Reaction kinetics of hydrogen-gold complexes in silicon

We report studies of hydrogen-gold (Au-H) complexes in gold-doped silicon formed after hydrogen injection during wet chemical etching. Using deep-level transient spectroscopy we find three deep levels that most likely belong to the same Au-H center, labeled G. This electrically active Au-H center transforms irreversibly into an electrically inactive Au-H complex during annealing at temperatures above 150 °C. This transformation seems to occur only when excess atomic hydrogen is present in the sample in the vicinity of the Au-H complexes. Based on the annealing kinetics we tentatively assign the active complex to a Au-H pair and the passive one to Au-${\mathrm{H}}_2$.