refer to FIG. 6A and FIG. 6B at the same time. FIG. 6A is a top view of a pressure sensing device in one of the manufacturing stages according to some embodiments of the disclosure, and FIG. 6B is a pressure sensing device according to some embodiments of the disclosure. A cross-sectional view of the sensing device along line A-A in Fig. 6A. Next, in step S600, the first flexible substrate 100 and the second flexible substrate 200 are pressed together, so that the pressure-sensitive material 102 is electrically connected to the first electrode 500-1 and the second electrode 500-2, wherein the pressure-sensitive material 102 Interposed between the first flexible substrate 100 and the second flexible substrate 200 .

In detail, after the first flexible substrate 100 and the second flexible substrate 200 are pressed together, the third flexible substrate 600 is formed together. Therefore, the third flexible substrate 600 can have the first flexible substrate 100 and the second flexible substrate 200 . In some embodiments, an adhesive material 602 can be disposed between the first flexible substrate 100 and the second flexible substrate 200 to adhere the first flexible substrate 100 and the second flexible substrate 200 . Therefore, the third flexible substrate 600 may have an adhesive material 602, but the present disclosure is not limited thereto.

In the embodiment shown in FIG. 6B, the second flexible substrate 200 faces the pressure-sensitive material 102 with the first surface S1, so that the electrode group 500 located on the first surface S1 directly contacts the pressure-sensitive material 102, so that the electrodes The group 500 is electrically connected to the pressure sensitive material 102 . In some embodiments, both the first electrode 500-1 and the second electrode 500-2 are in direct contact with the pressure-sensitive material 102, so that the separated first electrode 500-1 and the second electrode 500-2 can pass through the pressure-sensitive material. 102 and electrically connected.

The pressing temperature for laminating the first flexible substrate 100 and the second flexible substrate 200 is within a range of about 180 degrees Celsius and about 260 degrees Celsius. For example, in some further embodiments, a press temperature of about 180 degrees Celsius may be used depending on the selected material properties. During the pressing process, the material of the electrode set 500 may fuse due to contact with the conductive material of the pressure-sensitive material 102 . In order to reduce the contact resistance between the electrode set 500 and the pressure-sensing material 102 , in some embodiments, the conductive material of the pressure-sensing material 102 may have silver to achieve better electrical performance after fusion. In some embodiments, the silver conductive material may have a tip structure (such as conductive silver nanowires, multi-branched silver, etc.), wherein the tip structure of silver may be preferentially fused with the material of the electrode set 500 to reduce contact resistance. The conductive material of the pressure-sensitive material 102 may further contain tin or bismuth, so as to form a better fusion with the material of the electrode set 500 and reduce the contact resistance.

In addition to selecting the conductive material of the pressure-sensitive material 102 to reduce the contact resistance, the electrode group 500 may also select the material to reduce the contact resistance. In some embodiments, before laminating the first flexible substrate 100 and the second flexible substrate 200 , the electrode assembly 500 may be surface treated so that the material of the electrode assembly 500 has tin or silver. For example, before laminating the first flexible substrate 100 and the second flexible substrate 200, a silver layer or a tin layer (not shown) is formed on the first electrode 500-1 and the second electrode 500-2. In some embodiments, the surface treatment method may include performing an electroless plating (electroless plating) process on the electrode set 500 . When the material of the electrode set 500 is tin or silver, after pressing, the contact resistance between the electrode set 500 and the pressure-sensitive material 102 can be lower.

Please refer to FIG. 7A and FIG. 7B at the same time. FIG. 7A is a top view of a pressure sensing device in one of the manufacturing stages according to some embodiments of the disclosure, and FIG. 7B is a pressure sensing device according to some embodiments of the disclosure. A cross-sectional view of the sensing device along line A-A in Fig. 7A. Next, in step S700 , a protective layer 700 is formed on the second flexible substrate 200 , and then the pressure sensing device 702 is manufactured.

