Studies on an (NH₄)₂S_x-Treated GaAs Surface Using AES, LEELS and RHEED

Abstract

Surface properties of (NH 4 ) 2 S x -treated GaAs (100), (111)Ga and (1̄1̄1̄)As planes were studied by means of Auger electron spectroscopy (AES), low-energy electron energy loss spectroscopy (LEELS) and reflection high-energy electron diffraction (RHEED). We found that oxide-free and sulfur-terminated GaAs surfaces produced by the (NH 4 ) 2 S x treatment provided the reduction of interface state density. Furthermore, comparison of various planes revealed that (i) sulfur atoms could combine with both Ga and As and (ii) bonding between Ga and S was stronger than that between As and S.