Interactions of vicinal Si(100) surfaces with group V elements and Monte Carlo study of metal surfaces and metal clusters using semiempirical potentials

Abstract

[Chapter Ⅰ. Atomic-step Rearrangement on Si(100)by Interaction with Antimony] We have observed the various step structures of Sb : Si(100) surfaces with a miscut of 2°by controlling kinetics and thermodynamics. In the kinetic regime of 375 K the 2×1 single-domain or the 1×2 one was observed depending on Sb coverage, while in a thermodynamic regime above 900 K the double-domain with symmetric domain population is observed. Also, the 1×2 surface has undergone the successive structural phase transition from the (2×1) to the (2×2) and the (2×2) to the c(4×4) phase as the 1×2 surface was annealed at 1200 K. These successive structural phase transitions are irreversible. The single-domain formation was explained by the vacancy mediated mixing model, which can explain consistently the unexpected coverage of 1.4 ML of 1×2 single-domain at low temperature and the c(4×4) reconstruction. The symmetric double-domain structure was discussed based on the anisotropic stress tensor and the elimination of rebond by displacing the Si atom with Sb at the $S_B$ step. Surface mixing, anisotropic stress, and the elimination of the rebond at the $S_B$ step are expected to be the main causes of the observed domain structures and reconstructions. [Chapter Ⅱ. Reconstructions and Step Structures on Vicinal Si(100) surfaces by Interaction with Bi] Reconstructions and step structures on vicinal Si(100) surfaces by interaction with Bi are studied under diverse experimental conditions with varying substrate temperatures and Bi coverages. The various reconstructions and the step structures on Bi:Si(100) are observed depending on the substrate temperatures and Bi coverages. At low coverages, (2×2) and c(4×4) phase are observed below 350 K and at about 400 K, respectively. For the saturated surfaces, (2×1) and high order (2×7) phase are observed below 400 K and at 500~800 K, respectively. Comparing the formation temperatures for each phase, it can be concluded that the c(4×4) structure has en...