CN110849508A - Flexible pressure sensor based on discrete contact structure and preparation method thereof - Google Patents
Flexible pressure sensor based on discrete contact structure and preparation method thereof Download PDFInfo
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- CN110849508A CN110849508A CN201911197326.7A CN201911197326A CN110849508A CN 110849508 A CN110849508 A CN 110849508A CN 201911197326 A CN201911197326 A CN 201911197326A CN 110849508 A CN110849508 A CN 110849508A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
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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
- B81B3/0021—Transducers for transforming electrical into mechanical energy or vice versa
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/02—Electroplating of selected surface areas
- C25D5/022—Electroplating of selected surface areas using masking means
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/34—Pretreatment of metallic surfaces to be electroplated
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D7/00—Electroplating characterised by the article coated
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/20—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress
- G01L1/205—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress using distributed sensing elements
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
- G01L9/02—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in ohmic resistance, e.g. of potentiometers, electric circuits therefor, e.g. bridges, amplifiers or signal conditioning
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- 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
Abstract
The invention discloses a flexible pressure sensor based on a discrete contact structure and a preparation method thereof, wherein the method comprises the following steps: a flexible substrate; a lower electrode disposed over the flexible substrate; a contact array formed over and in electrical contact with a lower electrode; a support sidewall and an extension electrode layer, the support sidewall being disposed around the lower electrode and electrically isolated from the lower electrode; and the suspended mesh electrode is formed on the supporting side wall and is led out through the extension electrode, and the suspended mesh electrode and the contact array are separated by a certain distance under the condition of not receiving external acting force. The conductive filler nano graphite particles can be uniformly dispersed in the PI, and the formed composite material has good conductive performance and mechanical performance. The invention has the characteristics of simple preparation process, sensitive reaction, wide range and low cost.
Description
Technical Field
The invention relates to the technical field of microsensors and MEMS. In particular, the invention relates to a flexible pressure sensor based on a discrete contact structure and a preparation method thereof.
Background
With the development of human beings and the advanced development of science and technology, the requirements of people on life quality are higher and higher, so that the research and development of intelligent products such as intelligent wearable equipment, robots, unmanned planes and automatic driving which are convenient for people to work and live are greatly promoted, and the development of the products cannot be separated from pressure sensors.
The basic principles of pressure sensors are mainly resistance strain type, piezoelectric type, capacitance type, inductance type and piezoresistive type.
For a resistance strain gauge sensor, a dynamic pressure to be measured is applied to an elastic sensitive element to deform the elastic sensitive element, and a resistance strain gauge attached to a deformed portion of the elastic sensitive element senses a change in the dynamic pressure. The resistance strain gauge type sensor mainly comprises a diaphragm type sensor and a strain cylinder type sensor. Diaphragm strain gauge pressure sensors are not suitable for measuring large pressures. When the deformation is large, the linearity is poor. In the low-pressure high-frequency measurement, if the impact pressure frequency is close to the membrane self-pause frequency, the waveform and the pressure value will be distorted and lower. Strain-cylinder strain sensors are not suitable for measuring low pressures.
The piezoelectric pressure sensor converts pressure into corresponding electric signals by using the piezoelectric effect of piezoelectric materials (such as zinc oxide semiconductor materials, piezoelectric ceramics and the like), and measures pressure parameters through an amplifier, a recorder and the like. The sensor has high natural vibration frequency and can adapt to severe environment, but has poor low-frequency performance, high temperature sensitivity and harsh use and maintenance.
The inductive pressure sensor converts the pressure variation into corresponding inductance variation, and then inputs the inductance variation to an amplifier and a recorder. There are mainly air gap type and differential transformer type. Although the precision is high, but only can detect the metal original paper, application range is little, and area is big, and the power consumption is great.
A capacitive pressure sensor is a conversion device which converts a physical quantity or a mechanical quantity to be measured into capacitance change by using a capacitance sensitive element. The parallel plate type and the cylindrical type are commonly used. Has the disadvantages of high output impedance, poor load capacity and large influence of parasitic capacitance.
The piezoresistive pressure sensor is a sensor whose resistance changes when a force is applied. In the prior art, silicon wafers can be used as the elastic sensitive elements. The sensor is greatly influenced by temperature, has complex process and small measuring range. In recent years, the composite material is widely researched as a sensitive element, can be used for manufacturing flexible electronic skin, but has large hysteresis and poor stability.
Disclosure of Invention
In view of the above problems in the prior art, according to an aspect of the present invention, there is provided a multi-contact flexible pressure sensor, including:
a flexible substrate;
a lower electrode disposed over the flexible substrate;
a contact array formed over and in electrical contact with a lower electrode;
a support sidewall and an extension electrode layer, the support sidewall being disposed around the lower electrode and electrically isolated from the lower electrode; and
and the suspended mesh electrode is formed on the supporting side wall and is led out through the extension electrode, and the suspended mesh electrode and the contact array are separated by a certain distance under the condition of not receiving external acting force.
In one embodiment of the invention, under certain pressure, the suspended mesh electrode deforms to contact with a plurality of contacts in the contact array, and when the pressure is released, the suspended mesh electrode returns to the original shape.
In one embodiment of the invention, the multi-contact flexible pressure sensor further comprises an insulating layer disposed over the lower electrode and surrounding at least a portion of the side of the contact array, the contact array having a thickness greater than a thickness of the insulating layer.
