CN110526198B - Flexible pressure sensor based on hemispherical microstructure and manufacturing method thereof - Google Patents
Flexible pressure sensor based on hemispherical microstructure and manufacturing method thereof Download PDFInfo
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B81—MICROSTRUCTURAL TECHNOLOGY
- B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
- B81B3/00—Devices comprising flexible or deformable elements, e.g. comprising elastic tongues or membranes
- B81B3/0018—Structures acting upon the moving or flexible element for transforming energy into mechanical movement or vice versa, i.e. actuators, sensors, generators
- B81B3/0027—Structures for transforming mechanical energy, e.g. potential energy of a spring into translation, sound into translation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B81—MICROSTRUCTURAL TECHNOLOGY
- B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
- B81C1/00—Manufacture or treatment of devices or systems in or on a substrate
- B81C1/00349—Creating layers of material on a substrate
- B81C1/0038—Processes for creating layers of materials not provided for in groups B81C1/00357 - B81C1/00373
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B81—MICROSTRUCTURAL TECHNOLOGY
- B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
- B81C1/00—Manufacture or treatment of devices or systems in or on a substrate
- B81C1/00388—Etch mask forming
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B81—MICROSTRUCTURAL TECHNOLOGY
- B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
- B81B2201/00—Specific applications of microelectromechanical systems
- B81B2201/02—Sensors
- B81B2201/0264—Pressure sensors
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- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Manufacturing & Machinery (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Computer Hardware Design (AREA)
- Measuring Fluid Pressure (AREA)
- Pressure Sensors (AREA)
Abstract
The invention is applicable to the technical field of flexible pressure sensors, and discloses a flexible pressure sensor based on a hemispherical microstructure and a manufacturing method thereof. The flexible pressure sensor comprises a PDMS flexible substrate layer, a carbon nanotube film and a PDMS flexible film layer, wherein the PDMS flexible substrate layer is provided with a microstructure, the microstructure is in a spherical protrusion shape, one surface of the PDMS flexible substrate layer provided with the microstructure is covered with the carbon nanotube film, the carbon nanotube film is positioned between the PDMS flexible substrate layer and the PDMS flexible film layer, and the carbon nanotube film is connected with an electrode. The manufacturing method is used for manufacturing the flexible pressure sensor. The flexible pressure sensor based on the hemispherical microstructure and the manufacturing method thereof provided by the invention have the advantages that the measuring range and the sensitivity of the flexible pressure sensor are improved, and the response time is reduced.
Description
Technical Field
The invention belongs to the technical field of flexible pressure sensors, and particularly relates to a flexible pressure sensor based on a hemispherical microstructure and a manufacturing method thereof.
Background
Along with the development of society, flexible sensing devices bring revolutionary changes to a plurality of aspects of social life, and are gradually applied to the fields of robots, wearable electronic equipment, man-machine interaction, intelligent skins and the like due to the advantages of the flexible sensing devices in the aspect of flexibility. Compared with the traditional sensor, the flexible sensor has a plurality of defects in performance, and the flexible sensor at present has the problems of low sensitivity, small measuring range, large hysteresis, easiness in interference of external environment noise and the like.
In recent years, with economic rapid expansion, the life quality of people is greatly improved, rapid development of wearable flexible sensors is promoted, and people hope to wear the sensing devices on the body comfortably or directly attach the sensing devices to the skin surface, so that health information such as pulse and blood pressure can be acquired. In addition, the flexible sensor is also an important component for the human bionic artificial limb and the intelligent robot to sense the external environment. The research of the flexible pressure sensor becomes a research hot spot in the recent year, and the former adopts various different means to improve the performance indexes of the flexible pressure sensor, such as sensitivity, measuring range, repeatability, consistency and the like, so that the application field of the flexible pressure sensor is expanded.
In recent years, the process of manufacturing flexible pressure sensors mainly includes the following steps:
1. And manufacturing a pyramid groove array die through photoetching and wet etching, pouring PDMS into the die to manufacture a PDMS substrate with a pyramid structure, then preparing graphene oxide suspension, manufacturing a graphene film on the PDMS film with the pyramid structure by adopting a layer-by-layer self-assembly method, finally attaching the PDMS film with the graphene to the PET film with the ITO coating, and leading out an electrode on the film to finish the manufacture of the flexible pressure sensor. The pressure sensor can measure a pressure of 1.5Pa at minimum, the response time is only 0.2 milliseconds, and the sensitivity is-5.53/kPa over the pressure range of 0 to 100 Pa.
