A Simple Si Pitch-variable Grating With Shape Memory Alloy Actuator

Abstract

In this paper, a novel bulk grating in which its pitch can be changed by the shape memory alloy (SMA) actuator has been fabricated using silicon micromachining technology. The pitch-variable grating is specially designed to change the pitch easily with small force. The grating is designed to assure moderate stress by finite element method (FEM). Using the reactive ion etching, the grating has a high aspect ratio more than 10. In the diffraction experiment, more than 10% extension ratio has been obtained. The SMA actuator has been installed to the grating. Due to the two-way shape memory effect, the translation mechanism is simple and is easily controlled.