NOVEL SURFACE PASSIVATION SCHEME FOR COMPOUND SEMICONDUCTOR USING SILICON INTERFACE CONTROL LAYER AND ITS APPLICATION TO NEAR-SURFACE QUANTUM-WELLS

A novel passivation scheme using an ultrathin molecular beam epitaxy ( MBE) silicon interface control layer (ICL) and an ultrathin silicon ni tride layer is investigated for use in the passivation of compound sem iconductor quantum structures. Process optimization was performed by i n-situ. X-ray photoelectron spectroscopy (XPS) and electrical characte rization of the insulator-semiconductor interface formed on In0.53Ga0. 47As. A drastic reduction of interface state density into the 10(10) c m(-2) . eV(-1) range was obtained under optimum condition. The passiva tion scheme was then applied to passivation of Al0.3Ga0.7As/GaAs/Al0.3 Ga0.7As near-surface quantum wells. Remarkable recovery of photolumine scence (PL) intensity was observed upon application of the present pas sivation scheme to the barrier surface, which was consistent with the reduction of surface states.