Investigation of Surface Passivation Effect of a-SiNx:H on a-Si:H by Photothermal Deflection Spectroscopy

Abstract
Optical absorption of surface- and interface-states in a-Si:H and a-SiN x :H (x=1.2 and 1.7) films was measured by photothermal deflection spectroscopy. The surface-state absorption of a-Si:H was reduced by passivation of the a-SiN1.7:H or a-SiN1.2:H layer. The surface absorptions of a-SiN1.7:H and a-SiN1.2:H are lower than that of a-Si:H. The origin of free surface absorption of a-Si:H was discussed in terms of the native oxide layer.