In situ microwave reflectivity measurements of the changes in surface recombination of crystalline silicon induced by the exposure to silane, silane/helium, and helium plasmas

Abstract

Measurements of the transient photoconductivity detected via the change in microwave reflection after laser pulse illumination have been performed during the exposure of crystalline silicon substrates to a pure silane, silane/helium, and pure helium plasma. In all cases, a similar increase of the surface recombination rate is detected immediately after plasma start. While the surface recombination remains high in the case of the pure helium plasma, a decrease of the interface recombination is observed for the pure silane and silane/helium plasma, related to the deposition of hydrogenated amorphous silicon.