An Innovative LC-C Resonant Pressure Sensor Based on Capacitive Feedthroughs

LC resonant wireless passive pressure sensor has been receiving increased attention nowadays. In this paper, an innovative LC-C resonant wireless passive pressure sensor based on dual capacitors was designed and manufactured to replace the traditional LC device. In addition to the inductor and capacitor structure required by the traditional LC device, this paper innovatively designs the fixed capacitor as the inter-layer interconnection structure. The key structural dimensions of the sensor were determined through the numerical analysis of the planar inductor theory and the electromechanical coupling simulation of the dual capacitors model in the previous stage, and the processing of the sensor was carried out through MEMS technology. The final test results showed that within the pressure range of 5kPa to 100kPa, the sensor’s average sensitivity was greater than 69.0 kHz/kPa, while the maximum linear fitting error was smaller than 4.18%. The temperature drift in atmospheric environment was 2.7kHz/°C, and the sensitivity temperature drift was 0.0062kHz/(kPa·°C).