阅读说明：本技术 尺度可控的微皱纹金薄膜柔性裂纹传感器 (Micro-wrinkle gold thin film flexible crack sensor with controllable scale ) 是由 邹强 郑佳 于 2019-04-01 设计创作，主要内容包括：本发明公开了尺度可控的微皱纹金薄膜柔性裂纹传感器,其特征在于,包括柔性基底(1),所述柔性基底(1)的表面涂覆有氧化石墨烯层(2)；涂覆有氧化石墨烯层(2)的柔性基底(1)的表面,通过离子溅射的方式,沉积形成有金膜(3)。本发明公开的尺度可控的微皱纹金薄膜柔性裂纹传感器,其具有良好的灵敏度,能够灵敏、可靠地将所受到的外力作用情况,对应转换为电阻的变化情况,具有重大的生产实践意义。(The invention discloses a scale-controllable micro-wrinkle gold thin film flexible crack sensor which is characterized by comprising a flexible substrate (1), wherein the surface of the flexible substrate (1) is coated with a graphene oxide layer (2); the surface of the flexible substrate (1) coated with the graphene oxide layer (2) is deposited with a gold film (3) by means of ion sputtering. The scale-controllable micro-wrinkle gold film flexible crack sensor disclosed by the invention has good sensitivity, can sensitively and reliably convert the action condition of an external force into the change condition of resistance correspondingly, and has great production practice significance.)

1. The flexible crack sensor of the micro-corrugated gold film with controllable scale is characterized by comprising a flexible substrate (1), wherein the surface of the flexible substrate (1) is coated with a graphene oxide layer (2);

the surface of the flexible substrate (1) coated with the graphene oxide layer (2) is deposited with a gold film (3) by means of ion sputtering.

2. The scale-controllable micro-corrugated gold thin film flexible crack sensor according to claim 1, wherein the preparation of the flexible substrate (1) comprises the steps of:

the first step is as follows: mixing polydimethylsiloxane PDMS (polydimethylsiloxane) serving as a main agent with a curing agent according to a mass ratio of 10:1, stirring, degassing, and then, coating the mixture on a glass substrate in a suspension manner and curing;

the second step is that: peeling the cured polydimethylsiloxane PDMS from the glass substrate, pre-stretching the PDMS for a preset length to form wrinkles on the surface of the polydimethylsiloxane PDMS, then carrying out ultraviolet ozone treatment, and forming a silicon oxide SiOx layer on the outer surface of the polydimethylsiloxane PDMS, wherein x is less than or equal to 2.

3. The scale-controllable micro-corrugated gold film flexible crack sensor according to claim 2, wherein in the second step, the scale of the wrinkles formed on the surface of the PDMS is adjusted by adjusting the pre-stretched preset length.

4. The dimensionally controlled, micro-corrugated gold film flexible crack sensor according to claim 2, wherein the predetermined length is equal to twice the original length of the cured polydimethylsiloxane PDMS.

5. The dimensionally controlled, micro-corrugated gold film flexible crack sensor according to claim 2, wherein the curing agent is a hydrogen-containing silicone oil.

6. The scale-controllable micro-corrugated gold film flexible crack sensor according to claim 1, characterized in that the graphene oxide layer (2) is coated on the surface of the flexible substrate (1) by means of blade coating.

Technical Field

The invention relates to the technical field of sensors, in particular to a scale-controllable micro-wrinkle gold thin film flexible crack sensor.

Background

In recent years, strain sensors have attracted more and more interest because of the tremendous demands made on wearable electronics, artificial intelligence, intelligent health monitoring systems, and the like.

However, although flexible sensors have been developed rapidly, resistance strain sensors have had a problem that their sensitivity is often insufficient due to their limited improvement in sensitivity, and the applied external force cannot be sensitively and reliably converted into a change in resistance.

Disclosure of Invention

In view of the above, the present invention provides a scale-controllable micro-corrugated gold thin film flexible crack sensor, which has good sensitivity, can sensitively and reliably convert the external force action condition into the resistance change condition, and has great production practice significance.

To this end, the invention provides a scale-controllable micro-corrugated gold thin film flexible crack sensor, which comprises a flexible substrate, wherein the surface of the flexible substrate is coated with a graphene oxide layer;

the surface of the flexible substrate coated with the graphene oxide layer is deposited with a gold film by means of ion sputtering.