In one embodiment of the invention, the contact array includes a polymer matrix and conductive particles dispersed in the polymer.
In one embodiment of the present invention, the polymer is polyimide and the conductive particles are nano-graphite particles.
In one embodiment of the present invention, the lower electrode, the supporting sidewall and the extending electrode layer, and the suspended mesh electrode are made of conductive metal material.
In one embodiment of the invention, the material of the flexible substrate is polyimide.
According to another aspect of the present invention, there is provided a method of manufacturing a multi-contact flexible pressure sensor, including:
forming a temporary bonding film on a carrier;
forming a flexible substrate on the temporary bonding film;
preparing a lower electrode on a flexible substrate;
forming an insulating layer on the lower electrode and patterning the insulating layer to form an array of windows in the insulating layer, through which a portion of the surface of the lower electrode is exposed;
forming a contact array, wherein the contact array is formed above the window array, and contacts in the contact array correspond to windows in the window array one by one, so that the contact array is electrically connected with the lower electrode;
preparing a support side wall and an extension electrode layer, wherein the support side wall is arranged around the lower electrode and is electrically isolated from the lower electrode;
preparing a suspended mesh electrode, wherein the suspended mesh electrode is formed on the supporting side wall and is led out through an extension electrode, and the suspended mesh electrode is separated from the contact array by a certain distance under the condition of not receiving external acting force; and
the multi-contact flexible pressure sensor is peeled from the slide by temporarily bonding the film.
In another embodiment of the present invention, the contact array includes a polyimide matrix and graphite nanoparticles dispersed in the polyimide, forming the contact array includes:
spin-coating a graphite nanoparticle/polyimide composite material with a certain thickness, and semi-curing at the temperature of 110 ℃ for 20 minutes;
spin-coating a photoresist, performing photoetching patterning, performing overproduction, removing the photoresist and the polyimide, and leaving the graphite nanoparticle/polyimide composite material in the contact array region;
and removing the redundant photoresist, and fully curing at the temperature of 300 ℃ for 1 hour to form the contact array.
In another embodiment of the present invention, a method for preparing a graphite nanoparticle/polyimide composite material includes: mixing graphite nano particles and polyimide according to a mass ratio of (3-5) to (97-95), then carrying out ball milling for 10-24 hours, then carrying out ultrasonic mixing for 1 hour, uniformly mixing, and carrying out vacuum degassing to form the graphite nano particle/polyimide composite material.
The pressure sensor is prepared by repeating the processes of sputtering, photoetching and patterning, electroplating and the like for many times, the preparation process is simple, the cost is lower, and the method can be used for industrial production. The invention has simple principle through the design of suspended net shape and a plurality of tiny metal contacts, thus leading the data processing to be not complicated and being more beneficial to the array of the device. The invention can sense a large pressure range by adjusting the structural parameters, thereby expanding the application range of the pressure sensing device.
Drawings
To further clarify the above and other advantages and features of embodiments of the present invention, a more particular description of embodiments of the invention will be rendered by reference to the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. In the drawings, the same or corresponding parts will be denoted by the same or similar reference numerals for clarity.
FIG. 1 illustrates a perspective view of a multi-contact flexible pressure sensor in accordance with one embodiment of the present invention.
FIG. 2 illustrates a top view of a multi-contact flexible pressure sensor, according to one embodiment of the present invention.
FIG. 3 illustrates a front view of a multi-contact flexible pressure sensor, according to one embodiment of the present invention.
Fig. 4A-4E illustrate a schematic diagram of a manufacturing process for a multi-contact flexible pressure sensor, according to one embodiment of the invention.
FIG. 5 illustrates a flow diagram of a method of fabricating a multi-contact flexible pressure sensor according to one embodiment of the present invention.
FIG. 6 illustrates a perspective view of a multi-contact flexible pressure sensor, according to one embodiment of the present invention.
FIG. 7 illustrates a top view of a multi-contact flexible pressure sensor, in accordance with one embodiment of the present invention.
FIG. 8 illustrates a front view of a multi-contact flexible pressure sensor, according to one embodiment of the present invention.
FIG. 9 illustrates a test circuit diagram for a multi-contact flexible pressure sensor in accordance with one embodiment of the present invention.
Fig. 10A-10E illustrate a schematic diagram of a manufacturing process for a multi-contact flexible pressure sensor, according to one embodiment of the invention.
Detailed Description
In the following description, the invention is described with reference to various embodiments. One skilled in the relevant art will recognize, however, that the embodiments may be practiced without one or more of the specific details, or with other alternative and/or additional methods, materials, or components. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of embodiments of the invention. Similarly, for purposes of explanation, specific numbers, materials and configurations are set forth in order to provide a thorough understanding of the embodiments of the invention. However, the invention may be practiced without specific details. Further, it should be understood that the embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale.
Reference in the specification to "one embodiment" or "the embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment.
The embodiment of the invention provides a polymer-based multi-contact flexible pressure sensor and a preparation method thereof. The suspended mesh electrode is contacted with the contact by applying pressure, the number of the contact points contacted with the suspended mesh electrode is increased when the applied pressure is increased, then the resistance or current change between the upper electrode and the lower electrode under different pressures is tested, and the magnitude of the applied pressure is represented by the magnitude of the resistance or current. The MEMS processing technology is simple in process, low in manufacturing cost, small in device size and simple in test, and the application range of the MEMS processing technology is greatly improved.
