The geometrical and electronic structures of a thin SiO2 film epitaxially grown on a Mo(112) substrate have been determined by first-principles density-functional theory calculations. beta-cristobalite, beta-tridymite, alpha-quartz, and beta-quartz phases were considered. The film grows initially with an OH-terminated beta-cristobalite structure which provides the strongest adhesion energy to the Mo substrate. High-temperature annealing results in a complete dehydroxylation and reconstruction of the top layer of the cristobalite film with the formation of two-membered silica rings. This accounts for a specific band at 795 cm(-1) observed in the Fourier transform infra-red (FTIR) spectrum of the annealed epilayer
Ricci, D., Pacchioni, G. (2004). Structure of ultrathin crystalline SiO2 films on Mo(112). PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS, 69(16), 161307-1-161307-4 [10.1103/PhysRevB.69.161307].
Structure of ultrathin crystalline SiO2 films on Mo(112)
PACCHIONI, GIANFRANCO
2004
Abstract
The geometrical and electronic structures of a thin SiO2 film epitaxially grown on a Mo(112) substrate have been determined by first-principles density-functional theory calculations. beta-cristobalite, beta-tridymite, alpha-quartz, and beta-quartz phases were considered. The film grows initially with an OH-terminated beta-cristobalite structure which provides the strongest adhesion energy to the Mo substrate. High-temperature annealing results in a complete dehydroxylation and reconstruction of the top layer of the cristobalite film with the formation of two-membered silica rings. This accounts for a specific band at 795 cm(-1) observed in the Fourier transform infra-red (FTIR) spectrum of the annealed epilayer
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