Ohmic contacts on diamond by B ion implantation and Ti-Au metallization

Low-resistance ohmic contacts have been fabricated on a natural IIb semiconducting diamond crystal and on undoped polycrystalline diamond films by B ion implantation and subsequent metallization with a Ti-Au bilayer metallization. A high B concentration of approximately 7*10/sup 20/ cm/sup -3/ at the surface was obtained by ion implantation, a post-implant anneal, and a subsequent chemical removal of the graphite layer that resulted from the radiation damage. A bilayer metallization of Ti followed by Au annealed at 850 degrees C yielded a specific contact resistance value on the order of 10/sup -6/ Omega -cm/sup 2/ for chemical-vapor-deposition-grown polycrystalline films and on the order of 10/sup -5/ Omega -cm/sup 2/ for the semiconducting natural crystal.<
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