Measurement of barrier height of Pd on diamond (100) surface by X-ray photoelectron spectroscopy

Highlights: • Metal-semiconductor contacts of Pd/hydrogen-terminated diamond and Pd/oxygen-terminated diamond have been investigated by XPS measurements. • The barrier height for Pd/hydrogen-terminated diamond (ohmic contact) has been measured to be −0.27 eV. • The barrier height for Pd/oxygen-terminated diamond (Schottky contact) has been measured to be 1.73 eV. - Abstract: Barrier height (Φ_BH) values for Pd/hydrogen-terminated diamond (H-diamond) and Pd/oxygen-terminated diamond (O-diamond) have been investigated by X-ray photoelectron spectroscopy technique. H-diamond and O-diamond have been formed on the same diamond (100) layer grown by microwave plasma-enhanced chemical vapor deposition,on which Pd layers have been evaporated. The Φ_BH values for Pd/H-diamond and Pd/O-diamond are determined to be −0.27 eV and 1.73 eV, respectively. It indicates that Pd is a suitable metal for ohmic and Schottky contacts on H-diamond and O-diamond, respectively. The experimental Φ_BH values are in good agreement with the theoretical calculation results.