ION-IMPLANTED LASER-ANNEALED GAAS SOLAR-CELLS

Conversion efficiencies up to 12% at AM1 have been obtained for ion-implanted laser-annealed (IILA) GaAs solar cells utilizing a shallow-homojunction n+/p/p+ structure without a GaAlAs window. The n+ layer was formed by Se+-ion implantation into the p layer, which was grown epitaxially by chemical vapor deposition on a single-crystal p+ substrate. The implanted layer was annealed, without encapsulation, by scanning with a cw Nd: YAG laser. Cell metallization was performed by electroplating, and an antireflection coating was formed by anodic oxidation of the n+ layer.