Hydrogen–oxygen interaction in silicon at around 50 °C

Abstract

Formation kinetics of oxygen-hydrogen ͑O-H͒ complexes which give rise to an infrared absorption line at 1075.1 cm Ϫ1 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°C͒ in diffusion from H 2 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 0.28Ϯ0.02 eV. An activation energy for migration of hydrogen-related species responsible for the formation of the O-H complexes was found to be 0.78Ϯ0.05 eV. It was shown that atomic hydrogen and H 2 *, 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 (H 2 ) 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 Ϫ1 .

The Interaction of Hydrogen with Deep Level Defects in Silicon

“…It is not easy to give a convincing explanation of the effect of annealing unless interstitial molecules are involved -even though they are unexpectedly infrared active. The annealing studies give a binding energy of the molecule to oxygen to be 0.28 ± 0.02 eV and a barrier for molecular diffusion to be 0.78 ± 0.05 eV [111]. No DLTS lines have been correlated with these defects [110], consistent with the view that they are electrically inactive.…”

“…Early work identified an infra-red active mode at 1075.1 cm −1 in Cz-Si into which hydrogen had been diffused at high temperature, which anomalously shifted upwards to 1076.3 cm −1 in deuterated samples [109,110,111]. This implies that hydrogen is part of the defect.…”

“…The molecule was found to be nearly degenerate in both the [100] and [111] alignments, with a 0.56 eV barrier to diffusion.…”

“…The earliest were performed were Corbett et al [99] using the MNDO approach with a very small cluster (Si 14 H 20 ). The hydrogen molecule was found to be most stable at the T site, aligned along [111]. The energy required to dissociate the molecule into two H 0 atoms at M sites (see Fig.…”

Response to “Comment on ‘Hydrogen–oxygen interaction in silicon at around 50 °C’ ” [J. Appl. Phys. 87, 4635 (2000)]

“…3 or by high temperature ͑1200°C͒ in-diffusion from H 2 gas ambient followed by quenching in Ref. 2. It is thought, however, that hydrogen is introduced into the Si lattice as hydrogen atoms in both cases.…”