Abstract
The applicability of the low-field electroabsorption (EA) method to determine the built-in potential of a-Si solar cells has been experimentally demonstrated. As theoretically predicted, plots of the EA signal amplitude versus the bias voltage for various modulation voltages exhibit straight lines intercepting the bias voltage axis at a single definite value corresponding to the built-in potential. The information of the built-in potential thereby obtained is used as a known parameter in the analysis of a-Si solar cells.