Development of novel bulk micromachined parallel in-plane electrothermal actuators

This paper reports the development of novel electrothermal actuators with large in-plane displacement designed for microelectromechanical system (MEMS)-based pitch-tunable diffraction grating (MPDG) for beam steering applications. The actuators consist of two sets of parallel electrothermal beams that pull and push a lever to produce large in-plane displacement. They have been fabricated using bulk micromachining technique and tested. Experimental results show that the actuators generate large unloaded in-plane displacements of up to at a driving voltage of . They demonstrated a loaded displacement range of up to at , generating up to of force with minimal out-of-plane movement. The results show that the actuators have the desired capability to enable MPDG for beam steering applications. Beam steering angles of , and at the 1st, 2nd and 3rd diffraction orders are achievable at driving voltage with the reported actuators.