Efficient shallow-homojunction GaAs solar cells by molecular beam epitaxy

Abstract

Conversion efficiencies up to 16% at AM1 have been obtained for molecular beam epitaxy (MBE) GaAs solar cells utilizing a shallow‐homojunction n⁺/p/p⁺ structure without a GaAlAs window. The n⁺, p, and p⁺ GaAs layers were all grown by MBE on single‐crystal p⁺ GaAs substrates. Cell metallization was performed by electroplating, and an antireflection coating was formed by anodic oxidation of the n⁺ layer. These cells are the first efficient MBE solar cells of any type to be reported.