Space-charge limited current in the series resistance of GaAs solar cells

Abstract

We report the observation of space-charge limited current in the current–voltage characteristics of GaAs solar cells as evidenced by an abrupt decrease in the series resistance, a concurrent steep increase in the dark current at a threshold voltage and the observation of a quadratic dependence of the dark current on the voltage across the series resistance above threshold. The abrupt decrease in the series resistance at threshold, results in the observation of negative differential resistance and a subsequent hysteresis in the current–voltage characteristics. Auger electron spectroscopy analysis shows that the space-charge limited current can be attributed to a thin insulating CrAs layer at the contact/semiconductor interface.