FIG. 1 illustrates a perspective view of a multi-contact flexible pressure sensor in accordance with one embodiment of the present invention. FIG. 2 illustrates a top view of a multi-contact flexible pressure sensor, according to one embodiment of the present invention. FIG. 3 illustrates a front view of a multi-contact flexible pressure sensor, according to one embodiment of the present invention.
Referring to fig. 1 to 3, the multi-contact flexible pressure sensor includes: the device comprises a flexible substrate 1, a lower electrode 2, a contact array 4, a supporting side wall and extending electrode layer 5 and a suspended mesh electrode 6.
In one embodiment of the present invention, the flexible substrate 1 may be prepared by spin coating high viscosity Polyimide (PI) on a glass substrate.
In one embodiment of the present invention, the lower electrode 2, the supporting sidewall and extension electrode layer 5 and the suspended mesh electrode 6 may be made of a conductive metal material. For example, the lower electrode 2, the supporting sidewall and extension electrode layer 5, and the suspended mesh electrode 6 may be formed by plating a conductive metal having excellent conductivity and a certain mechanical strength. The metal may be selected from one or more of copper (Cu), nickel (Ni), gold (Au), or the like. The lower electrode 2, the supporting sidewall and extension electrode layer 5, and the suspended mesh electrode 6 may be formed of a stack of multiple layers of metal or an alloy of multiple metals. The suspended mesh electrode 6 is required to have certain toughness and rigidity, so that the suspended mesh electrode can deform to contact with the contact under the action of certain pressure, and the suspended mesh electrode 6 can restore to the original shape when the pressure is relieved. The suspended mesh electrode 6 has simple processing technology and low cost.
The suspended mesh electrode 6 and the contact array 4 form a discrete contact structure, wherein the discrete contact structure is a contact process which discretizes a contact process generated by pressure and discretizes a continuous contact process into a plurality of contacts. The invention adopts a distributed contact array to sense external pressure, the number of contact points represents the magnitude of the pressure, and the two-dimensional distribution of the contact points represents the direction of the pressure.
In one embodiment of the present invention, the contact array 4 may be a contact array formed by uniformly dispersing conductive particles in a patternable resin and then patterning. The patternable resin includes, for example, polyimide, photosensitive epoxy resin, solder resist ink, green paint, dry film, photosensitive build-up material, BCB (bis-benzocyclobutene resin), or PBO (phenyl benzobisoxazole resin). In embodiments of the present invention, the patternable resin is preferably polyimide. The conductive particles may be metallic conductive particles, such as gold nanoparticles, copper nanoparticles, and the like. The conductive particles are preferably nano graphite particles, because the nano graphite particles can improve the pressure resistance and the conductivity of the polyimide, and the nano graphite particles have good adhesion and can be uniformly dispersed in the polyimide.
In other embodiments of the present invention, the contact array may also be a conductive array formed of other materials, such as an array of metal bumps, which may be formed by photolithography and electroplating.
In one embodiment of the invention, an insulating layer 3 may also be provided around the contact array 4. The insulating layer 3 fills the gaps between the contact arrays 4. The insulating layer 3 may be made of patterned polyimide. However, the scope of the present invention is not limited thereto, and in other embodiments of the present invention, the insulating layer 3 may be made of other insulating materials, for example, silicon dioxide, alumina, SU8 glue, polymethylmethacrylate PMMA, parylene-C, and the like.
The substrate of the contact array 4 and the insulating layer 3 are preferably PI as a polymer because of its excellent overall performance and compatibility with a microfabrication process, capability of patterning, etc.
The lower electrode 2 is disposed on the flexible substrate 1, and the lower electrode 2 has a specific shape and area. The shape and area of the lower electrode 2 can be set by those skilled in the art according to actual needs. An insulating layer 3 and a contact array 4 are formed over the lower electrode 2. The contact array 4 is in electrical contact with the lower electrode 2. The support sidewall surrounds the lower electrode 2 and is electrically isolated from the lower electrode 2. A suspended mesh electrode 6 is formed on the supporting sidewall. The suspended mesh electrode 6 is spaced a specific distance from the contact array 4 in the absence of an external force. The suspended mesh electrode 6 is led out through the extended electrode 5.
In the embodiment shown in fig. 1-3, the suspended mesh electrode 6 is in the shape of a metal mesh with contact pads on the corresponding areas above the contacts. However, it should be clear to those skilled in the art that the shape of the suspended mesh electrode 6 is not limited thereto, and the suspended mesh electrode 6 may have other mesh shapes. The invention is not limited to a particular grid pattern.
For the multi-contact flexible pressure sensor disclosed by the invention, when certain pressure is applied to the suspended metal mesh electrode layer, on one hand, the suspended mesh electrode is contacted with the contact to form a conductive path, and on the other hand, the suspended mesh electrode cannot be directly contacted with the lower electrode due to the existence of the insulating layer. Therefore, the suspended mesh electrode, the contact array and the lower electrode form a pressure sensor, and the magnitude of the applied external force can be determined by measuring the magnitude of the resistance or the current.
Fig. 4A-4E illustrate a schematic diagram of a manufacturing process for a multi-contact flexible pressure sensor, according to one embodiment of the invention. FIG. 5 illustrates a flow diagram of a method of fabricating a multi-contact flexible pressure sensor according to one embodiment of the present invention.
