High efficiency AlGaAs/Si monolithic tandem solar cell grown by metalorganic chemical vapor deposition

Abstract

The improvements of the AlGaAs solar cell grown on the Si substrate and the AlGaAs/Si tandem solar cell by metalorganic chemical vapor deposition have been investigated. The active-area conversion efficiency of the Al0.1Ga0.9As solar cell on the Si substrate as high as 12.9% has been obtained by improving the growth sequence and adopting an Al compositionally graded band emitter layer. A high efficiency monolithic AlGaAs/Si tandem solar cell with the active-area conversion efficiency of 19.9% and 20.6% (AM0 and 1 sun at 27 °C) under two-terminal and four-terminal configurations, respectively, is demonstrated.