摘要
用磁控溅射方法在不同单晶衬底材料上制备了一系列含La2/3Ca1/3MnO3(LCMO)薄膜。当薄膜厚度大于200?,在我们实验条件下可观测到金属-绝缘体转变,且转变温度随厚度和衬底材料而变化。渗流电阻模型被用来解释薄膜材料的电输运特性,结合薄膜外延特性(晶格失配)和薄膜与衬底的相互作用,及薄膜表面、界面粗糙度的测量可知薄膜的剩余电阻、极化子的激活能、金属-绝缘体转变温度等密切与薄膜质量相关。
By off-set rf-magnetosputtering technique, we have fabricated La2/3Ca1/3MnO3 (LCMO) films on SrTiO3 ( STO ) , Yttrium stabilized ZrO2 ( YSZ ) and sapphire ( ALO ) substrates. A metal-insulator transition was observed for samples with the thickness is larger than 200?, the transition temperature, TMI varies with the substrate and the thickness of LCMO. A percolation model was used to fit the temperature dependence of resistance for all films. In combining with the epitaxial process, the interaction between the film and substrates, and the results for sur- face and interface roughness of the films, we argue that the surplus resistance of the films, the active energy of the polaron, and the metal-insulator transition temperature are strongly related to the quality of the films.
出处
《核技术》
CAS
CSCD
北大核心
2004年第5期329-333,共5页
Nuclear Techniques
基金
国家自然科学基金资助项目(No.10174030
90201039
10023001
001CB610602)
教育部博士点基金