First, at step 501, a slide is provided. In the embodiment of the present invention, the carrier sheet may be a glass carrier sheet, a monocrystalline silicon wafer, an organic substrate, a metal substrate, a ceramic substrate, a substrate formed by combining an organic substrate and a metal substrate, or other similar materials. It will be understood by those skilled in the art that flat surfaces of a particular strength may be used as the carrier sheet in the present invention. The slide can be cleaned as needed prior to fabrication of the multi-contact flexible pressure sensor. The slide can be cleaned by selecting alkali, acid solution and/or deionized water according to the material of the slide, and then dried.
At step 502, a temporary bonding film is formed on a carrier sheet. The temporary bonding film may be a thermoplastic or thermosetting organic material, or an inorganic material containing Cu, Ni, Cr, Co, or the like, and may be peeled off by heating, mechanical, chemical, laser, freezing, or the like. In one embodiment of the present invention, the temporary bonding film is Polydimethylsiloxane (PDMS). Specifically, a certain thickness of Polydimethylsiloxane (PDMS) was spin-coated on a slide glass, and then baked at 180 ℃ for 1 hour, the thickness of the spin-coated PDMS was 20 to 30 micrometers.
At step 503, a flexible substrate 1 is formed on the temporary bonding film. The flexible substrate 1 can be prepared by spin-coating high-viscosity Polyimide (PI) on a carrier plate, semi-curing at 120 ℃ for 1 hour, then heating to 300 ℃ for full curing for 1 hour, and finishing the preparation of the flexible substrate. The thickness of the flexible substrate 1 is 30-60 microns.
At step 504, the lower electrode 2 is prepared on the flexible substrate 1, as shown in fig. 4A. Specifically, in one embodiment of the present invention, a Cr/Cu seed layer is sputtered on a flexible substrate, a photoresist is spin-coated, the lower electrode is patterned by photolithography, and then copper, nickel or gold is electroplated to form the lower electrode 2 with a certain thickness. It will be understood by those skilled in the art that the material of the seed layer and the lower electrode 2 is not limited to the specific metal materials indicated in the above embodiments. The thickness of the lower electrode 2 may be in the range of 1-3 microns.
In step 505, an insulating layer 3 is formed on the lower electrode 2 and patterned, as shown in fig. 2B. The insulating layer 3 may be made of patterned polyimide. Specifically, polyimide with a certain thickness is coated in a spinning mode and semi-cured for 20min at the temperature of 110 ℃; spin-coating photoresist, carrying out photoetching and patterning, carrying out overproof development, removing the photoresist and PI, then removing the redundant photoresist, and carrying out full curing for 1h at the temperature of 300 ℃ to form the insulating layer 3. However, the scope of the present invention is not limited thereto, and in other embodiments of the present invention, the insulating layer 3 may be made of other insulating materials, for example, silicon dioxide, alumina, SU8 glue, polymethylmethacrylate PMMA, parylene-C, and the like. An array of windows is formed in the insulating layer 3 by a patterning process. A part of the surface of the lower electrode 2 is exposed through the window array. The window array corresponds to a contact array to be formed later, thereby achieving electrical connection between the contact array and the lower electrode 2. The thickness of the insulating layer 3 is in the range of 0.8-1.5 microns.
At step 506, a contact array 4 is formed, as shown in FIG. 2C. Specifically, in one embodiment of the present invention, the material of the contact array 4 includes polyimide and conductive particles dispersed therein. The preparation method comprises the following steps: spin-coating a graphite/PI composite material with a certain thickness, and semi-curing at the temperature of 110 ℃ for 20 minutes; spin-coating photoresist, photoetching and patterning, over-developing, removing the photoresist and PI, leaving the graphite/PI composite material in the contact array area, then removing the redundant photoresist, and fully curing at the temperature of 300 ℃ for 1 hour to form the contact array. The graphite/PI composite has a thickness in the range of 6-8 microns. The preparation method of the graphite/PI composite material can comprise the following steps: mixing graphite nano particles and PI according to a mass ratio of (3-5) to (97-95), then carrying out ball milling for 10-24 hours, then carrying out ultrasonic mixing for 1 hour, uniformly mixing, and carrying out vacuum degassing to form the graphite/PI composite material.
In step 507, the support sidewall and extension electrode layer 5 are prepared, as shown in fig. 2D. Specifically, in one embodiment of the invention, a Cr/Cu seed layer is sputtered, a photoresist is coated in a spinning mode to serve as a sacrificial layer, photoetching patterning is carried out, and the areas where the supporting side walls and the extension electrode layer are located are exposed; then, copper, nickel or gold is electroplated to form a support sidewall and an extension electrode layer with a certain thickness. The thickness of the supporting sidewalls and the extension electrode layer 5 is in the range of 10-30 microns.
At step 508, suspended mesh electrodes 6 are prepared, as shown in FIG. 2E. Specifically, in one embodiment of the present invention, a Cr/Cu seed layer is sputtered, a photoresist is spin-coated, patterned by photolithography to expose the area where the mesh electrode is located, and then copper, nickel or gold is electroplated to form a mesh electrode layer with a certain thickness. And then, removing the redundant photoresist in the photoresist sacrificial layer by using a weak alkaline solution to form a suspended mesh electrode. The thickness of the mesh electrode layer is in the range of 10-30 microns.
