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

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.