Abstract
We have used microprobe RHEED and a convex curved substrate to study the terrace-width dependence of equilibrium surface structures on vicinal Si(001). We observe a transition from double to single domains of the 2×1 reconstruction in periodic [110] step arrays that occurs gradually over a range of miscut angle from 0° to 5°, and is independent of temperature over the measured range of 500–800 °C. Possible mechanisms for this transition and its relation to a transition in step heights are described.