Low-Stress Silicon Cladding for Silicon-Carbide Mirrors

Silicon carbide (SiC) has recently become an attractive replacement for berrilium in missile interceptor mirror applications. However, because of the difficulty in grinding silicon carbide and the potential for micro-porosity in the material, many types of SiC require the application of a relatively soft silicon layer for final figuring and polishing. Surface Optics Corporation (SOC) will develop and demonstrate a low-stress, polishable, silicon cladding for SiC mirrors using an ion-assisted deposition technique. In Phase I, SOC will fabricate silicon films and characterize the films for residual stress and polishability. In Phase II, the designs will be optimized and the research will be extended to include environmental exposure testing to ensure long-term stability of the materials.