Tunable light grating integrated with high-voltage driver IC for image projection display

This paper presents a monolithic integration technique of MEMS grating light valves with high-voltage (40 V) driver circuits that target for image projection display devices. Driver circuits were prepared°n an 8-μm-thick SOI (Silicon-on- Insulator) wafer by the DMOS (Double-diffused Metal Oxide Semiconductor) processes, after which the MEMS grating were integrated in the identical SOI layer by post-processing using the DRIE (Deep Reactive Ion Etching). In°ur work,°ptical light angle is modulated by changing the period°f the MEMS grating pixel by means°f electrostatic actuation. Optical diffraction angles°f 6.6° (OFF-state) and 3.3° (ON-State) were obtained with drive voltage°f 0 V and 40 V, respectively.