Design, fabrication and characterization of a fully programmable micro diffraction grating

In this paper, we present the development of a fully programmable micro diffraction grating (FPMDG) in which each micromirror in a 1D array can be individually deflected out-of-plane by up to 1μm. The 120μm wide and 700μm long mirrors are designed to remain optically flat during actuation. The peak-to-valley curvature of a fully actuated micromirror is shown to be 10nm equal to a radius of curvature (ROC) of 7m. The FPMDG is fabricated using anodic waferbonding to combine a prepatterned electrode array with a low-stress, single-crystal silicon (SCS) optomechanical layer. Serpentine flexures reduce the required operating voltage to <;30V while permitting rigid micromirrors and resonant frequencies >10kHz.