An isothermal etchback-regrowth method for high-efficiency Ga1−<i>x</i>Al<i>x</i>As-GaAs solar cells

Abstract

High-efficiency p-Ga1−xAlxAs, p-GaAs, n-GaAs solar cells are made by isothermally soaking n-GaAs substrates in an undersaturated Zn-doped Ga-Al-As melt. This one-step growth procedure produces a graded band gap p-Ga1−xAlxAs layer 0.2–0.4 μm thick. Efficiencies of 18.5% AM0 and 21.9% AM1 have been measured.