CMOS compatible capacitive pressure sensor with read-out electronics

The fabrication of capacitive pressure sensors using silicon integrated circuit processing is described. The pressure sensors were fabricated using planar etch processing techniques. This results in very small sensors having membrane diameters between 59 micrometer and 150 micrometer. The pressure dependence was studied up to 5 bars. Concepts for on chip signal conditioning by using the switch-capacitor methods are given.