At step 509, the multi-contact flexible pressure sensor is peeled from the slide by temporarily bonding the film. In an embodiment of the present invention, a suitable peeling process may be selected according to the material characteristics of the temporary bonding film used. For example, when the temporary bonding film is Polydimethylsiloxane (PDMS), the preparation of the polymer-based multi-contact flexible pressure sensor is completed by heat peeling, i.e., the slide is placed on a 70 ℃ hot plate, and the PI substrate is peeled off and separated from the PDMS.
In the above-described step, when polyimide is used for the flexible substrate 1, the insulating layer 3, and the contact array 4, the thicknesses of the flexible substrate 1, the insulating layer 3, and the contact array 4 can be determined by the spin-coating speed and the spin-coating time of the spin coater. The thicknesses of the lower electrode 2, the supporting sidewall and extension electrode layer 4 and the mesh electrode 6 may be determined by the plating rate and the plating time.
The pressure sensor is prepared by repeating the processes of sputtering, photoetching and patterning, electroplating and the like for many times, the preparation process is simple, the cost is lower, and the method can be used for industrial production. The invention has simple principle through the design of suspended net shape and a plurality of tiny metal contacts, thus leading the data processing to be not complicated and being more beneficial to the array of the device. The invention can sense a large pressure range by adjusting the structural parameters, thereby expanding the application range of the pressure sensing device.
In the embodiment of the invention, under the action of certain pressure, the suspended mesh electrode deforms to be in contact with a plurality of contacts in the contact array, each contacted contact and the suspended mesh electrode form a conductive path, and a plurality of connected contacts form a parallel conductive network. And as the pressure increases, the number of contacts that make contact increases, and more contacts form a parallel connection. The number of contact points thus increases in proportion to the current to be measured. The contact array can also be addressed by adopting an addressing circuit, and qualitative representation of the pressure direction is realized by analyzing the two-dimensional distribution of contact.
FIG. 6 illustrates a perspective view of a multi-contact flexible pressure sensor, according to one embodiment of the present invention. FIG. 7 illustrates a top view of a multi-contact flexible pressure sensor, in accordance with one embodiment of the present invention. FIG. 8 illustrates a front view of a multi-contact flexible pressure sensor, according to one embodiment of the present invention.
Referring to fig. 6 to 8, the multi-contact flexible pressure sensor includes: flexible substrate 21, lower electrode 22, contact array 24, support sidewall and extension electrode layer 25, and suspended mesh electrode 26. The multi-contact flexible pressure sensor shown in fig. 6 to 8 is similar to the multi-contact flexible pressure sensor shown in fig. 1 to 3, and detailed description of similar parts is omitted in order to simplify the description of the present invention.
The main differences from the multi-contact flexible pressure sensor shown in fig. 1 to 3 are: the lower electrode 22 is patterned as a column electrode, the support sidewalls as well as the extension electrode 25 and the suspended mesh electrode 26 are patterned as a row electrode. In the test process, only one excitation signal is applied to the row electrode at each moment, and then signal acquisition is performed at the column electrode end. Thus, the signal value of a row and column of contacts can be determined. And the qualitative representation of the pressure direction is realized by analyzing the two-dimensional distribution of contact. FIG. 9 illustrates a test circuit diagram for a multi-contact flexible pressure sensor in accordance with one embodiment of the present invention. The test circuit includes a control circuit and an analog/digital conversion circuit. In the test process, at each moment, the control circuit only applies one path of excitation signals to the row electrodes, and then signal acquisition is carried out at the column electrode ends.
Fig. 10A-10E illustrate a schematic diagram of a manufacturing process for a multi-contact flexible pressure sensor, according to one embodiment of the invention.
First, a slide is provided. In the embodiment of the present invention, the carrier sheet may be a glass carrier sheet, a monocrystalline silicon wafer, an organic substrate, a metal substrate, a ceramic substrate, a substrate formed by combining an organic substrate and a metal substrate, or other similar materials. It will be understood by those skilled in the art that flat surfaces of a particular strength may be used as the carrier sheet in the present invention. The slide can be cleaned as needed prior to fabrication of the multi-contact flexible pressure sensor. The slide can be cleaned by selecting alkali, acid solution and/or deionized water according to the material of the slide, and then dried.
A temporary bonding film is formed on the carrier sheet. The temporary bonding film may be a thermoplastic or thermosetting organic material, or an inorganic material containing Cu, Ni, Cr, Co, or the like, and may be peeled off by heating, mechanical, chemical, laser, freezing, or the like. In one embodiment of the present invention, the temporary bonding film is Polydimethylsiloxane (PDMS). Specifically, a certain thickness of Polydimethylsiloxane (PDMS) was spin-coated on a slide glass, and then baked at 180 ℃ for 1 hour, the thickness of the spin-coated PDMS was 20 to 30 micrometers.
A flexible substrate 21 is formed on the temporary bonding film. The flexible substrate 21 may be prepared by spin-coating high-viscosity Polyimide (PI) on a carrier, semi-curing at 120 ℃ for 1 hour, then heating to 300 ℃ for full curing for 1 hour, and completing the preparation of the flexible substrate. The thickness of the flexible substrate 1 is 30-60 microns.
