HIGH-QUALITY GAAS FILMS ON SI SUBSTRATES GROWN BY ATOMIC HYDROGEN-ASSISTED MOLECULAR-BEAM EPITAXY FOR SOLAR-CELL APPLICATIONS

Minority carrier lifetimes of high-quality n-GaAs heteroepitaxial thin films grown on vicinal Si(100) substrates by atomic hydrogen-assisted low-temperature molecular beam epitaxy (MBE) technique have been inve stigated. Photoluminescence decay characteristics have been evaluated and a minority carrier lifetime of as high as 8.0 ns has been successf ully obtained, which is the highest value reported to date. These resu lts are regarded as of particular importance for high-performance opto electronic device applications especially for tandem solar cells.