Observation of a doping-dependent orientation effect of the depletion of silicon self-interstitials during oxidation

We conducted an experiment to study the growth kintetics of the oxidation-induced stacking faults (OSF) of n- and p-type (100) and (111) Si wafers with resistivities of 0.8-15 Ω cm. The OSF size data are as expected for the p-type (100) and (111) wafers as well as for the n-type (100) wafers. For the n-type (111) 0.8-2 Ω cm wafers, however, no OSF were generated at a temperature higher than ∼1100°C and those grown at 1050°C are considerably smaller than expected. This indicates that in the n-type (111) wafers there exists a mechanism that depletes Si self-interstitials, in addition to the normal mechanism of interstitial injection. Obviously, the effect is dependent on orientation as well as on doping. The same kind of effect was found before via diffusion studies, which, however, did not appear as doping dependent. We propose that this discrepancy is apparently due to the fact that, in one diffusion experiment, p+ (111) materials (Ga implanted to a concentration exceeding 1020 cm-3) were oxidized.

Duke Scholars

Author Teh Yu Tan Thomas Lord Department of Mechanical Engineering and Materia ...