MOD法在LaAlO3单晶上沉积La0.4Sr0.6CoO3导电缓冲层

用金属有机物沉积(MOD)法在LaAlO3(100)单晶基底上制备了立方钙钛矿型导电缓冲层La0.4Sr0.6CoO3(LaSrCoO)薄膜。根据热分析曲线确定前驱膜的热处理工艺,其中前驱膜的热分解温度为620～800℃,涂膜的结晶温度为825℃。由X射线衍射(XRD)分析可知,热处理后涂膜的主相是LaSrCoO,其择优取向为<100>;另外还有La2CO5和LaCoO3等杂相。由φ扫描和(100)极图可知,所制备的涂膜有较强双轴织构。用标准四引线法测量了涂膜的室温和低温电阻率,在77K时达到1.04×10-4?·m,实现了沉积导电缓冲层的目的。

MOD Method Used for Conductive La0.4Sr0.6CoO3 Buffer Layers Deposition on LaAlO3 Single Crystal Substrates

Conductive La0.4Sr0.6CoO3 (LaSrCoO) buffer layers with cubic-perovskite structure were prepared on LaAlO3(100) single crystal substrates by the metal organic deposition (MOD) process. The heat-treatment process was designed according to the differential thermal analysis and thermogravimetric analysis, in which the thermolysis temperature of the precursor layer is 620-800 oC and the crystallization temperature of the buffer layer is 825 oC. According to X-ray diffraction (XRD) analysis, the main phase is LaSrCoO with <100> preferred orientation after heat treatment; in addition, impurity phases are La2CO5 and LaCoO3. The LaSrCoO buffer layers have the strong biaxial texture by φ-scan and (100) polar figure. The resistivity of the buffer layers was measured by standard four-probe DC method from room-temperature to liquid-N2 temperature, and the result show that its resistivity is 1.04×10-4 Ω·m at 77 K, achieving the purpose of conductive buffer layer deposition.