SiGe based grating light valves: A leap towards monolithic integration of MOEMS

摘要

The Grating Light Valve (GLV) is a microelectromechanical reflection grating. It operates on the principle of controlled diffraction of incident light due to electrostatic deflection of microbeams, thus producing bright and dark pixels in a display system. This unique approach offers significant advantages compared to other display systems in terms of speed, high optical efficiency, accuracy and ease of manufacturing. At the same time monolithic integration of MEMS on top of CMOS is getting more popular because CMOS-integrated MEMS exhibit less parasitics and have a reduced assembly and packaging cost over hybrid approaches. The relatively low deposition temperature (～450℃) of poly-SiGe compared to poly-Si (～800 ℃) makes poly-SiGe suitable for back end processing. Hence, in this work we report the fabrication and functioning of CVD poly-SiGe GLVs in terms of their response to the amplitude and frequency of the applied actuation voltage.