Effect of Ga predeposition layer on the growth of GaAs on vicinal Ge(001)

We report a detailed study of molecular beam epitaxial growth of GaAs films on vicinal Ge(0 0 1). Reflection high-energy electron diffraction was used to examine the atomic structures of the epitaxial surfaces. By using RHEED technique we show that clean Ge(OO 1) vicinal surface has (1 x 2) single-d omain reconstruction and consists of double-layer steps. After the depositi on of Ga submonolayer coverage, transformation from double to single-layer stepped surface was observed. Transmission electron microscopy reveals a hi gh density of anti-phase domains in the GaAs epitaxial films grown on singl e-stepped Ga covered Ge(0 0 1) vicinal surfaces and anti-phase domain free GaAs was grown on a double-layer stepped clean Ge(0 0 1). (C) 1999 Elsevier Science B.V. All rights reserved.