It was recalled that the high-temperature annealing of Si/SiO2/Si structures in inert atmospheres resulted in degradation of the oxide layer and in the creation of electron and hole traps. Current understanding of the basic mechanisms which operated in such structures and which could result in point-defect generation was reviewed. On the basis of electron spin resonance and infra-red absorption data it was demonstrated that, in low O-content float-zone Si substrates, annealing of the structures at high temperatures resulted in the gettering of O from the oxide, and into interstitial sites in the Si substrate, while O-vacancy centers were left in the oxide. This behavior was explained in terms of a model in which O diffused out of the oxide and into the Si; the driving force for this being the temperature-dependent solubility limit of O in Si. This mechanism was expected to be active in float-zone substrates at temperatures above 700C. In the case of high O-content Czochralski substrates, O-vacancy creation in the oxide was also found when annealing was performed at temperatures above about 1320C. At annealing temperatures of about 1000C, dissolved O interstitial diffusion into the Si/SiO2 interface, and the precipitation of SiO2 platelets in the bulk, were expected.

R.A.B.Devine: Journal de Physique III, 1996, 6[12], 1569-94