The lower electrode 22 is prepared on the flexible substrate 21 as shown in fig. 10A. Specifically, in one embodiment of the present invention, a Cr/Cu seed layer is sputtered onto the flexible substrate, a photoresist is spin coated, the lower electrode is patterned by photolithography, and then copper, nickel or gold is electroplated to form the lower electrode 22 with a certain thickness. It should be understood by those skilled in the art that the material of the seed layer and the lower electrode 22 is not limited to the specific metal materials indicated in the above embodiments. The thickness of the lower electrode 22 may be in the range of 1-3 microns.
An insulating layer 23 is formed on the lower electrode 22 and patterned as shown in fig. 10B. The insulating layer 23 may be made of patterned polyimide. Specifically, polyimide with a certain thickness is coated in a spinning mode and semi-cured for 20min at the temperature of 110 ℃; spin-coating photoresist, carrying out photoetching patterning, developing, removing the photoresist and PI, removing the redundant photoresist, and carrying out full curing at 300 ℃ for 1h to form the insulating layer 23. However, the scope of the present invention is not limited thereto, and in other embodiments of the present invention, the insulating layer 23 may be made of other insulating materials, for example, silicon dioxide, alumina, SU8 glue, polymethylmethacrylate PMMA, parylene-C, and the like. An array of windows is formed in the insulating layer 23 by a patterning process. A portion of the surface of the lower electrode 22 is exposed through the array of windows. The array of windows corresponds to a subsequently formed array of contacts to effect an electrical connection between the array of contacts and the lower electrode 22. The thickness of the insulating layer 23 is in the range of 0.8-1.5 microns.
A contact array 24 is formed as shown in fig. 10C. Specifically, in one embodiment of the present invention, the material of the contact array 24 includes polyimide and conductive particles dispersed therein. The preparation method comprises the following steps: spin-coating a graphite/PI composite material with a certain thickness, and semi-curing at the temperature of 110 ℃ for 20 minutes; spin-coating photoresist, photoetching and patterning, over-developing, removing the photoresist and PI, leaving the graphite/PI composite material in the contact array area, then removing the redundant photoresist, and fully curing at the temperature of 300 ℃ for 1 hour to form the contact array. The graphite/PI composite has a thickness in the range of 6-8 microns. The preparation method of the graphite/PI composite material can comprise the following steps: mixing graphite nano particles and PI according to a mass ratio of (3-5) to (97-95), then carrying out ball milling for 10-24 hours, then carrying out ultrasonic mixing for 1 hour, uniformly mixing, and carrying out vacuum degassing to form the graphite/PI composite material.
Support sidewalls and extension electrode layers 25 are prepared as shown in fig. 10D. Specifically, in one embodiment of the invention, a Cr/Cu seed layer is sputtered, a photoresist is coated in a spinning mode to serve as a sacrificial layer, photoetching patterning is carried out, and the areas where the supporting side walls and the extension electrode layer are located are exposed; then, copper, nickel or gold is electroplated to form a support sidewall and an extension electrode layer with a certain thickness. The thickness of the supporting sidewalls and the extension electrode layer 25 is in the range of 10-30 microns.
A suspended mesh electrode 26 is prepared as shown in fig. 10E. Specifically, in one embodiment of the present invention, a Cr/Cu seed layer is sputtered, a photoresist is spin-coated, patterned by photolithography to expose the area where the mesh electrode is located, and then copper, nickel or gold is electroplated to form a mesh electrode layer with a certain thickness. And then, removing the redundant photoresist in the photoresist sacrificial layer by using a weak alkaline solution to form a suspended mesh electrode. The thickness of the mesh electrode layer is in the range of 10-30 microns.
The multi-contact flexible pressure sensor is peeled from the slide by temporarily bonding the film. In an embodiment of the present invention, a suitable peeling process may be selected according to the material characteristics of the temporary bonding film used. For example, when the temporary bonding film is Polydimethylsiloxane (PDMS), the preparation of the polymer-based multi-contact flexible pressure sensor is completed by heat peeling, i.e., the slide is placed on a 70 ℃ hot plate, and the PI substrate is peeled off and separated from the PDMS.
The pressure sensor is prepared by repeating the processes of sputtering, photoetching and patterning, electroplating and the like for many times, the preparation process is simple, the cost is lower, and the method can be used for industrial production. The invention has simple principle through the design of suspended net shape and a plurality of tiny metal contacts, thus leading the data processing to be not complicated and being more beneficial to the array of the device. The invention can sense a large pressure range by adjusting the structural parameters, thereby expanding the application range of the pressure sensing device.
While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to persons skilled in the relevant art that various combinations, modifications, and changes can be made thereto without departing from the spirit and scope of the invention. Thus, the breadth and scope of the present invention disclosed herein should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.
Claims (10)
1. A flexible pressure sensor comprising:
a flexible substrate;
a lower electrode disposed over the flexible substrate;
a contact array formed over and in electrical contact with a lower electrode;
a support sidewall and an extension electrode layer, the support sidewall being disposed around the lower electrode and electrically isolated from the lower electrode; and
and the suspended mesh electrode is formed on the supporting side wall and is led out through the extension electrode, and the suspended mesh electrode and the contact array are separated by a certain distance under the condition of not receiving external acting force.
2. The flexible pressure sensor of claim 1 wherein the suspended mesh electrode deforms under a certain pressure to contact the plurality of contacts in the array of contacts and returns to its original shape when the pressure is released.
3. The flexible pressure sensor of claim 1, further comprising an insulating layer disposed over the lower electrode and surrounding at least a portion of a side of the contact array, the contact array having a thickness greater than a thickness of the insulating layer.
