Low 1∕f noise, full bridge, microcantilever with longitudinal and transverse piezoresistors

Abstract

This paper reports on low 1∕f noise, low corner-frequency, piezoresistive microcantilevers suitable for static and slowly time varying, force and displacement sensing applications such as chemical and biosensing. We demonstrate a full bridge, piezoresistive cantilever with greater than 140dB dynamic range, a noise amplitude spectral density floor of 3.7nV∕V√Hz at 0.1Hz. At 1.0Hz, the noise spectral density is 1.2nV∕V√Hz equivalent to 10pN∕√Hz or 5pm∕√Hz. The force resolution over the frequency band of 0.1–100Hz is 100pN.