Vicinal Si(100) surfaces under external strain

The phase diagram of vicinal Si(100) surfaces is calculated as a function of misorientation angle, temperature, and applied external strain. It is shown that a change of the applied external strain can lead to a phase transition between the single-layer step surface phase and the double-layer step surface phase. The effect of temperature is shown to be negligible up to 300 K. The order parameter of the surface phase transition is also calculated to make contact with experimental measurements. {} 1996 The American Physical Society.