Structural and optical properties modification of a-SiC:H by Ga+ ion implantation

Abstract

Thin films (d∼200nm) of hydrogenated amorphous silicon carbide (a-SiC:H), deposited by RF reactive magnetron sputtering, have been ion implanted with high doses (D=1016–1017cm−2) of Ga+ as the implant species. The increased disorder and additional structural modification of a-SiC:H, induced by the implantation of Ga+, results in a considerable change of the optical properties, best manifested by a significant shift of the optical absorption edge to lower photon energies in the results obtained by optical transmission and reflection measurements and as derived from photo-thermal-deflection spectroscopy results. This shift may be attributed both to additional defect introduction and to accompanying structural modification effects, as confirmed by optical absorption measurements in the infra-red region and by Raman spectroscopy results.