Scanning tunnelling microscopic data were presented which illustrated the evolution of the de-capped (001) surface, following annealing at temperatures ranging from 450 to 540C. After annealing at 450C, the (2 x 4) reconstruction was composed of kinked rows of two As dimer unit cells. Following annealing at temperatures ranging from 475 to 500C, small isolated regions of (4 x 2) reconstruction were visible; with a considerable increase in the disorder of the remaining (2 x 4) reconstructed areas. Annealing at higher temperatures caused the (4 x 2) structure to become increasingly predominant. Significant differences were noted in the surface morphology as a function of annealing time. The images of the (4 x 2) surface were similar to those which had been reported elsewhere, but a different structural model was proposed here.

P.Moriarty, P.H.Beton, Y.R.Ma, A.W.Dunn, M.Henini, D.A.Woolf: Journal of Vacuum Science and Technology B, 1996, 14[2], 943-7