Direct fusion bonding of silicon to polycrystalline diamond
High temperature fusion of silicon to diamond is reported. Polished, randomly oriented diamond films and unpolished (100) highly oriented diamond films were bonded to single-side polished (100) silicon in a dedicated ultrahigh vacuum bonding apparatus. Directbonding under an applied uniaxial stress of ?32 MPa was observed at temperatures above 950 °C. The bonded interface was examined by scanning acoustic microscopy revealing only partial bonding at fusion temperatures of 950 and 1050 °C. In contrast, complete bonding was evidenced at 1150 and 1200 °C, although cracking of the diamond films became more prominent at these higher fusion temperatures.