Sublimation of a heavily boron-doped Si(111) surface

We investigated sublimation of a heavily boron-doped Si(lll) surface in comparison with that of a normal Si(lll) surface in ultrahigh vacuum. Step spacing during step-flow sublimation is analyzed as a measure of the adatom diffusion length using >50-mu m-wide (111) planes created at the bottom of craters. On the heavily doped 1x1 surface, the step spacing is smaller and the step-spacing transition (or "incomplete surface melting'' transition) temperature is 60 degrees higher than those on the normal 1x1 surface. These results are interpreted in terms of the effect of boron at S-5 substitutional sites. Below 1100 degrees C, the sublimation of heavily doped surface on the wide terrace turns into a two-dimensional vacancy-island nucleation mode from step-flow sublimation observed above 1100 degrees C. [S0163-1829(98)05243-6].