Improvement of Integrated Pressure Sensor Systems Fabricated by a Combined CMOS- and MEMS-Technology with regard to Low Pressure Ranges

摘要

Monolithic integrated pressure sensor systems are realized by the combination of two different technologies: CMOS-technology for the electrical part and MEMS-technology for the pressure sensor part. The paper describes the modification of such pressure sensor systems to extend their original nominal pressure range from 600 mbar to the low pressure range of 40 mbar by keeping a sufficient signal to noise ratio and without changing the original mask set. The general methodology is described, and a comparison between theoretical signal evaluation and measurement is given. The study concentrates on the aspect of the different piezocoefficients for various Boron doping concentrations of the piezoresistors.