High sensitivity square ring channel shaped MOSFET embedded pressure sensor integrated with a current mirror readout circuitry

This paper presents the design and simulation of a current mirror sensing based ring channel shaped MOSFET embedded pressure sensor. The pressure sensor is composed of two identical square ring shaped n-channel MOS transistors connected in current mirror configuration with its output transistor integrated on a silicon diaphragm. The diaphragm deflection results in the variation of drain current of embedded MOSFET due to altered channel mobility. Piezoresistive effect in MOSFET has been exploited for the calculation of strain induced carrier mobility variation under applied pressure. COMSOL Multiphysics and T-Spice are used to simulate the structural and electrical behaviour of the pressure sensor. Simulation results show that the pressure sensor has a sensitivity of approximately 407 mV/MPa in the pressure range of 0-1 MPa.