주제: Enhanced Thermodynamic Stability of Epitaxial Oxide Thin Films
연사: 송종현 교수 (충남대학교)
일시: 2007년 4월 23일 (월) 오후 4시
장소: 서울대학교 공대 Cyber 강의실 (37동 201-1호)
내용: Oxide thin films have been attracting much attention due to their exotic physical properties ranging from insulator to superconductor and possibility of device applications1. Here we reexamine the growth phase diagram of La0.7Sr0.3MnO3 thin films grown by pulsed laser deposition, which are heavily studied for their magnetoresistive properties even at room temperature. Unlike previous reports, we obtained stoichiometric films as grown, despite extremely reducing growth conditions, with bulk-like Curie temperatures exceeding 360oC. Masking this stability is a particularly strong dependence of film stoichiometry on the laser profile at the target and also on kinetics of ablated species on the substrate surface. These results indicate that bulk thermodynamic limitations can be overcome in perovskite films using epitaxial stabilization.
문 의 : 김상국 교수 (880-5854)