A metal strain sensing device and its manufacturing method and use method

Abstract

The present invention belongs to the technical field related to micro-nano optomechanical systems, and discloses a metal strain sensing device and a manufacturing method and a use method thereof. The metal strain sensing device includes a flexible and stretchable structure, which includes a silicon grating substrate and a metal film layer formed on the silicon grating substrate. The silicon grating substrate is a flexible and stretchable substrate, which has stretchability and bendability; the metal strain sensing device is formed with a strain sensing area, and the resistance value of the strain sensing area changes with the change of the strain value of the metal sensing device; the metal strain sensing device realizes the measurement of the strain amount through its own resistance change. The metal strain sensing device provided by the present invention has stretchability and bendability, reduces the preparation cost, and improves the efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field related to Wiener optomechanical systems, and more specifically, relates to a metal strain sensing device based on a flexible stretchable grating substrate, and a manufacturing method and a use method thereof. Background Art

[0002] Strain sensing devices are made based on the principle that when a semiconductor or semiconductor material is mechanically deformed under the action of external forces, its resistance value changes accordingly. At present, fiber grating sensors are widely used to measure strain, but fiber gratings are generally too thin and brittle and cannot be bent, which brings a lot of inconvenience to practical use.

[0003] At present, relevant technical personnel in this field have done some research. For example, patent CN106441376A discloses a graphite grid flexible resistance strain gauge and its manufacturing method. The graphite grid flexible resistance strain gauge can produce a large deformation, high precision, and relatively simple manufacturing. However, the graphite grid flexible resistance strain gauge does not have stretchability and has poor applicability. Accordingly, there is a technical demand in this field to develop a stretchable metal strain sensing device and its manufacturing method and use method. Summary of the invention

[0004] In view of the above defects or improvement needs of the prior art, the present invention provides a metal strain sensing device and a manufacturing method and a use method thereof. Based on the working characteristics of the existing strain sensing device, a stretchable metal strain sensing device and a manufacturing method and a use method thereof are studied and designed. The metal strain sensing device is formed by replicating a flexible stretchable material on a silicon grating template and sputtering a metal film layer. This method can give full play to the stretchability and bendability of the grating substrate, can accurately measure the resistance change of the metal strain sensing device caused by external strain, and has a low preparation cost, high efficiency and can be replicated and produced in batches.

[0005] To achieve the above object, according to one aspect of the present invention, a metal strain sensing device is provided, wherein the metal strain sensing device is a flexible and stretchable structure, comprising a silicon grating substrate and a metal film layer formed on the silicon grating substrate, wherein the silicon grating substrate is a flexible and stretchable substrate having stretchability and bendability;

[0006] The metal strain sensing device is formed with a strain sensing area, and the resistance value of the strain sensing area changes with the change of the strain value of the metal sensing device; the metal strain sensing device realizes the measurement of the strain amount through the change of its own resistance.

[0007] Furthermore, the silicon grating substrate is formed with a plurality of gratings arranged at intervals, and the gratings are located in the strain sensing area.

[0008] Furthermore, the thickness of the metal film layer is 10 nanometers to 10000 nanometers.

[0009] Furthermore, the material of the metal thin film layer is any one of Au, Ag, Al, Cu, Pt and Cr.

[0010] According to another aspect of the present invention, a method for manufacturing the metal strain sensing device as described above is provided, the manufacturing method comprising the following steps:

[0011] (1) preparing a silicon grating template and performing a hydrophobic treatment on the silicon grating template;

[0012] (2) placing the silicon grating template on the molding area of ​​the prepared contour forming mold, spin coating the uncured flexible stretchable material solution on the silicon grating template and curing it; then, peeling off the obtained sample to obtain the silicon grating substrate;

[0013] (3) The metal thin film layer is deposited on the silicon grating substrate, thereby obtaining the metal strain sensing device.

