Scanning Blazed-Gratings for High-Resolution Spectroscopy

J.T. Nee, K.Y. Lau, R.S. Muller
1998 1998 Solid-State, Actuators, and Microsystems Workshop Technical Digest   unpublished
We have used anisotropic etching and subsequent polysilicon surface micromachining in a new process to produce actuated blaze gratings. Using the etch properties of KOH in single-crystal (100)-oriented silicon, we obtain repeatable 54.7° blaze angles in the gratings by making use of the etched grooves as a mold for LPCVD-deposited polycyrstalline silicon. The designer can vary the grating period using conventional lithography techniques. After producing the grating structure in conventional
more » ... in conventional surface micromachining steps, it is "folded" out from the surface and actuated by an on-chip electrostatic drive. We present experimental results made using prototype polysilicon gratings having an 11.7 µm period in a square pattern 700 µm on a side. We have also produced and assembled 1.3 mm-tall grating structures that are now being tested. The polysilicon plates are mounted on torsion bars and actuated by electrostatic combdrives. If operated as high-order reflective gratings, these prototypes can be used to build integrated spectrometers with a resolving power of 1470 (wavelength resolution of approximately 0.4 nm). 0-9640024-2-6/hh1998/$20©1998TRF
doi:10.31438/trf.hh1998a.5 fatcat:h7wrm3xkwvgh3odwbi2dxumdlu