Surface reconstruction and faceting of group [formula omitted] systems — common characteristics of the stable surface structures

Abstract

In the present paper we report on studies of the group III IV(113) systems of Al, Ga and In on Si(113) and Ge(113) with LEED and AES. LEED shows that after being annealed the surfaces of the Al Si , Ga Si and In Ge systems facet to (103), (013), (112) and (115) facets while those of the In Si , Al Ge and Ga Ge systems reconstruct to (113)-(1 × 2). In the entire tested range of coverage and annealing temperature none of the six systems form (113)-(1 × 1). Combining this observation with the results of previous work on group III IV(001) and group III IV(111) we suggest that the common characteristics of all stable surface structures of the III IV systems are: (i) the group 13 atoms form sp 2-like back bonds, and (ii) the surface contains some group IV atoms with a dangling bond. The former is an intrinsic requirement of group III atoms, while the latter facilitates relief of the strain induced by the former, and is thus probably more general.