Technologies for Low Power Density Phased Array Radars

This Phase-II SBIR proposal proposes the use of a new class of diamond-seeded solid-state material system for the manufacture of virtually all packaged intense heat-generating solid-state electronics in X-band and Ballistic Missile Defense radar components and systems. In this proposal wherein much preliminary (also MDA-funded) work has been demonstrated hitherto by the authors, Gallium Nitride-on-SiC power amplifiers in X-band radar are replaced with GaN-on-Diamond power amplifiers to enable nearly total and immediate heat extraction from the device’s active region. This proposal is focused on producing a 3” GaN-on-Diamond FET wafer, as well as 5 W/mm GaN-on-Diamond FET devices. Polycrystalline free standing CVD diamond – nature’s most efficient thermal conductor – enables nearly perfect heat extraction from a “hot” device, owing to the extreme thermal conductivity of diamond (GaAs, Si, and SiC are 35W/m/K, 150W/m/K and 390W/m/K respectively; diamond ranges from 1200-2000 W/m/K depending on quality). In the proposed scheme, the device’s active epitaxial layers are removed from their original host substrate and transferred to a specially treated low-cost CVD diamond substrate using a proprietary low-cost manufacturable scheme. The semiconductor-on-diamond technology proposed here may be applied to Si, GaAs, GaN, SiC, SiGe, etc. at up to 8” in wafer diameter.