学習院大学計算機センター 三重大学工学部物理工学科 NTT物性科学基礎研究所 筑波大学物理学系 (株)東芝研究開発センター 学習院大学計算機センター 同志壮大学工学部電気工学科 Computer Center, Gakushuin University Department of Physics Engineering, Mie University NTT Basic Research Laboratories Institute of Physics, University of Tsukuba Research and Development Center, Toshiba Corporation Computer Center, Gakushuin University Department of Electrical Engineering, Doshisha University
A newly developed ab initio-based approach was applied for understanding adsorption-desorption behavior during molecular beam epitaxial growth of GaAs. The ab initiobased approach incorporates free energy of vapor phase; therefore we can calculate how adsorption and desorption depend on growth temperature and beam equivalent pressure (BEP). Versatility of the theoretical approach was confirmed by the calculation of Ga adsorption-desorption transition temperatures and transition BEPs on Ga-rich GaAs (001)-(4×2)β2 surface. Furthermore, in order to check the feasibility of the theoretical approach for prediction of adsorption-desorption behavior of As_2 molecules, the conditions where GaAs(001)-c (4×4) reconstructed structure is stable were investigated by the calculations of stability of As-dimers on the top surface under the various temperatures and BEPs. We also applied the theoretical approach to Ga diffusion length while staying on the GaAs (001)- (2×4)β2 and - (2×4)β1 surfaces and As pressure dependence of GaAs growth rate.