Hydrogen–oxygen interaction in silicon at around 50 °C

Abstract

Formation kinetics of oxygen–hydrogen (O–H) complexes which give rise to an infrared absorption line at 1075.1 cm−1 have been studied in Czochralski-grown silicon crystals in the temperature range of 30–150 °C. Hydrogen was incorporated into the crystals by high temperature (1200 °C) in diffusion from H2 gas. It was found that the observed kinetics can be explained as being due to an interaction of mobile neutral hydrogen-related species with bond-centered oxygen atoms. The binding energy of the O–H complex was determined to be 0.28±0.02 eV. An activation energy for migration of hydrogen-related species responsible for the formation of the O–H complexes was found to be 0.78±0.05 eV. It was shown that atomic hydrogen and H2*, a complex containing two hydrogen atoms, one at bond-centered site and another one at antibonding site, cannot account for the hydrogen–oxygen interaction considered. Hydrogen molecules (H2) located at tetrahedral interstitial site are suggested to be the species which interact with interstitial oxygen atoms and form the complex giving rise to the absorption line at 1075.1 cm−1.