Wherein the preparation of the flexible substrate comprises the following steps:

the first step is as follows: mixing polydimethylsiloxane PDMS (polydimethylsiloxane) serving as a main agent with a curing agent according to a mass ratio of 10:1, stirring, degassing, and then, coating the mixture on a glass substrate in a suspension manner and curing;

the second step is that: peeling the cured polydimethylsiloxane PDMS from the glass substrate, pre-stretching the PDMS for a preset length to form wrinkles on the surface of the polydimethylsiloxane PDMS, then carrying out ultraviolet ozone treatment, and forming a silicon oxide SiOx layer on the outer surface of the polydimethylsiloxane PDMS, wherein x is less than or equal to 2.

In the second step, the dimension of the wrinkle formed on the surface of the polydimethylsiloxane PDMS is correspondingly adjusted by adjusting the pre-stretched preset length.

Wherein the preset length is equal to twice of the original length of the cured polydimethylsiloxane PDMS.

Wherein, the curing agent is hydrogen-containing silicone oil.

And the graphene oxide layer is coated on the surface of the flexible substrate in a blade coating mode.

Compared with the prior art, the micro-wrinkle gold film flexible crack sensor with the controllable scale has good sensitivity, can sensitively and reliably convert the action condition of the external force into the change condition of the resistance correspondingly, and has great production practice significance.

Drawings

FIG. 1 is a schematic diagram of a cross-sectional structural change of a micro-corrugated gold thin film flexible crack sensor with controllable scale provided by the invention in a preparation process;

FIG. 2 is a schematic diagram of the structural change of a micro-corrugated gold thin film flexible crack sensor with controllable scale in the manufacturing process provided by the invention;

FIG. 3 is a schematic diagram of a scale-controllable micro-corrugated gold thin film flexible crack sensor provided by the present invention in a state before stretching;

FIG. 4 is a schematic diagram of a micro-corrugated gold thin film flexible crack sensor with controllable dimensions provided by the present invention in a state after stretching;

in the figure, 1 is a flexible substrate; 2 is a graphene oxide layer; 3 is gold film and 4 is crack.

Detailed Description

In order that those skilled in the art will better understand the technical solution of the present invention, the following detailed description of the present invention is provided in conjunction with the accompanying drawings and embodiments.

Referring to fig. 1 to 4, the invention provides a scale-controllable micro-corrugated gold thin film flexible crack sensor, which includes a flexible substrate 1, wherein the surface (which may include all surfaces such as an upper surface and a lower surface, and may also be a simple upper surface) of the flexible substrate 1 is coated with a graphene oxide layer 2;

the surface of the flexible substrate 1 coated with the graphene oxide layer 2 is deposited with a gold film 3 by means of ion sputtering.

In the present invention, in a specific implementation, the preparation of the flexible substrate 1 includes the following steps:

the first step is as follows: mixing Polydimethylsiloxane (PDMS) serving as a main agent with a curing agent according to a mass ratio of 10:1, stirring and degassing, and then, coating the mixture on a glass substrate in a suspension manner and curing;

the second step is that: peeling the cured polydimethylsiloxane PDMS from the glass substrate, pre-stretching the PDMS for a preset length to form wrinkles on the surface of the polydimethylsiloxane PDMS, and then carrying out ultraviolet ozone treatment to form a silicon oxide SiOx layer (wherein x is less than or equal to 2) on the outer surface of the polydimethylsiloxane PDMS.

In a concrete implementation, the curing agent is specifically hydrogen-containing silicone oil.

In particular, the gold film 3 is a gold film deposited by an ion sputtering apparatus, and a specific substance is gold (Au).

It should be noted that, in order to obtain the resistance change condition of the flexible crack sensor, in a specific implementation of the present invention, the flexible crack sensor may be directly attached to an object to be detected, then the dupont lines (i.e., serving as connection lines) are respectively connected to two sides of the flexible crack sensor, and then the universal meter or the LCR meter is directly connected to the dupont lines (i.e., serving as connection lines), so as to measure the resistance change condition of the flexible crack sensor.

