Structure of the boron-hydrogen complex in crystalline silicon

Abstract

The lattice site occupied by the boron and hydrogen atoms in hydrogenated crystalline silicon is investigated by use of ion channeling and nuclear-reaction analysis. After hydrogenation, boron atoms are found to be displaced from substitutional sites. Analysis of the data indicates that the shift is 0.22\ifmmode\pm\else\textpm\fi{}0.04 \AA{}. The hydrogen atoms are found to preferentially occupy the bond-center site. These findings are consistent with a structure for the boron-hydrogen complex in which the hydrogen atom occupies a site between a silicon and a boron atom, while the boron atom relaxes back towards a threefold-coordinated position. The data are compared with recent predictions of the structure of the B-H complex in silicon.