Effects of hydrogen on the barrier height of a titanium Schottky diode onp-type silicon

Abstract

Hydrogen is shown to play an important role in chemically prepared semiconductor surfaces covered by metals. The stability in air of a hydrogen-terminated silicon surface is such that one should be able to form an ideal Schottky contact after metal evaporation. An ideal Ti Schottky contact on chemically prepared p-type silicon is observed after hydrogen is drifted away from the metal-semiconductor interface by reverse-bias low-temperature annealing. It is argued that the observed degraded electrical properties of chemically prepared Schottky contacts result from the effects of the entry of hydrogen into the silicon and hydrogen passivation (deactivation) of dopant atoms.