A novel depleted semi-insulating silicon material for high frequency applications

Wafer bonding has been used to manufacture a silicon material intended as substrate for high frequency applications. The space charge regions surrounding the bonded silicon/silicon interface deplete the silicon thereby causing semi-insulating behaviour at high frequencies. The material has been characterized electrically for frequencies up to 40 GHz using metal transmission lines and crosstalk structures on its surface. Measurements on the depleted silicon/silicon structures has been compared to similar measurements on bulk silicon wafers of different resistivities, SIMOX wafers and quartz. The results show that the material has potential to be used at high frequencies.