Corrugation reduction in periodically inverted GaAs by molecular beam epitaxy growth using arsenic dimers

Abstract

Molecular beam epitaxy (MBE) regrowth of GaAs on periodically inverted GaAs(100) substrates using arsenic dimers (As2) was studied. We found that we can reduce corrugations on the regrown GaAs by MBE growth using As2 at considerably higher substrate temperatures (∼450 °C) than in the case of growth using arsenic tetramers (∼300 °C). This result indicates that As2 MBE regrowth can be used to fabricate highly efficient GaAs/AlGaAs wavelength conversion waveguiding devices owing to a reduction in the propagation losses caused by interface corrugations. We also estimated the diffusion lengths of Ga atoms coexisting with As2 on GaAs(100) surfaces from experimental thickness variations on the basis of a diffusion equation analysis.