Determination of built-in-potential in N-I-P a-Si:H solar cells

This paper describes a simple method to evaluate built-in-potential of P-N junction a-Si:H solar cells. Built-in-potential (V
bi
) was calculated from photovoltage-current characteristics at various temperature and illumination levels. Results from two independent, experimental techniques agree extremely well. V
bi
= 1.02 eV ± 0.02 eV was obtained for a N-I-P cell having V
oc
= 650 mV under AM1 illumination.