Study on MEMS Capacitive Differential Pressure Sensor

Abstract

The design and fabrication of MEMS capacitive differential pressure sensor is reported. Silicon membrane is used as movable electrode. Gold metal film on glass is used as fixed electrode. Anodic bonding is used to bond together the silicon and glass to form the capacitive pressure sensor. The measurement capacitance of the sensors is 5.37 pF at an applied pressure of 0 kPa and 7.26 pF and the full operating range of 40 kPa.The ratio of changed to initial capacitance was 0.35. The error of the MEMS capacitive pressure sensor is less than 4‰ full-scale(FS) by using quadratic curve fitting which can meet most application requirements.

A new automatic measurement system for high-speed railway substructure settlement based on hydrostatic pressure difference levelling

“…A Micro-Electro Mechanical System (MEMS) capacitive differential pressure transmitter with a silicon-glass structure is adopted in this study. 27,28 The working mechanism of MEMS capacitive pressure transmitter is shown in Figure 4. The movable electrode made with silicon film will deform when the pressures on both sides of the silicon film are different, causing change of coupling capacitance between the movable and the fixed electrode.…”