Growth kinetics of homoepitaxial strontium titanate films by interrupted pulsed laser deposition

The effects of the initial surface state on the evolution kinetics of the s urface morphology of strontium titanate (STO) films was investigated by in- situ monitoring the intensity variations of reflection high-energy electron diffraction (RHEED). In order to create various surface states prior to su bsequent depositions, we intentionally interrupted the pulsed laser deposit ion (PLD) at various points during the whole deposition course to perform i n-situ annealing over various periods of time. The depth of the initial dro p of RHEED intensity, which is a direct indication of changes in surface st ep densities, shows two distinct time scales. The results suggest that the evolution of a growing surface, and hence the ultimate film surface morphol ogy, may be manipulated by controlling the number density of the as-deposit ed growing islands through interrupted annealing.