Structure of Ga-stabilized GaAs(0 0 1) surfaces at high temperatures

We have studied the atomic structure of the Ga-stabilized GaAs(0 0 1)-c(8×2) surface using rocking-curve analysis of reflection high-energy electron diffraction (RHEED). The c(8×2) surface is stable only at temperatures higher than 600 °C, but changes to the (2×6)/(3×6) structure at lower temperatures. The atomic structure of the c(8×2) surface at high temperatures is basically the same as that determined by the analysis at room temperature. We propose that the surface atomic configurations are locally fluctuating at high temperatures.