Investigation based on NEMS double Si3N4 resonant beams pressure sensor

A type of NEMS double Si3N4 resonant beams pressure sensor is presented in this paper. The maths models are established in allusion to the Si3N4 resonant beams and pressure sensitive diaphragm. Based on the maths model of Si3N4 resonant beams, the relation between the resonant frequency and key dimensions of Si3N4 resonant beams is analyzed. Based on the maths model of pressure sensitive diaphragm, the distribution state of stress is analyzed theoretically, through the analysis result, the position where the Si3N4 resonant beams are placed above the pressure sensitive diaphragm is optimized. The capability of the sensor which has been optimized is generally analyzed by ANSYS software of finite element analysis, a range of measured pressure is 0∼400Kpa, the coefficient of linearity correlation is 0.99346, and the sensitivity is 498.24Hz/Kpa, it is higher than silicon beam sensor's.