[0014] Furthermore, in step (1), the prepared silicon grating template is placed in hydrophobic silane and immersed for 5 minutes to 15 minutes, so that the surface of the silicon grating template is changed into a hydrophobic surface.

[0015] Furthermore, the flexible stretchable material includes one of PDMS material, PMMA material and sulfide glass.

[0016] Furthermore, the curing in step (2) is performed at a temperature of 50° C. to 200° C. for 5 minutes to 120 minutes.

[0017] The present invention also provides a method for using the metal strain sensing device as described above, the method comprising the following steps:

[0018] (1) Connect the two ends of the metal strain sensing device to a resistance measuring instrument and record the initial resistance value R of the metal strain sensing device. 0 ;

[0019] (2) the resistance measuring instrument records the real-time resistance value R of the metal strain sensing device when it is acted upon by an external force F, and the strain measuring instrument is used to record the real-time strain value S of the metal strain sensing device;

[0020] (3) A relationship between the strain S and the corresponding real-time resistance change value ΔR is established, and then the strain of the object to be measured is obtained by combining the relationship and the corresponding resistance change value.

[0021] Furthermore, the relationship is:

[0022] ΔR=RR 0 =f(S) (1).

[0023] In general, compared with the prior art, the metal strain sensing device and its manufacturing method and use method provided by the present invention have the following beneficial effects:

[0024] 1. The metal strain sensing device is a flexible and stretchable structure, which includes a silicon grating substrate and a metal film layer formed on the silicon grating substrate. It successfully solves the shortcomings of traditional strain gauges that are not flexible and stretchable. It has high bendability and stretchability, and provides a basis for the application of flexible and stretchable strain sensing devices in the fields of flexible optoelectronics, intelligent sensing devices, etc.

[0025] 2. The metal strain sensing device adopts relevant materials and process solutions based on nano-replication molding, which takes a short preparation time and is low in cost.

[0026] 3. The silicon grating substrate is formed with a plurality of gratings arranged at intervals, and the gratings are located in the strain sensing area. The strain sensing area adopts a grating structure, which can reduce the fatigue loss caused by the strain effect on the metal strain sensing device, and at the same time, increase the detection accuracy of a small strain range.

[0027] 4. The silicon grating substrate is a flexible and stretchable substrate, which has stretchability and bendability. When deformation occurs due to external forces, the structural deformation of the metal strain sensing device will be reflected in the change of the output resistance value of the metal strain sensing device. The external strain can be detected in real time through the change information of the resistance value. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the structure of the metal strain sensing device provided by the present invention.

[0029] Figure 2 yes Figure 1 Schematic diagram of the metal strain sensing device from another angle.

[0030] Figure 3 yes Figure 1 Schematic diagram of the process of manufacturing the metal strain sensing device.

[0031] Figure 4 yes Figure 3 A schematic diagram of a contour forming die involved in a method for manufacturing a metal strain sensing device.

[0032] Figure 5 Is adopted Figure 1The strain response diagram of the metal strain sensing device is obtained by using the method of using the metal strain sensing device.

[0033] In all drawings, the same reference numerals are used to denote the same elements or structures, wherein: 6 - strain sensing area, 7 - first clamping portion, 8 - second clamping portion, 9 - silicon grating template, 10 - hydrophobic layer, 11 - contour forming mold, 12 - molding area. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0035] See also Figure 1 and Figure 2 The metal strain sensing device provided by the present invention is basically in an I-shaped shape, and includes a silicon grating substrate and a metal film layer formed on the silicon grating substrate. The silicon grating substrate is a flexible and stretchable substrate, which has stretchability and bendability. The silicon grating substrate has a plurality of gratings, and the plurality of gratings are arranged at intervals. Figure 1 , Figure 1 Here, 1 represents the thickness of the silicon grating substrate, 2 represents the thickness of the metal film layer, 3 represents the period length of the grating, the width is shown as 4, and the height is shown as 5.

