Perovskite Thin Films

The unique combination of (a) highly brilliant x-rays produced in a modernthird generation synchrotron source (b) the availability of a fast single-photoncounting area pixel detector and (c) a pulsed laser deposition equipmentfor in-situ growth enables one to study both the structure and kinetics of thethin film growth of perovskites. The surface structure of titanium-dioxideterminatedstrontium titanate (STO) was analyzed by surface x-ray diffraction(SXRD) for two different environments: One (cold) at room temperature andin ultra-high vacuum and the other (hot) at elevated temperatures and in anoxygen background i.e. under conditions typical for perovskite thin filmgrowth. SXRD was used to determine the atomic structures of lanthanumstrontium manganate thin films grown monolayer-by-monolayer on STO bypulsed laser deposition. Structures were solved using the COBRA phase-retrievalmethod and subsequent structural refinement. These results allowedconcluding on the onset of colossal magnetoresistance. In-situ kinetic studiesof the thin film growth led to the proposition of a novel energeticsmoothing mechanism for the growth of complex metal-oxide thin films.