Distribution of Electrode Elements near Contacts and Junction Layers in Amorphous Silicon Solar Cell

Abstract

Auger electron spectroscopy with the ion sputter-etching technique and secondary ion mass spectroscopy have been utilized to investigate the depth distribution of Sn and In, electrode elements, in amorphous silicon layers of the photovoltaic device. The comparison of the depth profiles with the cell performances has indicated that the presence of the reduced state of In in both the p and i-layers affects the solar cell performance, but that of Sn does not. It was also shown that layered structure of In–Sn oxide (ITO)/SnO₂ effectively prevents the diffusion of In and accomplishes high cell performances, having the thickness of the SnO₂ layer about 200 Å.