残余应力对SrRuo3薄膜磁学及电输运性能的影响  

Effect of Residual Stress on Magnetic and Electrical Transport Properties in SrRuO_3 Thin Films

作　　者：朱明康[1,2] 董显林[2] 陈莹[2] 丁国际[1] 王根水[2] 

机构地区：[1]上海大学环境与化学工程学院,上海200436 [2]中国科学院上海硅酸盐研究所,上海200050

出　　处：《无机材料学报》2017年第1期75-80,共6页Journal of Inorganic Materials

基　　金：国家自然科学基金(61376086);国家重点基础研究发展计划(2012CB619406)~~

摘　　要：采用射频磁控溅射法在单晶SrTiO_3(STO)衬底和硅(Si)衬底上制备出不同取向的SrRuO_3(SRO)薄膜,对薄膜的残余应力进行了分析,并研究了应力对不同取向SRO薄膜磁学性能与电输运特性的影响。根据X射线衍射(XRD)结果分析可知,Si基SRO薄膜为多晶单轴取向薄膜,且应力来源主要为热失配拉应力;STO基SRO薄膜为外延薄膜,其应力主要为热失配压应力和外延压应力;磁学性能测试表明,(001)取向SRO薄膜比(110)取向薄膜拥有更高的居里温度TC;压应力提高了(001)取向SRO薄膜的TC,却降低了(110)取向薄膜的TC。电阻性能测试表明,对于在同种类型衬底上沉积的SRO薄膜,(001)取向的薄膜的剩余表面电阻比(RRR)高于(110)取向的薄膜。另外,拉应力引起了薄膜微结构的无序度增加,弱化了表面电阻率的温度依赖性,提高了金属绝缘体转变温度(TMI)。A series of SrRuO3 （SRO） thin films with preferential orientations were grown on SrTiO3 （STO） and Si substrates respectively by radio frequency （RF） magnetron sputtering technique. XRD results show that STO-based SRO thin films are epitaxial which differ from the one-axis orineted Si-based films. Residual stress type of the deposited films and effect of the stress on magnetic and electrical transport properties were systematically analyzed and summarized. STO-based SRO films suffer from compressive stress due to the lattice and thermal mismatch, while the Si-based films are subjected to tensile stress which is only derived from the thermal mismatch. The compressive stress promotes the Curie temperature （Tc） of （001）-oriented SRO films, but reduces the Tc of （110）-oriented SRO films, which may be due to the different states of rotation and tilt of RuO6 octahedron. Besides, the （001）-oriented SRO films possess higher Tc than the （110）-oriented SRO films all along. The results of temperature versus resistivity measurements reveal that residual resistivity ratio （RRR） of （001）-oriented SRO films is higher than that of （110）-oriented SRO films which deposited on the same substrate. Moreover, the temperature of metal-insulator transition （TMI） increases from 16 K to 32 K while the temperature dependence of resistivity is suppressed by the tensile stress.

关 键 词：钌酸锶 取向 残余应力 磁学性能 电输运特性 

分 类 号：TQ174[化学工程—陶瓷工业]