The sacrificial layer releasing of micro-machined optical-fiber switch with poly-Si torsion mirror

The wet etching process is often used in the sacrificial layer releasing of micro-machined optical-fiber switch with poly-Si torsion mirror. After the sacrificial layer release and during wafer drying, however, the surface tension of the flowing liquid produces pulling forces on suspended structure which causes stiction effect and leads to the microstructure losing efficacy. This paper introduces replacement and different wet etching methods to resolve the stiction problem and obtain satisfactory microstructures in the process of release of the sacrificial layer for micromachined optical fiber switch with poly-Si torsion mirrors.