In some embodiments, the protective layer 700 is disposed in the second opening O2 (see FIG. 6A ) of the second flexible substrate 200 and distributed between the first electrode 500-1 and the second electrode 500-2. In some further embodiments, the protective layer 700 fills the second opening O2 (see FIG. 6A ) of the second flexible substrate 200, so that the inner surfaces of the second opening O2 directly contact the protective layer 700, that is, to protect The layer 700 directly contacts the first electrode 500-1 and the second electrode 500-2. The material of the protective layer 700 may include any suitable insulating material for insulation and protection. In some embodiments, the material of the protective layer 700 may be a solder mask.

When pressure is applied to the pressure sensing device 702 to generate deformation, it means that the third flexible substrate 600 (especially the second flexible substrate 200 ) is stretched, and thus the pressure-sensitive material 102 is also stretched and deformed. After the pressure-sensitive material 102 is stretched, the distance between the conductive materials (not shown) in the pressure-sensitive material 102 will increase correspondingly, which means that the distribution between the conductive materials becomes thinner, resulting in a reduction in the conductivity of the conductive materials. , and then the electrical signal inside the pressure-sensitive material 102 changes accordingly (for example, the resistance of the pressure-sensitive material 102 increases accordingly). Therefore, by measuring the change of the electrical signal of the pressure-sensitive material 102 , the relationship (for example, a linear relationship) between the magnitude of the external pressure can be obtained. In addition, the magnitude of the pressure applied by the outside can be obtained by measuring the sum of electrical signals of a plurality of pressure-sensitive materials 102 to improve measurement accuracy and sensitivity. Reducing the contact resistance can avoid the deviation of the relationship between the electrical signal and the external pressure, and improving the consistency of the electrode set 500 can help reduce the resistance tolerance. Therefore, reducing the contact resistance or improving the consistency of the electrode set 500 can enhance the sensing accuracy of the pressure sensing device.

Based on the above, the embodiments of the present disclosure provide a pressure sensing device and a manufacturing method thereof. By laminating the first flexible base material with the pressure-sensitive material and the second flexible base material with the electrode group, the pressure-sensitive material and the second flexible base material are combined. After pressing, the electrode groups are electrically connected to each other and form good contact resistance. In addition, the electrode group of this disclosure is made of the same hole, thereby improving the consistency of the distance length of each electrode in the electrode group, and improving the process yield through the precision control of the hole, thereby reducing the cost of different electrode groups. the tolerance between. Thereby, the sensing accuracy of the pressure sensing device is improved.

The features of several embodiments of the present disclosure are briefly described above, so that those skilled in the art can understand the present disclosure more easily. Those skilled in the art should understand that this specification can be easily used as a basis for other structural or process changes or designs to achieve the same purpose and/or obtain the same advantages as the embodiments of the present disclosure. Anyone with ordinary knowledge in the technical field can also understand that the structure equivalent to the above does not depart from the spirit and protection scope of the disclosure, and can be modified, substituted and Revise.

100: the first soft substrate 102: Pressure sensitive material 200: the second soft substrate 202: line layer 400: conductive layer

400-1: Part I

400-2: Part Two

400-3: Part Three

400-4: Part Four

500: electrode group

500-1: first electrode

500-2: Second electrode

510: Reference symmetry axis

600: The third soft substrate

602: Glue

700: protective layer

702: Pressure sensing device

D-1: first distance

D-2: second distance

O1: first opening

O2: second opening

R: cutting area

S1: first surface

S2: second surface

S100: step

S200: Steps

S300: Steps

S400: Steps

S500: Steps

S600: Steps S700: Steps A-A: Sectional line

When reading the following implementation methods with accompanying drawings, the viewpoints of the disclosure can be clearly understood. It should be noted that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily expanded or reduced for clarity of discussion. Again, the same reference numerals denote the same elements. 1A, 2A, 3A, 4A, 5A, 6A, and 7A are top views illustrating various stages of fabrication of pressure sensing devices according to some embodiments of the present disclosure. Figures 1B, 2B, 3B, 4B, 5B, 6B, and 7B are top view cross-sections of pressure sensing devices at various stages of fabrication according to some embodiments of the disclosure. Sectional view of line A-A.

