Surface resistance and morphology of YBCO films as a function of thickness
Surface resistance and morphology of YBCO films as a function of thickness
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YBCO 薄膜的表面电阻和形貌随厚度的变化
DOI：
10.1109/77.620961
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发表时间：
1997
影响因子：
1.8
通讯作者：
J. Krupka
中科院分区：
文献类型：
--
作者：
F.J.B. Stork;K. A. Beall;A. Roshko;D. DeGroot;D. Rudman;R. Ono;J. Krupka
研究了激光烧蚀YBa/sub 2/Cu/sub 3/O/sub 7-x/薄膜的生长形貌和表面电阻R/sub s/与厚度的关系，其转变温度超过89 K，临界电流密度在76 K时大于10/sup 6/ A/cm/sup 2/。厚度从50至1600 nm变化，而所有其他沉积条件保持恒定。用扫描电子显微镜和扫描隧道显微镜对薄膜的微观结构进行了表征，薄膜的厚度与薄膜的厚度呈指数为-0.5的幂律关系。用介质棒谐振器在76 K下测量表面电阻。对于小于300 nm厚的膜，场穿透的超导膜，引起的表观R/子S/的迅速增加，随着膜厚度的减小。厚度大于800 nm的薄膜出现微裂纹，R/sub s/急剧增加，在1000 nm以上没有观察到共振。
We have examined the thickness dependence of the growth morphology and surface resistance R/sub s/ of laser ablated YBa/sub 2/Cu/sub 3/O/sub 7-x/ films with transition temperatures over 89 K and critical current densities greater than 10/sup 6/ A/cm/sup 2/ at 76 K. The thickness was varied from 50 to 1600 nm while all other deposition conditions were maintained constant. The microstructure has been characterized by scanning electron microscopy and scanning tunneling microscopy continuously decreased with film thickness as a power law with an exponent of -0.5. The surface resistance was measured at 76 K with a dielectric rod resonator. For films less than 300 nm thick, the fields penetrated the superconducting films, causing a rapid increase in the apparent R/sub s/ with decreasing film thickness. Films thicker than 800 nm showed microcracks and the R/sub s/ increased sharply, and no resonance was observed above 1000 nm.