Title: Development of Immersion Gratings to Enable a Compact Architecture for High Spectral and Spatial Resolution Imaging
Presenting Author: Cynthia Brooks
Organization: The University of Texas at Austin
Co-Author(s):
Daniel T. Jaffe, The University of Texas at Austin; Daniel W. Wilson, Richard E. Muller, Jet Propulsion Laboratory

Abstract:
Immersion grating spectrographs offer the opportunity of greatly decreasing the volume and mass of near infrared instruments while allowing high spectral and spatial resolution. The University of Texas at Austin (UT) and Jet Propulsion Laboratory (JPL) have collaborated in the past to build silicon immersion gratings for astrophysics applications. The requirements for Earth Science missions necessitate changes in the design of the gratings, which in turn require new methods of building these gratings. In this collaboration we designed a prototype instrument and defined the immersion grating specifications. We investigated three methods of building these gratings in monolithic silicon (contact lithography, binary electron beam lithography, and grayscale lithography), and we tested gratings built with each method. We also investigated the feasibility of building gratings in thin silicon material and bonding to a pre-cut silicon prism. We will present our efforts to build and thoroughly test a set of silicon immersion gratings customized for the needs of Earth observation systems.