A conceptual and simulation study on curved MOSFET based current mirror integrated pressure sensors (CM-CMIPS)

Abstract

A simulation study on curved MOSFET-based current mirror integrated pressure sensors (CM-CMIPS) has been presented in this paper. The pressure sensing structures studied in this work have contained circular and square curved MOSFETs embedded on circular and square silicon diaphragms. The proposed pressure sensors have utilized the piezoresistive effect in MOSFETs as transduction mechanism and have employed current mirror circuits as readout circuits for detecting the externally applied input pressure. This work has included a comparative study for the following six pressure sensing structures: two structures each utilizing a p-type and n-type circular curved channel MOSFET embedded on circular diaphragms, two structures each utilizing a p-type and n-type square curved channel MOSFET embedded on square diaphragms, one structure consisting of both p- and n-type circular curved channel MOSFETs each embedded on two separate circular diaphragms, and the last one consisting of both p- and n-type square curved channel MOSFETs each embedded on two separate square diaphragms. The proposed CM-CMIPS sensors have been designed using standard 5μm CMOS technology. The pressure sensitivities of square-shaped CM-CMIPS employing p-MOS, n-MOS, and CMOS (both p- and n-MOS) structures have been found to be approximately 515, 407, 2151 mV/MPa, respectively, and 505, 661, 2223 mV/MPa, respectively, for the circular-shaped sensors.