The effects of the initial surface reconstruction of GaAs upon the microscopic surface structures of the Si ICL and upon the macroscopic electronic properties were studied in situ, using an ultra-high-vacuum multi-chamber system. Thus, (2 x 4) and c(4 x 4) GaAs surfaces were prepared by molecular beam epitaxy. Surface structures and compositions were studied by ultra-high vacuum scanning tunnelling microscopy and X-ray photo-electron spectroscopy. Macroscopic electronic properties of the passivated surfaces were investigated using X-ray photo-electron spectroscopy band bending measurements, ultra-high vacuum contact-less capacitance-voltage measurements and ultra-high vacuum photoluminescence methods. The Si layer grown on the initially reconstructed c(4 x 4) surface was found to be more ordered and flatter than that grown on the initially reconstructed (2 x 4) surface. This difference showed a strong correlation with the macroscopic electronic properties, after a passivation process, as measured using X-ray photo-electron spectroscopy, ultra-high vacuum contactless capacitance-voltage and photoluminescence techniques. The results indicated the importance of the 2-dimensional order on the Si-deposited surfaces for successful passivation.

Effects of Initial Surface Reconstruction on Silicon Interface Control Layer Based Passivation of (001) GaAs Surfaces Studied in an Ultrahigh-Vacuum Multichamber System. M.Mutoh, N.Tsurumi, H.Hasegawa: Japanese Journal of Applied Physics, 1999, 38, 2538-43