2. A rail wafer mold with pyramidal grooves is fabricated using photolithographic techniques. And 5:1 and the cross-linking agent are mixed in proportion, and then diluted with hexane and stirred for more than 30 minutes. Coating 100 microliters of diluted solution on a die, degassing, treating a 150 micrometer thick PET film with an ITO conductive layer by ultraviolet rays for 20 minutes, then placing the PET film on a PDMS film in a vacuum environment, applying at least 100MPa to the film in the environment of 70 ℃ for stacking for 4 hours, and finally connecting leads at two ends of the film to prepare the sensor. Since the sensor has an array of microstructures that are easily deformable, a measurement with high sensitivity is achieved, up to 0.55/kPa in the range of 2 kPa.
3. 10, 30, 50 Mg of single-walled carbon nanotube (SWCNT) powder was mixed with 10mL of deionized water to prepare SWCNT solutions of different concentrations, followed by mixing 0.1 mL of Polystyrene (PSS) solution for 30 minutes of sonication. And pouring the PDMS solution into a mould to prepare a PDMS film with the thickness of 500 microns, and treating the PDMS surface by adopting oxygen plasma to obtain a hydrophilic surface. The 100nm thick PU-PEDOT: PSS composite elastomer layer was mixed from a solution of polyurethane (60% by weight) and PEDOT: PSS (40% by weight) and deposited on the substrate. Annealing at 150 degrees celsius for one hour, self-assembled (SAM) of the composite film surface with a triethoxysilane solution was performed for 30 minutes to obtain a SWCNT solution coating on the PDMS substrate. After the SAM treatment, the SWCNT solution was dropped on the substrate surface and spin-coated at 1000rpm for 10 minutes to obtain a film having a thickness of 1.2 μm. The sample was then annealed at 100 degrees celsius for 1 hour. Finally, a layer of PU/PEDOT/PSS solution is coated and annealed at 100 ℃ for one hour, so that the preparation of the sensor is completed. The sensor has high transparency, can reach 72% transparency, has good repeatability and has sensitivity coefficient reaching 106.
4. 44Mg of trichloracetic acid trihydrate is added to 40ml of hexane, followed by 1.5ml of oleylamine, and after complete dissolution of the gold salt, 2.1 ml of triisopropylsilane are added to the above solution. The mixed solution was allowed to stand at room temperature for two days, knowing that the color of the solution changed from yellow to dark red, indicating the formation of gold nanowires. Centrifugation and washing were performed multiple times with a mixed solution of ethanol and hexane (volume ratio 2:1) to remove the residual compound, and finally concentrated into 2ml of chloroform solution. A tissue of Kimberly (Kimberly Clark) 8×8mm2 was soaked in a chloroform solution of gold nanowires, and after chloroform evaporation, the tissue color changed from white to dark red. The staggered Ti/Au electrodes were plated on a PDMS substrate of 30x27mm2 by repeating the application and drying approximately ten times until the electrical resistance of the tissue reached 2.5mΩ/sq. The spacing between adjacent electrodes is typically 0.1 mm and the intermediate electrode spacing is 0.5 mm. Two 10x10mm2 contact plates are placed between the two electrodes at both ends to connect to external circuitry. Finally, the PDMS film with staggered electrodes and the blank PDMS film are used for wrapping the film with AuNWs in the middle, so that the structure with the same sandwich is formed. The sensor obtained by the method can measure very small pressure, has corresponding time of 17ms and sensitivity of 1.14/kPa, and can realize real-time measurement of human pulse.
Although the flexible sensor described above may enable measurement of ambient pressure, there are some drawbacks.
1. The flexible pressure sensor based on the graphene microstructure array has lower sensitivity in an excessively high or excessively low pressure range. Resulting in a smaller range of applications.
2. The sensitivity of the flexible sensor based on the microstructure rubber dielectric layer is relatively low, and the flexible sensor is only suitable for sensing static pressure.
3. The flexible sensor based on the piezoresistive effect has response lag under a larger stretching amount, and is difficult to restore.
