Beam-membrane MEMS capacitive pressure sensor characterized with segmented comb and lever amplification mechanism

To enhance sensitivity and reduce manufacturing complexity, we propose a MEMS capacitive pressure sensor with a beam-membrane structure featuring a 24-segment parallel comb electrode and a lever amplification mechanism. The sensor employs a 24-segment short parallel comb structure to decrease manufacturing difficulty while ensuring a substantial initial capacitance, thereby improving the sensor's reliability and cost-effectiveness. By incorporating a cantilever beam and anchor points on the upper surface of the membrane to form a lever amplification structure, the vertical displacement of the moving comb teeth is significantly increased, thus enhancing the sensor's sensitivity. Adding a central platform beneath the sensitive membrane enhances its stiffness, effectively reducing sensor nonlinearity. Experimental validation confirms that within a pressure range of 0-100 kPa, the sensitivity is 0.106 pF/kPa, with nonlinearity at 0.39 % F.S., a repeatability error of around 0.5 % F.S., and a stability error of 0.23 % F.S. The sensor, achieving high sensitivity and low nonlinearity, offers a valuable reference for the development of MEMS pressure sensors.