窄流道式MOCVD制备YGBCO超导层研究

Synthesis of YGBCO Superconducting Coatings by Metal Organic Chemical Vapor Deposition in Narrow Rectangular-Wedge Reactor

金属有机化学气相沉积能连续、快速的沉积高温超导带材YBa2Cu3O7-x(YBCO)超导层。但金属有机源的利用率与薄膜沉积速率以及沉积一致性难以兼顾,制备YBCO高温超导带材的成本居高不下。本文提出了一种新的窄流道式反应室以改进薄膜沉积的一致性。在200 mm长度腔体中沉积的280 nm厚的Y0.5Gd0.5Ba2Cu3O7-x薄膜Jc分布在3.2~3.5 MA/cm2(77 K,0 T),面外、面内半高宽值分别在1.39°~1.49°和1.88°~2.13°,表面平整致密。YBCO薄膜良好的一致性表明该窄流道反应室对制备YBa2Cu3O7-x超导带材有好的实用性。

The Y0.5 Gd0.5 Ba2Cu3O7_x(YGBCO)superconducting coatings were synthesized by metal organic chemical vapor deposition(MOCVD)in a lab-built reactor with a narrow rectangular wedge deposition zone,compri sing two tilted Cu-plates(300 mm×11 mm)inside the rectangular vacuum chamber to accelerate the velocity of metal organic vapor.The influence of the rectangular wedge reactor on the properties of the YGBCO coatings was in vestigated with X-ray diffraction,energy dispersive spectroscopy,scanning electron microscopy and critical current density(Jc)measurement.The results show that the rectangular wedge reactor had a major impact.To be specific,the compact,fairly uniform and single Y123-phased YGBCO coatings,280 nm in thickness and grown in a 200 mm long reactor,had a Jc up to 3.5 MA/cm^2(measured at 77 K and 0 T).We suggest that the marrow rectangular wedge reactor be capable of rapidly and continuously growing high quality YBCO superconducting tape by MOCVD.