[0036] In this embodiment, a strain sensing area 6 is formed in the middle of the metal strain sensing device, and the grating is located in the strain sensing area 6. The resistance value of the strain sensing area 6 changes with the change of the strain value, and the stress strain value is accurately calculated by measuring the resistance value in real time. The metal strain sensing device senses the strain in the external physical quantity through the deformation of the geometric structure, and measures the corresponding variable with high sensitivity through the change of its own resistance value. The metal strain sensing device is flexible and stretchable, and a first clamping part 7 and a second clamping part 8 are formed at its two ends, respectively, and the first clamping part 7 and the second clamping part 8 are respectively connected to the strain sensing area 6. When in use, the metal strain sensing device is connected to the object to be detected through the first clamping part 7 and the second clamping part 8.

[0037] See also Figure 3 and Figure 4 The manufacturing method of the metal strain sensing device provided by the present invention comprises the following steps:

[0038] (1) Preparation of silicon grating template: After selecting parameters such as grating period, grating height and duty cycle, the silicon grating template 9 is prepared by electron beam etching or deep ultraviolet etching.

[0039] (2) Surface hydrophobic treatment of silicon grating template: Specifically, the prepared silicon grating template 9 is immersed in hydrophobic silane for 5 to 15 minutes, so that the surface property of the silicon grating template 9 is changed to a hydrophobic surface, thereby obtaining a surface hydrophobic layer 10 .

[0040] (3) Preparing a contour forming die. Specifically, the length and width of the metal strain sensing device and the size of the strain sensing area 6 are set, and a corresponding contour forming die 11 is prepared using a resin material, wherein the contour forming die 11 is formed with a forming area 12. The contour forming die is consistent with the shape of the metal strain sensing device.

[0041] (4) Configure a flexible stretchable material. Specifically, the flexible stretchable material has deformation capabilities such as bending and stretching, and is a type of elastic-plastic material that meets the requirements of the nano-replication molding process. In this embodiment, taking PDMS material as an example, the uncured PDMS and the curing agent are mixed in a predetermined volume ratio and stirred so that the uncured PDMS material and the curing agent are evenly mixed; finally, the resulting mixed liquid is placed in a vacuum box for degassing for a predetermined time. Among them, the predetermined volume ratio is 1:15 to 1:3; the predetermined time is 10 minutes to 60 minutes. In other embodiments, the flexible stretchable material can also be PMMA, sulfide glass, etc.

[0042] (5) Making a silicon grating substrate. After placing the prepared silicon grating template 9 on the molding area 12 of the contour forming mold 11, the uncured PDMS solution is spin-coated in the filling area of ​​the silicon grating template 9 to form the silicon grating substrate; then, the obtained sample is placed in an oven and cured at a temperature of 50°C to 200°C for 5 minutes to 120 minutes.

[0043] (6) Peeling off the silicon grating substrate. Specifically, the cured PDMS sample cured on the contour forming mold 11 is peeled off from the contour forming mold 11; then, the silicon grating template 9 is peeled off to obtain a flexible and stretchable silicon grating substrate.

[0044] (7) Preparing a metal film layer. Specifically, the metal film is deposited on the silicon grating substrate by electron beam evaporation or magnetron sputtering, thereby manufacturing a metal strain sensing device based on a flexible and stretchable substrate. In this embodiment, the material of the metal film layer is any one of Au, Ag, Al, Cu, Pt and Cr; the thickness of the metal film layer is 10 nanometers to 10000 nanometers.

[0045] See also Figure 5 The present invention also provides a method for using the metal strain sensing device as described above, the method comprising the following steps:

[0046] (1) Fix the metal strain sensing device at both ends of the stretching mechanism, connect the two ends of the metal strain sensing device to a resistance measuring instrument, and record the initial resistance value R of the metal strain sensing device. 0 .