4. The gold nanowire-based flexible pressure sensor has lower transparency, and the sensor has lower sensitivity under larger stretching amount and even fails due to breakage of the electrode.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a flexible pressure sensor based on a hemispherical microstructure and a manufacturing method thereof, which improve the measurement range and sensitivity of the flexible pressure sensor and reduce the response time.
The technical scheme of the invention is as follows: the utility model provides a flexible pressure sensor based on hemisphere micro-structure, includes PDMS flexible substrate layer, carbon nanotube film and PDMS flexible film layer, PDMS flexible substrate layer has the microstructure, the microstructure is the sphere bulge form, PDMS flexible substrate layer has the one side of microstructure is covered with carbon nanotube film, just carbon nanotube film is located PDMS flexible substrate layer with between the PDMS flexible film layer, the carbon nanotube film is connected with the electrode.
Optionally, the microstructure is hemispherical.
The invention also provides a manufacturing method of the flexible pressure sensor, which comprises the following steps:
Preparing a PDMS flexible substrate layer with a microstructure in a spherical bulge shape;
Preparing a carbon nano tube film;
Covering the carbon nano tube film on the surface of the PDMS flexible substrate layer with the microstructure;
Preparing a PDMS flexible film layer and covering the PDMS flexible film layer on the carbon nanotube film;
And connecting an electrode with the carbon nano tube film.
Optionally, wherein preparing the PDMS flexible substrate layer comprises the steps of:
Manufacturing a silicon wafer mold with a hemispherical groove structure by adopting a photoetching technology;
Mixing and stirring PDMS and a cross-linking agent in a weight ratio of 10:1 to obtain a mixed solution, and then coating the mixed solution on the silicon wafer mold with the hemispherical grooves;
heating the silicon wafer mold and the mixed solution;
And cooling the silicon wafer mold and the mixed solution, cooling and solidifying the mixed solution to form a PDMS flexible substrate layer, and separating the PDMS flexible substrate layer from the silicon wafer mold to obtain the PDMS flexible substrate layer with a hemispherical microstructure.
Optionally, the preparation of the carbon nanotube film includes the following steps:
Step one: mixing hydrogen chloride with hydrogen peroxide solution to obtain mixed solution, adding carbon nanotube powder into the mixed solution, and heating;
Step two: and (3) adding the carbon nano tube in the step (I) into dimethylformamide solution, vacuumizing and leaking to obtain a layer of carbon nano tube film attached to the leaking film.
Step three: and (3) obliquely inserting the seepage film into deionized water, and separating a layer of carbon nanotube film from the carbon nanotube film obtained in the step (II).
Step four: the carbon nanotube film floating on deionized water was taken out and air-dried with a nitrogen stream.
Optionally, in the third step, a layer of the carbon nanotube film having a thickness of 50-60nm is separated from the carbon nanotube film having a thickness of 200-300 μm.
Optionally, covering the carbon nanotube film on the surface of the PDMS flexible substrate layer having the microstructure includes the following steps:
the carbon nanotube film was transferred onto a PDMS flexible substrate layer having a hemispherical microstructure and heated.
Optionally, the preparing the PDMS flexible film layer includes the steps of:
mixing and stirring PDMS and a cross-linking agent in a weight ratio of 10:1 to obtain a solution;
The solution is spin-coated on a silicon wafer, heated, cooled and separated from the semi-cured PDMS flexible film layer on the silicon wafer.
Optionally, a semi-cured PDMS flexible film layer is bonded to the carbon nanotube film and the PDMS flexible substrate layer and heated.
Optionally, electrodes are led out on both sides of the carbon nanotube film of the intermediate layer after bonding.
According to the flexible pressure sensor based on the hemispherical microstructure and the manufacturing method thereof, the hemispherical internal structure is adopted in the flexible pressure sensor, the measuring range of the sensor is greatly improved, the sensor is provided with higher sensitivity by combining the carbon nano tube with high conductivity, and the manufacturing method is improved, so that the flexible sensor is simpler and more feasible to manufacture, the manufacturing difficulty is reduced, the labor cost is reduced, the manufacturing efficiency is improved, and the standardized manufacturing process is realized.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic cross-sectional view of a flexible pressure sensor based on hemispherical microstructures provided by an embodiment of the present invention;
FIG. 2 is a schematic cross-sectional view of a silicon wafer mold used in a method of manufacturing a flexible pressure sensor according to an embodiment of the present invention;
FIG. 3 is a schematic plan view of a silicon wafer mold used in a method of manufacturing a flexible pressure sensor according to an embodiment of the present invention;
fig. 4 is a reference flowchart of a method for manufacturing a flexible pressure sensor according to an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
It will be understood that when an element is referred to as being "mounted" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or intervening elements may also be present.
