COMPUTATIONAL STUDIES OF HYDROGEN-RELATED COMPLEXES IN SEMICONDUCTORS

The two main computational techniques to calculate the microscopic ele ctronic structure of localized defects in solids are reviewed. Cluster calculations using the Hartree-Fock method as well as density-functio nal methods have been widely used to determine the equilibrium structu re of hydrogen and hydrogen-related complexes in semiconductors. Resul ts for the structure of both acceptor-hydrogen and donor-hydrogen pair s in silicon obtained by various methods and at different levels of ap proximations are discussed. Comparisons are made among the calculated vibrational frequencies of hydrogen in these passivation complexes. Th e spin density distribution for bond-centred hydrogen or muonium in di amond is investigated. Owing to the light masses of the proton and the muon it is necessary to average the computed hyperfine parameters ove r the finite extension of the ground-state wave function.