Distribution of charged defects in a:SiH n-i Schottky barrier solar cells

Abstract

Nickel n-i Schottky barriers solar cell structures with i-layer thicknesses between 1.0 and 2 μm were characterized by dark I– V's at different temperatures and internal quantum efficiencies (QE). These characteristics were modeled using AMPS (analysis of microelectronic and photonic structures) with charged defect distributions which were derived from results on corresponding i-layer films. This self-consistency was obtained with distributions of gap states which consist of charged defects where dangling bond states are represented by three Gaussians: positively charged D + above mid-gap; neutral D 0 around mid-gap; and negatively charged D − below mid-gap. Excellent fits to the results on Schottky barriers and films can be obtained with these bulk distributions of gap states which is not true for the commonly used two Gaussian D −, D 0 gap state distributions.