It should be noted that, in the embodiments of the present invention, terms such as left, right, up, and down are merely relative concepts or references to normal use states of the product, and should not be construed as limiting.
As shown in FIG. 1, the flexible pressure sensor based on the hemispherical microstructure provided by the embodiment of the invention comprises a PDMS flexible substrate layer 1, a carbon nano tube film 2 and a PDMS flexible film layer 3, wherein the PDMS flexible substrate layer 1 and the PDMS flexible film layer 3 are made of PDMS, PDMS (polydimethyl siloxane) is English abbreviation of polydimethylsiloxane, has high transparency, has good adhesion with a silicon wafer, has good chemical inertness, has good light transmittance, good biocompatibility, is easy to be combined with various materials at room temperature, and has high elasticity due to low Young modulus. The PDMS flexible substrate layer 1 has microstructures 11, the microstructures 11 being spherically convex, i.e. the microstructures 11 may be spherical crowns, preferably the microstructures 11 may be hemispherical. The plurality of microstructures 11 are provided, and the plurality of microstructures 11 are integrally formed on one surface of the PDMS flexible substrate layer 1 in a matrix shape. One surface of the PDMS flexible substrate layer 1 having the microstructure 11 is covered with the carbon nanotube film 2, and the carbon nanotube film 2 is uniformly and closely covered on the microstructure 11 and the PDMS flexible substrate layer 1. And the carbon nano tube film 2 is positioned between the PDMS flexible substrate layer 1 and the PDMS flexible film layer 3, and the carbon nano tube film 2 is connected with an electrode. The working principle of the flexible sensor is piezoresistance effect, when the external environment applies load to the flexible sensor, the internal hemispherical microstructure 11 deforms, the contact area between the hemispherical microstructure 11 and the substrate is reduced, so that the resistance of the flexible pressure sensor is reduced, and the current intensity is increased. And after the load is released, the hemispherical microstructure 11 is restored to the original state due to the elastic characteristic of the PDMS, so that the flexible pressure sensor can realize pressure measurement by measuring current, and the measuring range and sensitivity of the flexible pressure sensor are improved, and the response time is shortened.
The embodiment of the invention also provides a manufacturing method of the flexible pressure sensor, which can be used for preparing the flexible pressure sensor based on the hemispherical microstructure, and comprises the following steps of:
preparing a PDMS flexible substrate layer 1 with a microstructure 11 in the shape of a spherical bulge;
Preparing a carbon nanotube film 2;
covering the carbon nanotube film 2 on the surface of the PDMS flexible substrate layer 1 with the microstructure 11;
preparing a PDMS flexible film layer 3 and covering the PDMS flexible film layer 3 on the carbon nanotube film 2;
and connecting an electrode to the carbon nanotube film 2.
Specifically, the preparation of the PDMS flexible substrate layer 1 comprises the following steps:
As shown in fig. 2 and 3, a silicon wafer mold 4 having a hemispherical groove structure 41 is manufactured using a photolithography technique, and the hemispherical groove structure 41 may be used to form the hemispherical microstructure 11;
mixing and stirring PDMS and a cross-linking agent in a weight ratio of 10:1 to obtain a mixed solution, and then coating the mixed solution on the silicon wafer mold 4 with the hemispherical grooves 41;
heating the silicon wafer mold 4 and the mixed solution;
And cooling the silicon wafer mold 4 and the mixed solution, forming the PDMS flexible substrate layer 1 after cooling and solidifying the mixed solution, and separating the PDMS flexible substrate layer 1 from the silicon wafer mold 4 to obtain the PDMS flexible substrate layer 1 with the hemispherical microstructure 11.