Domestic deposit information (please note in order of depositor, date, and number) none Overseas storage information (please note in order of storage country, institution, date, and number) none

100: the first soft substrate

102: Pressure sensitive material

200: the second soft substrate

202: line layer

500: electrode group

500-1: first electrode

500-2: Second electrode

600: The third soft substrate

602: Glue

700: protective layer

702: Pressure sensing device

S1: first surface

S2: second surface

S700: Steps

Claims (17)

A pressure sensing device, comprising: a first flexible substrate; a pressure-sensitive material disposed on the first flexible substrate; a second flexible substrate disposed on the pressure-sensitive material, comprising: a first a surface facing the pressure-sensitive material; a second surface opposite to the first surface; and an opening extending to the first surface and the second surface; and an electrode group disposed in the opening and extending from the The opening extends to the first surface and the second surface, wherein the electrode group is electrically connected to the pressure-sensitive material, and includes: a first electrode covering part of the inner surface of the opening, part of the first surface and part of the second Two surfaces; and a second electrode covering a part of the inner surface of the opening, a part of the first surface and a part of the second surface, wherein the second electrode and the first electrode are arranged opposite to and separated from each other. The pressure sensing device according to claim 1, wherein in a plan view of the pressure sensing device viewed from the second surface, the first electrode and the second electrode exhibit mirror symmetry. The pressure sensing device according to claim 1, wherein the first electrode has a first concave surface, and the second electrode has a second concave surface, and the first concave surface and the second concave surface face each other. The pressure sensing device as claimed in claim 1, wherein the pressure-sensitive material includes: an elastic resin; and a plurality of conductive materials distributed in the elastic resin. The pressure sensing device as claimed in claim 4, wherein the plurality of conductive materials include silver. The pressure sensing device as claimed in claim 5, wherein the plurality of conductive materials further include tin or bismuth. The pressure sensing device as claimed in claim 1, wherein the material of the electrode group includes tin or silver. The pressure sensing device as claimed in claim 1, wherein the electrode group disposed on the first surface of the second flexible substrate directly contacts the pressure-sensitive material. The pressure sensing device according to claim 1, further comprising: a protective layer, filled in the opening of the second flexible substrate, and distributed between the first electrode and the second electrode. The pressure sensing device as claimed in claim 9, wherein the electrode group disposed on the inner surface of the opening directly contacts the protective layer. A method for manufacturing a pressure sensing device, comprising: providing a first flexible substrate; disposing a pressure-sensitive material on the first flexible substrate; providing a second flexible substrate, including a first surface and a second surface, wherein the first surface is opposite to the second surface; forming an opening in the second flexible substrate, wherein the opening extends to the first surface and the second surface; forming a conductive layer in the opening On the surface and on the first surface, wherein the conductive layer has a continuous edge in a top view viewed from the second surface; removing a first portion of the conductive layer and a second portion opposite to the first portion part, so that the continuous edge of the conductive layer is disconnected to separate a first electrode and a second electrode; and pressing the first flexible substrate and the second flexible substrate, so that the pressure-sensitive material is electrically connected The first electrode and the second electrode, wherein the pressure-sensitive material is interposed between the first flexible substrate and the second flexible substrate. The method of manufacturing a pressure sensing device as claimed in claim 11, wherein after removing the first part and the second part, in the top view viewed from the second surface, the first electrode and the first electrode The two electrodes exhibit mirror symmetry. The method of manufacturing a pressure sensing device as claimed in claim 11, wherein forming the conductive layer includes using an electroplating process. The method for manufacturing a pressure sensing device according to claim 11, further comprising: before laminating the first flexible substrate and the second flexible substrate, forming a silver layer or a tin layer on the first electrode and the second flexible substrate on the second electrode. The method for manufacturing a pressure sensing device as claimed in claim 11, wherein the lamination temperature of the first flexible substrate and the second flexible substrate is between 180 degrees Celsius and 260 degrees Celsius. The method for manufacturing a pressure sensing device according to claim 11, wherein the first flexible substrate and the second flexible substrate are pressed together so that both the first electrode and the second electrode directly contact the pressure-sensitive material. The method for manufacturing a pressure sensing device as claimed in claim 11, further comprising: forming a protective layer on the second flexible substrate, wherein the protective layer is distributed between the first electrode and the second electrode.

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