An innovative Pirani pressure sensor

Abstract

A conventional Pirani vacuum sensor is converted into a device able to measure high gas pressure. By referring to infinite pressure, heat-loss change from the reference to a measured pressure induces electrical signal on the resistive sensor. 0.3 /spl mu/m shallow gap is formed for the floating microsensors to increase its sensitivity. This results in a measurable range from 10/sup 5/ down to 10/sup -1/ Torr. The thermal microsensor differs from the piezoresistive or capacitive type in sensing mechanisms. It also has advantages in smaller size and simpler structure.