STEP RELAXATION AND SURFACE STRESS AT H-TERMINATED VICINAL SI(111)

Atomic relaxations at a newly discovered step structure on H-terminated Si(111) surfaces, miscut in the [112BAR] direction and prepared by a new wet chemical technique, are quantified by first-principles calculations and infrared absorption measurements. A strong H-H steric interaction within this step structure produces a 20-degrees Si-H bond rotation and a large (almost-equal-to 0.15 angstrom) displacement of the adjacent step-edge silicon atoms. The range of the perturbations, however, remains confined to almost-equal-to 10 angstrom of the step edge.