STRUCTURE OF SI(100)H - DEPENDENCE ON THE H-CHEMICAL POTENTIAL

The formation energies and atomic structures of the 2 x 1, 1 x 1, and 3 x 1 H-terminated Si(100) surfaces were determined through first-principles total-energy calculations. The ranges of the H chemical potential (mu-H) over which these phases are stable and the equilibrium transition levels were determined. The 3 x 1 (monohydride plus dihydride) phase is found to be stable with respect to separation into the 2 x 1 monohydride and 1 x 1 dihydride phases. A 1 x 1 canted-row dihydride structure is found to be lower in energy than the 1 x 1 symmetric dihydride structure.