Flexible interdigital capacitive sensor structure and preparation method thereof

Abstract

The invention provides a flexible interdigital capacitive sensor structure and a preparation method thereof. The sensor is composed of a substrate layer, a middle interdigital electrode layer and an upper packaging layer; the silicone rubber of the substrate layer and the silicone rubber of the upper packaging layer are formed by uniformly mixing a liquid prepolymer and a curing agent; conductive rubber used for printing the interdigital electrode is formed by uniformly mixing liquid silicone rubber, rigid conductive fiber particles, a diluent and a synergist. The preparation of the sensor comprises the steps that: preparing a substrate film, preparing an interdigital electrode; preparing an upper packaging layer; implanting an electrode; and optimizing the thicknesses of the substrate layer and the upper packaging layer of the sensor and various parameters of the interdigital electrode. In addition, the sensor has a relatively large strain working range, and has the characteristics of high sensitivity, long service life, sensing stability at different stretching speeds and real-time detection capability and characteristics of consistency of sensing detection of human body motion.

Description

technical field [0001] The invention discloses a method for preparing a flexible interdigital capacitive sensor, belonging to the field of flexible electronic equipment. Background technique [0002] In the past ten years, flexible sensors have been intensively studied and widely used in artificial intelligence, medical health, and electronic skin. Compared with piezoresistive, piezoelectric and field-effect transistor sensors, capacitive sensors are favored by researchers because of their simple structure, good temperature stability, fast dynamic response and high sensitivity. [0003] Conventional parallel-plate capacitive flexible sensors have a triple-sandwich structure, including top and bottom electrode layers and an insulating dielectric layer in the middle. The methods to improve sensitivity are mostly to build microstructures and porous structures. Since this type of sensor requires a certain microstructure to maintain the sensitivity of the sensor, it is difficult...

AI Technical Summary

Problems solved by technology

[0016] (1) The response of the current flexible interdigital sensors comes from the electrical signal changes caused by the change of the dielectric layer spacing between the interdigital electrodes, and the response sensitivity is small

[0017](2) In most patents, the preparation time of flexible interdigital sensors is relatively long, which is not suitable for mass production, and there are many kinds of materials used in the preparation of sensors and electrodes

[0018](3) The materials or solvents used in the preparation of flexible interdigital sensors in many patents have certain toxicity, which will cause certain damage to the health of the prepared experimenters and users. also pollute the environment

[0019](4) Most of the flexible interdigital sensors are pressure-sensitive sensors, temperature-sensitive sensors and curvature detection sensors, etc., which lack the preparation and performance research

[0020](5) Most of the methods for preparing flexible interdigital sensors are complex and require multi-step preparation of electrodes or resistance channels

[0021] (6) Many methods of preparing flexible interdigital sensors use metal interdigital electrodes, metal strip leads or conductive fabrics, which are not really flexible materials, resulting in their Sensor flexibility is limited

[0022](7) There is no optimization of sensor parameters and application-specific parameters to characterize the performance of the sensor

Images