Phase-Locked Epitaxy Using RHEED Intensity Oscillation

Abstract

Long lasting RHEED oscillations during MBE growth of GaAs and Al x Ga 1- x As are observed. Using these oscillations, accurate measurements of GaAs, Al x Ga 1- x As growth rates and the Al mole fraction x were performed during the growths. The phase of the RHEED oscillations was analyzed by computer and molecular beam shutters were operated at a particular phase. This computer controlled phase-locked epitaxy (PLE) was applied to grow precisely defined (GaAs) 2 (AlAs) 2 bi-layer superlattices. Raman scattering spectra showed split lines characteristic of superlattices. This PLE method is invulnerable to molecular beam fluctuations.