Spectral Response of Solar Cells

Abstract

An analysis of the spectral response of a solar cell is given which includes the effect of the electric field present in the diffused surface region. Results are presented which show the variation of response with junction depth and with carrier lifetime in both surface and bulk regions. By curve fitting, it is found that in a typical silicon cell the bulk lifetime is in the range 1–15 μsec, while the surface region lifetime is between 10⁻⁹ and 10⁻¹⁰ sec. Bombardment with a total flux of 3.3×10¹⁴ electrons/cm² of 2‐Mev electrons reduced the n region lifetime by a factor of 300, and the p region lifetime by a factor of 6 in a particular case.