Optical Grade Sapphire Manufacturing Growth Process for IR Window Applications

Sapphire Systems Inc. will demonstrate a stable, repeatable process for growing sapphire plates which will finish to windows 14” x 20” x 0.8". In Phase I, plates will be grown in the A-plane and C-plane orientations which are 12.5" x 20" x 7/8". Current production experience suggests that the plates will have clean, clear surfaces, requiring minimal grinding and polishing. One of these A-plane plates will be fully finished and optically characterized to Air Force specifications. Using the data from this work, a plan will be formulated for scaleup to grow optical-quality sapphire plates on a commercial scale which will finish to 14" x 20" x 0.8" and larger. A full production path will be outlined to allow drop-in replacement of the windows for the end user. BENEFIT: Sapphire windows are urgently needed for the Electro-Optical Targeting System for the Joint Strike Fighter. A high-quality, reasonably-priced source will reduce risk for this critical platform. Large sapphire windows are also needed for future Air Force and other DoD platforms. The motivation to replace windows made from costlier, softer materials may be significant as well. There is significant demand for sapphire plate for transparent armor. While this is primarily military at the moment, with better production methods and lower costs, sapphire could become the material of choice for civilian applications as well. It is likely that over the next decade, IR vision systems will become standard on commercial aircraft worldwide. Each of these systems requires a sapphire window. The semiconductor industry, a large user of sapphire windows and hardware, is moving towards 300 mm-diameter wafers. The tools to handle these wafers will require significant quantities of large sapphire windows and plate.