MEMS Piezoresistive Cantilever Fabrication And Characterization

Abstract

A microcantilever array chip made with Micro-Electro-Mechanical System (MEMS) technology has been demonstrated to develop as a biosensor device. This chip includes four gold-covered and embedded polysilicon wire with microfabricated Si beams. The polysilicon coat serves as a piezoresistor, and changes in resistance due to compressive and tensile forces indicate microcantilever deformation. The relationship between initial resistance and microcantilever deflection demonstrates that this device has a detection range of 0-56kΩ. The investigation of the microcantilever response to biotin immobilisation revealed that resistance change caused by Biotin absorption can be observed and reaches a degree of amount independence at Biotin concentrations higher than 80pg/ml. The results suggested that this device could be developed as a piezoresistive-based microcantilever biosensor.