New design of micromachined capacitive force sensor

Abstract

Anisotropic etching of a (110) oriented silicon wafer has been used to realize a differential capacitive force sensor. This design is based on a simple concept allowing force to be measured in the plane of the sensor, giving a new and original product in the field of small force measurements. These sensors can be adjusted to measure force in the range 0.01 N to 10 N or, in a low rigidity version, to act as a high precision displacement sensor with an expected resolution of 20 nm. These sensors are planed to be used with a commercial capacitance measurement chip (nominal capacitance: 1 pF, resolution: 1 fF).