In the second step, the dimension of the wrinkle formed on the surface of the polydimethylsiloxane PDMS is correspondingly adjusted by adjusting the pre-stretched preset length, so that the controllability of the dimension of the wrinkle is realized, and the sensitivity of the flexible crack sensor is correspondingly adjusted. It should be noted that the longer the pre-stretched preset length is, the larger the dimension of the fold is, the higher the sensitivity of the flexible crack sensor of the invention is, whereas the shorter the pre-stretched preset length is, the smaller the dimension of the fold is, the lower the sensitivity of the flexible crack sensor of the invention is.

In particular, the preset length can be set according to the needs of the user, and is preferably equal to twice the original length of the cured polydimethylsiloxane PDMS.

It should be noted that the flexible substrate is made of Polydimethylsiloxane (PDMS), and a specific model of the PDMS may be dow corning 184, and the PDMS has the characteristics that: no toxicity, inertia, acid and alkali resistance, low Young's modulus, high elasticity, low Young's modulus and high stretching capacity.

It should be noted that after the flexible substrate 1 is treated by ultraviolet ozone, a SiOx layer is formed on the surface, and after the pre-stretching is released, wrinkles can be formed on the surface.

In the present invention, specifically, the graphene oxide layer 2 is coated on the surface of the flexible substrate 1 by a blade coating method.

Note that Graphene Oxide (GO) can be used to generate wrinkles with smaller dimensions by blade coating, and serves as a connection layer between the flexible substrate 1 and the gold film 3. The stretched flexible substrate 1 was spread with graphene oxide and released to form wrinkles.

In the present invention, the gold film 3 is formed by ion sputtering. A gold film was deposited on a knife-coated graphene oxide flexible substrate 1. Therefore, if the flexible substrate 1 is further stretched, the gold film 3 thereon is broken, and the resistance increases; when the stretching is released, the gold film is reconnected and the resistance is restored.

The invention is designed by fully considering the outstanding sensitivity of the self-supporting brittle conductive material during stretching, which is caused by the drastic change of resistance caused by stretching fracture, so that the brittle metal is deposited on the flexible substrate to manufacture the high-sensitivity crack sensor which can be applied to the detection of human respiration, pulse and the like.

In order that the present invention may be more clearly understood, the following description is made of the operational principle of the present invention.

For the flexible crack sensor of the invention, the scale controllable micro-wrinkle gold thin film, firstly, the known resistance value change principle needs to be explained: ohm's law of

Rho is the resistivity of the material, L is the length of the material, and s is the cross-sectional area of the material.

In the present invention, L is specifically the sensor length and s is specifically the area of gold connection at the crack. With the present invention, when the flexible substrate 1 is stretched, as can be seen from fig. 3 and 4, the sensor becomes longer, L increases, cracks 4 occur, s decreases, and therefore the resistance R increases, while the microstructure changes to exacerbate the change in s, so that the resistance R changes more rapidly, thereby increasing the sensitivity of the sensor.

For the present invention, the principle of wrinkle generation is as follows: PDMS is the flexible substrate, and the oxidation graphite alkene layer GO and the oxidation silicon SiOx on the flexible substrate surface are hard material, and after the flexible substrate is prestretched, ultraviolet ozone treatment produced SiOx on the flexible substrate surface, then the one deck GO that suspends, at this moment, tensile release, because hard material surface area reduces, form the fold.

For the present invention, in particular practice, the application examples may be: the scale-controllable micro-wrinkle gold film flexible crack sensor provided by the invention is applied to pulse detection, and can also be applied to wrist pulse, and when the sensor is stretched during pulse vibration, cracks are generated, and the resistance R is increased.

Compared with the prior art, the invention has the following beneficial technical effects due to the adoption of the technical scheme:

1. the crack sensor has high sensitivity, and only the pulsation of human pulse can be clearly sensed.

2. The fitting is tight, the flexible crack sensor with the controllable scale and the micro-wrinkle gold film is adopted to detect the activity of the human body, and the flexible substrate made of PDMS material can be tightly fitted with the human body for detection.

Compared with the prior art, the scale-controllable micro-wrinkle gold thin film flexible crack sensor has good sensitivity, can sensitively and reliably convert the action condition of the external force into the change condition of the resistance correspondingly, and has great production practice significance.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.