Regular step arrays on silicon

Abstract

Highly regular arrays of steps are produced on vicinal Si(111)7×7. The step edges are atomically straight for up to 2×104 lattice sites. The terraces are single domain, which produces a minimum kink width of 2.3 nm (half a 7×7 unit cell) and thus a high barrier for creating kinks. Criteria for obtaining optimum step arrays are established, such as the miscut [≈1° towards (1̄1̄2)] and an annealing sequence which passes through step bunching regions quickly.