Annealing characteristics of pulsed laser deposited homoepitaxial SrTiO3 thin films

The homoepitaxial growth of SrTiO3 (STO) films on as-polished STO(1 0 0) su bstrates by pulsed laser deposition has been exploited in detail. The intim ate correlation between the surface step edge density and reflection high-e nergy electron diffraction (RHEED) intensity is clearly demonstrated by mea suring the relation between the initial RHEED intensity drop and laser repe tition rates. Systematic in situ annealing schemes were performed to invest igate the film growth mechanisms. The results indicate that the two or thre e level growth May have occurred during some annealing schemes and can be i nterpreted by Stoyanov's step edge density model. Complementary atomic forc e microscopy investigations of the film surfaces further tend direct suppor t to the RHEED intensity observations. (C) 2001 Elsevier Science B.V. All r ights reserved.