以光辅助MOCVD法在有取向Ni衬底及LAO单晶衬底上制备YBCO外延膜的比较研究

摘要

采用光辅助金属有机物化学气相沉积(MOCVD)法,在生长有CeO2/YSZ/Y2 O3(YSZ为Y稳定的ZrO2)缓冲层的双轴取向Ni衬底上进行了YBa2 Cu3 O7_x(YBCO)外延膜生长,并与LaAlO3(100)[LAO(100)]单晶衬底上的YBCO外延膜生长进行了对比.发现在Ni衬底上c轴取向YBCO外延膜的生长温度比LAO衬底上的生长温度低约30℃,但生长速度更快.经分析认为,这种差别主要是由于Ni衬底的热导率比LAO衬底高造成的.Ni衬底及LAO衬底上生长的c轴取向YBCO外延膜的超导极限电流密度(Jc)分别约为0.5 MA/cm2及1.8 MA/cm2.%A comparative study of YBa2Cu307-χ( YBCO) films grown on biaxially textured Ni substrates [using CeO2/YSZ/Y2O3(YSZ is Y stabilized ZrO2) as buffer layers] and LaA103( 100) [LAO( 100) ] substrates by photo-assisted metal organic chemical vapor deposition ( MOCVD) was carried out. It is found that the growing temperature of YBCO film grown on Ni substrate is lower about 30℃ than that on LAO substrate. Besides, the growth rate on Ni substrate is higher than that on LAO. The phenomena can be explained by the fact that the thermal conduction of Ni substrate is better than LAO. The critical superconducting current density Jc of YBCO films grown on Ni substrate and LAO substrate are about 0. 5 and 1. 8 MA/cm2, respectively.