Specifically, the preparation of the carbon nanotube film 2 includes the following steps:
Step one: mixing hydrogen chloride with hydrogen peroxide solution to obtain mixed solution, adding carbon nanotube powder into the mixed solution, and heating;
step two: and (3) adding the carbon nano tube in the step one into dimethylformamide solution, vacuumizing and leaking to finally obtain a layer of carbon nano tube film 2 attached to the leaking film.
Step three: and (3) obliquely inserting the seepage film into deionized water, and separating one layer of carbon nanotube film 2 from the carbon nanotube film 2 obtained in the step (II).
Step four: the carbon nanotube film 2 floating on deionized water was taken out and air-dried with a nitrogen stream.
Specifically, in the third step, a layer of the carbon nanotube film 2 having a thickness of 50-60nm is separated from the carbon nanotube film 2 having a thickness of 200-300 μm.
Specifically, the surface of the PDMS flexible substrate layer 1 having the microstructure 11 is covered with the carbon nanotube film 2, which comprises the following steps:
The carbon nanotube film 2 is transferred onto the PDMS flexible substrate layer 1 having the hemispherical microstructure 11 and then heated.
Specifically, the preparation of the PDMS flexible film layer 3 includes the following steps:
mixing and stirring PDMS and a cross-linking agent in a weight ratio of 10:1 to obtain a solution;
The solution is spin-coated on a silicon wafer, heated, cooled, and the semi-solidified PDMS flexible film layer 3 on the silicon wafer is separated.
Specifically, the semi-cured PDMS flexible film layer 3 is bonded to the carbon nanotube film 2 and the PDMS flexible substrate layer 1, and heated.
Specifically, after bonding, electrodes are drawn out on both sides of the carbon nanotube film 2 in the intermediate layer.
For specific applications, reference may be made to the following procedure, as shown in fig. 1:
the first step: a silicon wafer mold 4 having a hemispherical recess structure 41 is fabricated using a photolithography technique, as shown in fig. 2 and 3.
And a second step of: polydimethylsiloxane (PDMS) and a cross-linking agent were mixed and stirred at a weight ratio of 10:1 for ten minutes, and then the solution was coated on the silicon wafer mold 4 having the hemispherical groove structure 41, and heated at 85 degrees celsius for 60 minutes.
And a third step of: the solution temperature obtained above was cooled at room temperature, and after solidification, the film was separated from the silicon wafer mold 4 to obtain a PDMS film (PDMS flexible substrate layer 1) having a hemispherical microstructure 11.
Fourth step: hydrogen chloride and hydrogen peroxide solution were mixed in 3:1, 5g of carbon nanotube powder is added to the mixed solution, and heated at 60 ℃ for 4 hours.
Fifth step: and adding the treated carbon nano tube into dimethylformamide solution, vacuumizing and leaking to finally obtain a layer of carbon nano tube film attached to the leaking film.
Sixth step: the leaky film was inserted into deionized water at 45 degrees of inclination, and a layer of 50-60nm thick carbon nanotube film 2 was separated from 200-300 μm thick carbon nanotube film.
Seventh step: the carbon nanotube film 2 floating on deionized water was taken out and air-dried with a nitrogen stream.
Eighth step: the carbon nanotube film 2 was transferred onto a PDMS film (PDMS flexible substrate layer 1) having a hemispherical microstructure 11, and heated at 200-220 degrees celsius for half an hour.
Ninth step: polydimethylsiloxane (PDMS) and a cross-linking agent were mixed and stirred for ten minutes at a weight ratio of 10:1, and spin-coated on a silicon wafer at 900-1100rpm, heated at 85 ℃ for half an hour, after which the solution temperature was left to cool at room temperature, and the semi-cured PDMS film (PDMS flexible film layer 3) on the silicon wafer was separated.
Tenth step: the semi-cured PDMS flexible film layer 3 was bonded to the carbon nanotube film 2 and the PDMS flexible substrate layer 1, and heated at a temperature of celsius for 30 minutes to perform tight bonding (as in fig. 1).
Eleventh step: electrodes are led out from two sides of the carbon nano tube film 2 in the middle layer, and the flexible pressure sensor is manufactured.
