Deposition of CeO/sub 2/ buffer layers for YBCO coated conductors on biaxially textured Ni substrates by MOCVD technique

摘要

CeO/sub 2/ buffer layers for YBa/sub 2/Cu/sub 3/O/sub 7/(YBCO) coated conductors were deposited on biaxially textured Ni substrates by metalorganic chemical vapor deposition (MOCVD) method. The variables were the oxygen partial pressure (P/sub O2/), deposition temperature and time. The [200] texture of CeO/sub 2/ was formed at T = 500 /spl deg/C - 520 /spl deg/C, t = 3 - 15 min and P/sub O2/ = 2.30 torr, while the [111] and [200] texture were competitively formed at other condition. The surface roughness of CeO/sub 2/ films was as good as 5 - 15 nm up to 500 /spl deg/C, while it rapidly increased as a result of grain growth of the CeO/sub 2/ at T /spl ges/ 520 /spl deg/C. The surface roughness of the CeO/sub 2/ films also increased as the deposition time increased. The growth rate of the CeO/sub 2/ films at T = 520 /spl deg/C and P/sub O2/ = 2.30 torr was 200 nm/min, which is much higher than those prepared by other physical deposition methods.