[0047] (2) The resistance measuring instrument records the real-time resistance value R of the metal strain sensing device when it is acted upon by an external force F, and a high-precision strain measuring instrument is used to record the real-time strain value S of the metal strain sensing device.

[0048] (3) Establish a relationship between the strain S and the corresponding real-time resistance change value ΔR, so that the strain under the actual environmental state is obtained through the real-time resistance change value and the relationship. Specifically, the relationship is shown in formula (1):

[0049] ΔR=RR 0 =f(S) (1)

[0050] The resistance value of the metal strain sensing device obtained by the above method changes with the change of the strain amount, and there is a linear regularity in the strain range of 0-25%.

[0051] The metal strain sensing device provided by the present invention and its manufacturing method and use method can sense the strain in the external physical quantity through the geometric structural deformation of the stretchable grating substrate and the metal film layer on its upper surface, and measure the corresponding variable with high sensitivity through the change of the resistance value of the metal strain sensing device. In addition, the metal strain sensing device is flexible and stretchable, which is conducive to the wide application in the fields of intelligent perception, intelligent medical treatment, etc.

[0052] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A metal strain sensing device, characterized in that: The metal strain sensing device is a flexible and stretchable structure, which includes a silicon grating substrate and a metal film layer formed on the silicon grating substrate, and the silicon grating substrate is a flexible and stretchable substrate, which has stretchability and bendability; The metal strain sensing device is formed with a strain sensing area, and the resistance value of the strain sensing area changes with the strain value of the metal strain sensing device; the metal strain sensing device realizes the measurement of the strain amount through its own resistance change; the silicon grating substrate is formed with a plurality of gratings arranged at intervals, and the gratings are located in the strain sensing area.

2. The metal strain sensing device according to claim 1, characterized in that: The thickness of the metal film layer is 10 nanometers to 10000 nanometers.

3. The metal strain sensing device according to any one of claims 1 to 2, characterized in that: The material of the metal thin film layer is any one of Au, Ag, Al, Cu, Pt and Cr.

4. A method for manufacturing a metal strain sensing device according to any one of claims 1 to 3, characterized in that: The method comprises the following steps: (1) preparing a silicon grating template and performing a hydrophobic treatment on the silicon grating template; (2) placing the silicon grating template on the molding area of ​​the prepared contour forming mold, spin coating the uncured flexible stretchable material solution on the silicon grating template and curing it; then, peeling off the obtained sample to obtain the silicon grating substrate; (3) The metal thin film layer is deposited on the silicon grating substrate, thereby obtaining the metal strain sensing device.

5. The method for manufacturing a metal strain sensing device according to claim 4, characterized in that: In step (1), the prepared silicon grating template is placed in hydrophobic silane and immersed for 5 minutes to 15 minutes, so that the surface of the silicon grating template is changed into a hydrophobic surface.

6. The method for manufacturing a metal strain sensing device according to claim 4, characterized in that: The flexible and stretchable material includes one of PDMS material, PMMA material and sulfide glass.

7. The method for manufacturing a metal strain sensing device according to claim 4, characterized in that: The curing in step (2) is carried out at a temperature of 50°C to 200°C for 5 minutes to 120 minutes.

8. A method for using the metal strain sensing device according to any one of claims 1 to 3, characterized in that: The method of use includes the following steps: (1) Connect the two ends of the metal strain sensing device to a resistance measuring instrument and record the initial resistance value R of the metal strain sensing device. o ; (2) the resistance measuring instrument records the real-time resistance value R of the metal strain sensing device when it is acted upon by an external force F, and the strain measuring instrument is used to record the real-time strain value S of the metal strain sensing device; (3) Establishing a relationship between the strain S and the corresponding real-time resistance change value ΔR, and then combining the relationship and the corresponding resistance change value to obtain the strain of the object under test.

9. The method for using the metal strain sensing device according to claim 8, characterized in that: The relationship is: ΔR=R-R0=f(S) (1).

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