Gallium arsenide thermal properties

Gallium arsenide is epitaxially deposited on a silicon substrate and the resulting composite combines the mechanical and thermal properties of silicon with the photonic capabilities and fast electronics of gallium arsenide. 

The key properties in thermal management are the thermal conductivity and the coefficient of thermal expansion of polymer, metal, and ceramic matrix composites. Highly graphitic carbon whiskers offer major improvements in the thermal conductivity and density of a heat sink, but their thermal conductivity is highly anisotropic and their thermal expansion does not match that of circuit material such as silicon or gallium arsenide. Diamond fibers far exceed the thermal conductivity of graphitic carbon fibers. 

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