Physical properties of superconducting Nb films

• Main Authors: Cheng, Yuan-Chen, 鄭原真
• Other Authors: Wu Maw-Kuen
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/02563995625734354301

碩士 === 國立清華大學 === 物理學系 === 85 === We have carried out a systematic study on the effect of film thickness to the physical properties of superconducting Nb thin films prepared by sputtering technique. We observed that several properties such as the residual conductivity, superconducting transition temperature TC, upper critical field HC2, I-V characteristics, and the effective coherence length, are characteristically different for films thicker or thinner than 80 nm. Detailed analysis of the data suggest that the observed behavior are related to the dimensional crossover of the studied films. The characteristic of the films that is thicker than 80 nmis 3-dimensional, while those with thickness less than 80nm behave more like 2-dimensional system.