MBE Growth of AlGaAs Using Sb as a Surfactant

摘要

We have employed a surface segregating population of Sb as an isoelectronic surfactant during solid-source molecular beam epitaxy (MBE) of AlGaAs layers. A steady-state population of Sb was maintained at the AlGaAs growth surface by providing a continuous Sb_2 flux to compensate for loss due to thermal desorption. A significant improvement in the optical quality of AlGaAs layers was observed by photoluminescence. Sharper GaAs QW PL lines also indicate smoother inverted (GaAs on AlGaAs) interfaces when the Sb surfactant is employed. These improvements may be attributed to a reduced incorporation of impurities and point defects, and/or improved surface diffusion kinetics during AlGaAs MBE.