{001｝LaAlO3衬底上沉积YBa2Cu3O7-x薄膜的HRXRD研究

摘要

采用脉冲激光沉积技术(PLD)在{001} LaAlO3(LAO)衬底上生长YBa2Cu3O7-x(YBCO)薄膜,并通过极图、摇摆曲线以及倒易空间图谱等高分辨X射线衍射技术(HRXRD)对其微结构进行表征.结果表明,YBCO薄膜的晶粒取向主要为{001}YBCO//{001}LAO,〈100〉YBCO//〈 100〉LAO,但还有2％的{001}YBCO//{001}LAO,〈 110〉YBCO//〈100〉LAO取向.摇摆曲线结果表明,YBCO的面外取向有一定的漫散(宽度为0.75°);薄膜面内存在90°±0.65° 〈110〉孪晶畴结构,主要是由四方到正交的相变过程中较大的局部应力以及<100〉和〈010〉方向应力差异引起的.%YBa2Cu3O7-x (YBCO) superconducting film was fabricated on {001 } LaAlO3 (LAO) substrate by pulse laser deposition (PLD),and its microstructure was examined by high resolution X-ray diffraction technology (HRXRD),such as pole figure,rocking curve,reciprocal space mapping.The results show that the YBCO crystalline alignment is almost {001}vaco//{001}LAO,〈100〉YBCO//〈100〉LAO besides 2％ {001 }YBco//{001 }LAo,〈110〉YBCO//〈100〉LAO.The out-plane alignment of YBCO is some spreading (the breadth is 0.75°).There are 90°+0.65°<110〉 twin domains in the film,which is caused by the high local stress and stress difference between 〈100〉 and 〈010〉 during the tetragonal to orthorhombic phase transition.