SOD wafer technology
Silicon-on-diamond (SOD) structured wafer with 4-inch diameter was fabricated by the technologies of CVD diamond deposition, Si wafer bonding and thinning. Diamond thin film with high quality and low interface state density was uniformly deposited on Silicon (001) substrate, continuous H+ ion bombardment to as-grown film surface under DC bias was performed to decrease the intrinsic tensile stress in the film. Bonding and thinning technology of Si wafers were applied for forming the holder and device layer of SOD structured wafer. The 54HC139 SOD logical circuits were fabricated on SOD wafer to evaluate the properties of diamond layer in SOD structured wafer. The results present that SOD circuits have obvious ability of irradiation hardness to ?-ray total and instantaneous doses than those of bulk Si circuits, and it can also work at high temperature of 300C. The SOD circuits can keep normal logical function at the total dose of 106 Rad(Si) and instantaneous dose of 1011 Rad(Si). The properties of irradiation hardness and high temperature work for SOD circuits can be attribute to the high hole mobility and thermal conductivity of diamond film.
silicon-on-diamond irradiation hardness diamond film integrated circuits