According to the flexible pressure sensor based on the hemispherical microstructure 11 and the manufacturing method thereof, the hemispherical inner structure is adopted in the flexible pressure sensor, the measuring range of the sensor is greatly improved, the sensor has higher sensitivity by combining the carbon nano tube with high conductivity, and the manufacturing method is improved, so that the flexible sensor is simpler and more feasible to manufacture, the manufacturing difficulty is reduced, the labor cost is reduced, the manufacturing efficiency is improved, and the standardized manufacturing process is realized.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, or alternatives falling within the spirit and principles of the invention.
Claims (6)
1. The manufacturing method of the flexible pressure sensor is characterized by comprising a PDMS flexible substrate layer, a carbon nanotube film and a PDMS flexible film layer, wherein the PDMS flexible substrate layer is provided with a microstructure, the microstructure is in a spherical bulge shape, one surface of the PDMS flexible substrate layer provided with the microstructure is covered with the carbon nanotube film, the carbon nanotube film is positioned between the PDMS flexible substrate layer and the PDMS flexible film layer, and the carbon nanotube film is connected with an electrode; the microstructure is hemispherical;
The manufacturing method comprises the following steps:
Preparing a PDMS flexible substrate layer with a microstructure in a spherical bulge shape;
Preparing a carbon nano tube film;
Covering the carbon nano tube film on the surface of the PDMS flexible substrate layer with the microstructure;
Preparing a PDMS flexible film layer and covering the PDMS flexible film layer on the carbon nanotube film;
Connecting an electrode to the carbon nanotube film;
wherein, the preparation of the PDMS flexible substrate layer comprises the following steps:
Manufacturing a silicon wafer mold with a hemispherical groove structure by adopting a photoetching technology;
Mixing and stirring PDMS and a cross-linking agent in a weight ratio of 10:1 to obtain a mixed solution, and then coating the mixed solution on the silicon wafer mold with the hemispherical grooves;
heating the silicon wafer mold and the mixed solution;
Cooling the silicon wafer mold and the mixed solution, and forming a PDMS flexible substrate layer after cooling and solidifying the mixed solution, and separating the PDMS flexible substrate layer from the silicon wafer mold to obtain the PDMS flexible substrate layer with a hemispherical microstructure;
Wherein, the preparation of the carbon nanotube film comprises the following steps:
Step one: mixing hydrogen chloride with hydrogen peroxide solution to obtain mixed solution, adding carbon nanotube powder into the mixed solution, and heating;
step two: adding the carbon nano tube in the first step into dimethylformamide solution, vacuumizing and leaking to finally obtain a layer of carbon nano tube film attached to the leaking film;
Step three: obliquely inserting the seepage film into deionized water, and separating a layer of carbon nanotube film from the carbon nanotube film obtained in the step two;
step four: the carbon nanotube film floating on deionized water was taken out and air-dried with a nitrogen stream.
2. The method of manufacturing a flexible pressure sensor according to claim 1, wherein in the third step, a 50-60nm thick carbon nanotube film is separated from a 200-300 μm thick carbon nanotube film.
3. The method of manufacturing a flexible pressure sensor of claim 1, wherein the surface of the PDMS flexible substrate layer having a microstructure is covered with the carbon nanotube film, comprising the steps of: the carbon nanotube film was transferred onto a PDMS flexible substrate layer having a hemispherical microstructure and heated.
4. A method of manufacturing a flexible pressure sensor as set forth in claim 1, wherein,
Wherein, the preparation of the PDMS flexible film layer comprises the following steps:
mixing and stirring PDMS and a cross-linking agent in a weight ratio of 10:1 to obtain a solution;
The solution is spin-coated on a silicon wafer, heated, cooled and separated from the semi-cured PDMS flexible film layer on the silicon wafer.
5. The method of manufacturing a flexible pressure sensor of claim 4, wherein a semi-cured PDMS flexible film layer is bonded to the carbon nanotube film and the PDMS flexible substrate layer and heated.
6. The method of manufacturing a flexible pressure sensor according to claim 5, wherein electrodes are led out on both sides of the carbon nanotube film of the intermediate layer after bonding.
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| CN111392690B (en) * | 2020-03-20 | 2023-04-07 | 北京航空航天大学杭州创新研究院 | Pressure sensing system based on thin film thermoelectric device power supply and preparation method thereof |
| CN114279602A (en) * | 2021-12-27 | 2022-04-05 | 杭州电子科技大学 | Pressure sensor based on two-dimensional metal sulfide and piezoelectric film and preparation method thereof |
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