Lightweight single crystal silicon opto-mechanical structures

Single Crystal Silicon (SCSi) is proving to be an excellent material for the fabrication of lightweight optical components for use in space. As part of the feasibility studies performed prior to space flight applications, it is important to determine the mechanical properties of complex structures manufactured from individual sections of SCSi. As an additional integral building block for future multi-component SCSi structures, the behavior of the McCarter Machine proprietary frit-bonded metal insert technology was examined. Here we report vibration test results, the objective of which was to measure the structural damping characteristics of a typical silicon structure and verify its structural stability after exposure to random vibration. The tests were designed to better understand SCSi, not only as a mirror substrate, but also as a structural material. The success of this test, combined with the already proven McCarter Machine manufacturing techniques, give us the ability to now manufacture new lightweight and stable opto-mechanical assemblies entirely out of SCSi. But since requirements for larger and more sophisticated SCSi structures are limited by the practical size of available boules, the behavior of these frit-bonded SCSi structures needs to be better understood. This understanding will be obtained from planned testing of larger frit bonded SCSi opto-mechanical structural components and assemblies.