Development of high-yield fabrication technique for MEMS-PhC devices

Abstract

We propose a high-yield fabrication processing technique for the MEMS (micro electro mechanical system) modulators integrated with two-dimensional photonic crystal waveguides. Polysilicon microactuators for evanescent modulation was successfully developed by using the vapor hydrofluoric-acid releasing technique for stiction-free sacrificial release, during which the SOI photonic-crystal waveguides were protected under the LPCVD silicon nitride film. Post-release anneal was found to be needed to remove the byproduct made by the reaction of hydrofluoric acid with silicon nitride film. Preliminary optical modulation result (-2dB modulation with 86V) was experimentally obtained.