The use of  in situ  scanning tunnelling microscopy, at temperatures of up to 600C, provided atomic-scale evidence which demonstrated that the formation of stacking-fault half-units played a leading role in the growth, of 7 x 7 reconstructed domains on (111) surfaces, from the 1 x 1 phase during supercooling. This then accounted for the fact that all of the 7 x 7 reconstructed areas on (111)Si supercooled surfaces formed triangular domains with vertices which pointed in <112> directions. The scanning tunnelling microscopic data suggested that the formation of the stacking fault half-unit involved the construction of dimer chains and corner holes. A similar leading role of the half-unit was deduced to be the basis for the growth of 5 x 5 and 9 x 9 metastable structures.

T.Hoshino, K.Kumamoto, K.Kokubun, T.Ishimaru, I.Ohdomari: Physical Review B, 1995, 51[20], 14594