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Growth mode control of the free carrier density in SrTiO3-d films

Akira Ohtomo·Harold Y. Hwang
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Abstract

We have studied the growth dynamics and electronic properties of SrTiO3-d homoepitaxial films by pulsed laser deposition. We find the two dominant factors determining the growth mode are the kinetics of surface crystallization and oxidation. When matched, persistent two-dimensional layer-by-layer growth can be obtained for hundreds of unit cells. By tuning these kinetic factors, oxygen vacancies can be frozen in the film, allowing controlled, systematic doping across a metal-insulator transition. Metallic films can be grown, exhibiting Hall mobilities as high as 25,000 cm2/Vs.

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Akira Ohtomo, Harold Y. Hwang. 2006-04-05. Growth mode control of the free carrier density in SrTiO3-d films. https://doi.org/10.1063/1.2798385

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