大面积YBCO高温超导双面薄膜的生长研究

Growth of YBCO High-T_(c) Superconducting Thin Films on Two Sides of Substrates

采用倒筒式直流溅射 (ICS)方法 ,辐射方式加热基片 ,通过电机带动基片旋转 ,在两面同时溅射沉积YBCO高温超导双面薄膜。在加热温度为 85 0℃ ,总压强为 35Pa ,氧氩比为 1∶2 ,靶基距 5 0mm ,基片转速 5～ 40r/min条件下 ,在 2 0mm× 2 0mm的LaAlO3(10 0 )单晶基片上制得两面性能优良且一致性很好的YBCO高温超导双面薄膜。样品两面性能达到 :Tc0 =89 1K ,ΔTc=0 2K ,Jcl=2 6 9MA/cm2 ,Jc2 =2 74MA/m2 (77K ,0T) ,Rsl=0 2 4mΩ ,Rs2 =0 2 9mΩ(77K ,10GHz,0T) ,可满足制作微波器件的要求。

Double sided YBa 2Cu 3O 7 x high temperature superconducting thin films were simultaneously deposited on 20 mm×20 mm LaAlO 3 crystal substrates by rotating the substrate in a radiant heater.YBCO thin films were sputtered from single inverted cylindrical sputter gun.Under the optical parameters:substrate temperature 850 ℃,total gas pressure 35 Pa,O 2/Ar ratio 1∶2,the distance of 50 mm from target to substrate,substrate rotating rate of 5 r/min to 40 r/min,YBCO thin films with excellent superconducting properties were prepared, T c0 =89 1 K,Δ T c=0 2 K, J cl =2 69 MA/cm 2, J c2 =2 74 MA/cm 2(77 K,0 T), R sl =0 24 mΩ, R s2 =0 29 mΩ(77 K,10 GHz,0 T).The differences of the superconducting properties and the thickness of the YBCO thin films between the two sides are very small.These samples are good enough to fabricate microwave passive devices.