| Flexible electronics-based sensory integrated systems can be used for electronic skin,wearable devices,medical devices and other fields,which is currently one of the hot research topics at domestic and international level.Flexible sensory integrated systems usually consist of two parts:flexible sensors and extendable circuits,in which flexible pressure sensors are of great interest to researchers due to their reliable performance and simple process.In order to improve the sensitivity of flexible pressure sensors,researchers have introduced microstructures of different shapes,such as spherical structures and pyramidal structures.On the other hand,researchers have also successfully fabricated flexible circuits that can be bent and stretched by using flexible micro and nano processing techniques.However,the integration of flexible sensors with flexible circuits for more comprehensive sensing and control still faces many challenges,especially in the field of array pressure detection.Accordingly,this thesis has developed a fully flexible integrated array pressure monitoring electronic system with the following main work and innovations:（1）To address the issue of pressure sensors being unable to simultaneously obtain a wide measurement range and high sensitivity,a dual-structure consisting of a cone and a cylinder was introduced,and a resistance-based flexible pressure sensor based on multi-walled carbon nanotubes（MWCNTs）was successfully developed,which can be used as the sensing part of the fully flexible electronic system designed in this thesis.It has a fast response time（response/recovery time of0.11/0.08 s）,a wide dynamic range of 6-50 k Pa,and excellent sensitivity(sensitivity is 1.61 k Pa-1for pressure below 18 k Pa,and 0.47 k Pa-1 for pressure in the range of 18-50 k Pa).（2）To deal the issue of a large number of lead-out wires in traditional array electrodes,a row-column semi-separation structure was proposed,greatly reducing the number of lead-out wires.For example,in a 4×4 array electrode,the lead-out wires will be reduced by 37.5%,making it more convenient and reliable to integrate with flexible circuits.Furthermore,In order to realize the flexibility of the array electrode,a 4×4 flexible array electrode with silver paste as conductive material on Polydimethylsiloxane（PDMS）flexible substrate was fabricated by 3D microelectronic printing technology,which could be used as an interconnected part of the fully flexible electronic system.（3）To solve the common problem of signal crosstalk in sensor arrays,an innovative conditioning circuit was proposed to solve the signal crosstalk and rapid detection of sensor arrays.By using row-column equipotential method,the circuit cut off the loop of interference current between the arrays,thus avoiding signal interference.This rapid detection method improves the detection speed of pressure signals in sensor arrays.（4）Finally,based on the magnetron sputtering and transfer process,the extendable circuit was fabricated on the PDMS flexible substrate,and the integrated process of the array flexible pressure sensor and the stretchable circuit was designed to realize the development of a fully flexible integrated electronic system integrating multiple functions such as pressure signal acquisition,processing and wireless transmission.Fully flexible means that the flexibility of the sensor,the array electrodes and the conditioning circuit is achieved.The experimental application i n the field of array pressure detection shows that the system has excellent flexibility（bending degree up to180°）and can detect 16 pressure signals in the range of 50 k Pa in real time,which shows good potential for application in the field of array pressure detection. |
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