4. The flexible pressure sensor of claim 1, wherein the contact array comprises a polymer matrix and conductive particles dispersed in the polymer.
5. The flexible pressure sensor of claim 4, wherein the polymer is polyimide and the conductive particles are nano-graphite particles.
6. The flexible pressure sensor of claim 1 wherein the lower electrode, the supporting sidewall and extension electrode layer, and the suspended mesh electrode are made of a conductive metal material.
7. The flexible pressure sensor of claim 1, wherein the material of the flexible substrate is polyimide.
8. A method of making a flexible pressure sensor, comprising:
forming a temporary bonding film on a carrier;
forming a flexible substrate on the temporary bonding film;
preparing a lower electrode on a flexible substrate;
forming an insulating layer on the lower electrode and patterning the insulating layer to form an array of windows in the insulating layer, through which a portion of the surface of the lower electrode is exposed;
forming a contact array, wherein the contact array is formed above the window array, and contacts in the contact array correspond to windows in the window array one by one, so that the contact array is electrically connected with the lower electrode;
preparing a support side wall and an extension electrode layer, wherein the support side wall is arranged around the lower electrode and is electrically isolated from the lower electrode;
preparing a suspended mesh electrode, wherein the suspended mesh electrode is formed on the supporting side wall and is led out through an extension electrode, and the suspended mesh electrode is separated from the contact array by a certain distance under the condition of not receiving external acting force; and
the multi-contact flexible pressure sensor is peeled from the slide by temporarily bonding the film.
9. The method of making a flexible pressure sensor of claim 8, wherein the contact array comprises a polyimide matrix and graphite nanoparticles dispersed in the polyimide, and forming the contact array comprises:
spin-coating a graphite nanoparticle/polyimide composite material with a certain thickness, and semi-curing at the temperature of 110 ℃ for 20 minutes;
spin-coating a photoresist, performing photoetching patterning, performing overproduction, removing the photoresist and the polyimide, and leaving the graphite nanoparticle/polyimide composite material in the contact array region;
and removing the redundant photoresist, and fully curing at the temperature of 300 ℃ for 1 hour to form the contact array.
10. The method of making a flexible pressure sensor of claim 9, wherein the graphite nanoparticle/polyimide composite material is made by a method comprising: mixing graphite nano particles and polyimide according to a mass ratio of (3-5) to (97-95), then carrying out ball milling for 10-24 hours, then carrying out ultrasonic mixing for 1 hour, uniformly mixing, and carrying out vacuum degassing to form the graphite nano particle/polyimide composite material.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112014007A (en) * | 2020-08-24 | 2020-12-01 | 北京大学 | Array type flexible pressure sensor with high mechanical strength and preparation method thereof |
| CN112432589A (en) * | 2020-11-30 | 2021-03-02 | 中南大学 | Parallel flexible strain sensor and preparation method thereof |
| CN114623958A (en) * | 2022-02-25 | 2022-06-14 | 武汉大学 | Flexible touch sensor based on electrode array and preparation method thereof |
Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1211633B1 (en) * | 2000-11-28 | 2004-06-09 | STMicroelectronics S.r.l. | Texile-like capacitive pressure sensor and method of mapping the pressure exerted at points of a surface of a flexible and pliable object, particularly of a sail |
| WO2009034677A1 (en) * | 2007-09-10 | 2009-03-19 | Newcom, Inc. | Pressure distribution detector utilizing electromagnetic coupling |
| CN101776496A (en) * | 2009-01-09 | 2010-07-14 | 财团法人工业技术研究院 | Flexible electronic pressure sensing device and manufacturing method thereof |
| US20110226069A1 (en) * | 2010-03-18 | 2011-09-22 | Korea Research Institute Of Standards And Science | Flexible force or pressure sensor array using semiconductor strain gauge, fabrication method thereof and measurement method thereof |
| CN102306583A (en) * | 2011-08-31 | 2012-01-04 | 上海交通大学 | Miniature pressure switch with three-dimensional multidirectional sensitivity property |
| CN103063340A (en) * | 2011-10-19 | 2013-04-24 | 郭松 | Two-dimensional matrix sensor of thin-film-shaped soft sensing materials |
| CN103837272A (en) * | 2012-11-27 | 2014-06-04 | Ge医疗***环球技术有限公司 | Curved-surface film pressure sensor and manufacturing method thereof |
| CN105670297A (en) * | 2016-01-28 | 2016-06-15 | 深圳市慧瑞电子材料有限公司 | Conductive rubber material for flexible sensors as well as preparation method and application of conductive rubber material |
| CN106092389A (en) * | 2016-05-27 | 2016-11-09 | 电子科技大学 | A kind of novel array-type flexible pressure transducer |
