Electric field thermopower modulation analysis of an interfacial conducting layer formed between Y_(2)O_(3) and rutile TiO_(2)

摘要

Electric field modulation analysis of thermopower (S)-carrier concentration (n) relation of a bilayer laminate structure composed of a 1.5-nm-thick conducting layer, probably Ti_(n)O_(2n-1) (n velence 2, 3, ...) Magneli phase, and rutile TiO_(2), was performed. The results clearly showed that both the rutile TiO_(2) and the thin interfacial layer contribute to carrier transport: the rutile TiO_(2) bulk region (mobility mu approx 0.03 cm~(2) V~(-1) s~(-1)) and the 1.5-nm-thick interfacial layer (mu approx 0.3 cm~(2) V~(-1) s~(-1)). The effective thickness of the interfacial layer, which was obtained from the S-n relation, was below approx3 nm, which agrees well with that of the TEM observation (approx1.5 nm), clearly showing that electric field modulation measurement of S-n relation can effectively clarify the carrier transport properties of a bilayer laminate structure.