Intrinsic origin of negative fixed charge in wet oxidation for silicon carbide
Y Ebihara, K Chokawa, S Kato, K Kamiya… - Applied Physics …, 2012 - pubs.aip.org
We demonstrate on the basis of first-principles calculations that the formation of carbonate-
like moiety in SiO 2 could be the intrinsic origin of negative fixed charge in SiC thermal
oxidation. We find that two possible origins for the negative fixed charges are O-lone-pair
state and a negatively charged CO 3 ion in SiO 2. Such CO 3 ion is able to be formed as a
result of the existence of residual C atoms in SiO 2, which are expected to be emitted from
the interface between SiC and SiO 2, and the incorporation of H atoms during wet oxidation.
like moiety in SiO 2 could be the intrinsic origin of negative fixed charge in SiC thermal
oxidation. We find that two possible origins for the negative fixed charges are O-lone-pair
state and a negatively charged CO 3 ion in SiO 2. Such CO 3 ion is able to be formed as a
result of the existence of residual C atoms in SiO 2, which are expected to be emitted from
the interface between SiC and SiO 2, and the incorporation of H atoms during wet oxidation.