| CN106197772A (en) * | 2016-07-06 | 2016-12-07 | 无锡格菲电子薄膜科技有限公司 | A kind of pliable pressure sensor and preparation method thereof |
| CN106932128A (en) * | 2017-04-21 | 2017-07-07 | 清华大学深圳研究生院 | For the pressure sensitive layer and piezoresistive pressure sensor of piezoresistive pressure sensor |
| CN206740283U (en) * | 2017-04-21 | 2017-12-12 | 清华大学深圳研究生院 | Pressure sensitive layer, piezoresistive pressure sensor and pressure drag type pressure sensor array |
| KR20180069990A (en) * | 2016-12-15 | 2018-06-26 | 연세대학교 산학협력단 | High sensitive flexible pressure sensor and method thereof |
| CN109091120A (en) * | 2018-06-19 | 2018-12-28 | 华东师范大学 | A method of flexible sensor is made based on growth in situ silver electrode on paper |
| CN208721291U (en) * | 2018-07-20 | 2019-04-09 | 浙江大学 | A kind of flexible resistive array of pressure sensors |
| CN109724724A (en) * | 2018-12-27 | 2019-05-07 | 武汉飞帛丝科技有限公司 | Pressure distributed flexible sensor and preparation method thereof |
| CN109813467A (en) * | 2019-03-25 | 2019-05-28 | 南方科技大学 | A kind of pressure sensor and its preparation method and application |
| CN110095211A (en) * | 2019-05-24 | 2019-08-06 | 清华大学深圳研究生院 | A kind of stretchable tactile sensor array and preparation method thereof |
-
2019
- 2019-11-29 CN CN201911197326.7A patent/CN110849508B/en active Active
Patent Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1211633B1 (en) * | 2000-11-28 | 2004-06-09 | STMicroelectronics S.r.l. | Texile-like capacitive pressure sensor and method of mapping the pressure exerted at points of a surface of a flexible and pliable object, particularly of a sail |
| WO2009034677A1 (en) * | 2007-09-10 | 2009-03-19 | Newcom, Inc. | Pressure distribution detector utilizing electromagnetic coupling |
| CN101776496A (en) * | 2009-01-09 | 2010-07-14 | 财团法人工业技术研究院 | Flexible electronic pressure sensing device and manufacturing method thereof |
| US20110226069A1 (en) * | 2010-03-18 | 2011-09-22 | Korea Research Institute Of Standards And Science | Flexible force or pressure sensor array using semiconductor strain gauge, fabrication method thereof and measurement method thereof |
| CN102306583A (en) * | 2011-08-31 | 2012-01-04 | 上海交通大学 | Miniature pressure switch with three-dimensional multidirectional sensitivity property |
| CN103063340A (en) * | 2011-10-19 | 2013-04-24 | 郭松 | Two-dimensional matrix sensor of thin-film-shaped soft sensing materials |
| CN103837272A (en) * | 2012-11-27 | 2014-06-04 | Ge医疗***环球技术有限公司 | Curved-surface film pressure sensor and manufacturing method thereof |
| CN105670297A (en) * | 2016-01-28 | 2016-06-15 | 深圳市慧瑞电子材料有限公司 | Conductive rubber material for flexible sensors as well as preparation method and application of conductive rubber material |
| CN106092389A (en) * | 2016-05-27 | 2016-11-09 | 电子科技大学 | A kind of novel array-type flexible pressure transducer |
| CN106197772A (en) * | 2016-07-06 | 2016-12-07 | 无锡格菲电子薄膜科技有限公司 | A kind of pliable pressure sensor and preparation method thereof |
| KR20180069990A (en) * | 2016-12-15 | 2018-06-26 | 연세대학교 산학협력단 | High sensitive flexible pressure sensor and method thereof |
| CN106932128A (en) * | 2017-04-21 | 2017-07-07 | 清华大学深圳研究生院 | For the pressure sensitive layer and piezoresistive pressure sensor of piezoresistive pressure sensor |
| CN206740283U (en) * | 2017-04-21 | 2017-12-12 | 清华大学深圳研究生院 | Pressure sensitive layer, piezoresistive pressure sensor and pressure drag type pressure sensor array |
| CN109091120A (en) * | 2018-06-19 | 2018-12-28 | 华东师范大学 | A method of flexible sensor is made based on growth in situ silver electrode on paper |
| CN208721291U (en) * | 2018-07-20 | 2019-04-09 | 浙江大学 | A kind of flexible resistive array of pressure sensors |
| CN109724724A (en) * | 2018-12-27 | 2019-05-07 | 武汉飞帛丝科技有限公司 | Pressure distributed flexible sensor and preparation method thereof |
| CN109813467A (en) * | 2019-03-25 | 2019-05-28 | 南方科技大学 | A kind of pressure sensor and its preparation method and application |
| CN110095211A (en) * | 2019-05-24 | 2019-08-06 | 清华大学深圳研究生院 | A kind of stretchable tactile sensor array and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 熊耀旭等: "微纳结构柔性压力传感器的制备及应用", 《化学进展》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112014007A (en) * | 2020-08-24 | 2020-12-01 | 北京大学 | Array type flexible pressure sensor with high mechanical strength and preparation method thereof |
| CN112014007B (en) * | 2020-08-24 | 2022-03-25 | 北京大学 | Array type flexible pressure sensor with high mechanical strength and preparation method thereof |
| CN112432589A (en) * | 2020-11-30 | 2021-03-02 | 中南大学 | Parallel flexible strain sensor and preparation method thereof |
| CN112432589B (en) * | 2020-11-30 | 2022-06-24 | 中南大学 | Parallel flexible strain sensor and preparation method thereof |
| CN114623958A (en) * | 2022-02-25 | 2022-06-14 | 武汉大学 | Flexible touch sensor based on electrode array and preparation method thereof |
| CN114623958B (en) * | 2022-02-25 | 2023-06-20 | 武汉大学 | Flexible touch sensor based on electrode array and preparation method thereof |
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