Industrial applications experts in the semiconductor and aeronautical fields are specifying single-crystal sapphire plates and windows over 14 in. in diameter for their product designs.
In addition, the semiconductor community is scaling up the size of its silicon and gallium arsenide wafers. Subsequently, sapphire wafer carriers and other mechanical parts must follow in form.
Large Sapphire Optics suit mechanical applications.
The aerospace industry is now turning from non-sapphire to sapphire windows because of the material's robust nature and good optical properties. These new large-dimension standards required the scale-up of the heat exchange method (HEM) of crystal growth, as well as fabrication processes that accommodate the new regime of components.
Crystal Systems now offers 15" diameter sapphire plates in both optical and mechanical qualities. Sapphire has a low coefficient of thermal expansion, operating temperature above 2000° C and measures 9 on the Mohs scale. These characteristics combine to make sapphire the perfect choice for harsh environments where material failure is unacceptable. Custom sizes and shapes available.
Source: http://www.crystalsystems.com/