GAAS INITIAL GROWTH ON INAS (001) VICINAL SURFACES OBSERVED BY SCANNING-TUNNELING-MICROSCOPY

GaAs initial growth on InAs surfaces misoriented by 2 degrees toward the [110] and [1 $($) over bar$$ 10] directions was investigated by scanning tunneling microscopy (STM). In the STM images of both InAs vicinal surfaces after GaAs deposition, white lines running in the [1 $($) over bar$$ 10] direction, corresponding to the grown GaAs surface, were observed. Almost all of the lines were attached only to steps running in the [110] direction (B-type steps) on both InAs surfaces; that is, the lines were seldom attached to steps running in the [1 $($) over bar$$ 10] direction (A-type steps). These results indicate that the B-type steps are more favorable for the sticking of deposited Ga atoms than the A-type steps during GaAs initial growth on InAs vicinal surfaces.