Electronic structures of hydrogenated and oxygenated boron-doped diamond films

The hydrogenated and oxygenated boron-doped diamond films have been prepared by hydrogen-plasma treatment and boiling in the strong acids, respectively. By means of the X-ray photoelectron-spectroscopy and contact angle measurements, the two surface-terminated diamond films have been evaluated. The scanning tunneling spectra have been measured by scanning probe microscope. The results indicated that for the hydrogenated diamond surface, the surface energy bands bend downwards and there exists a shallow acceptor above the valence band maximum. However, the surface energy bands for the oxygenated film bends upwards and its band gap is wide and clean. The conduction mechanisms for the two surface-terminated diamond films have been discussed.