Influence of Electron-Beam Annealing Duration on MgB₂ Film Superconductivity

Abstract:

A novel method to fabricate Magnesium diboride ( MgB₂) film by electron beam annealing was presented. The MgB₂ thin films could be prepared in a second or sub-second without any toxic diborane gas, extra Mg vapor or argon gas. The method has the advantages of short formation time and high efficiency. Based on this, the relationship between MgB₂ conductivity and electron beam annealing duration was investigated experimentally with an accelerating voltage of 40 × 10³ V, a beam current of 3×10³ A and different annealing durations of 0.1796s, 1860s, 0.2108s, 0.2200s and 0.2332s. The experimental results showed the MgB₂ film with 0.2200s has the highest T_c^onset , the most dense structure and the strongest diamagnetic signal. Its zero-field Jc at 5 K was 5.0 × 10⁶ A/cm². Also the variation of the film superconducting properties with the annealing duration was found, it will provide an important reference for the preparation of high-quality MgB₂ thin films.

• Periodical: Materials Science Forum (Volumes 745-746)
• Pages: 255-260
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.745-746.255
• Online since: February 2013
• Authors: Xiang Dong Kong, Qian Dai, Han Li, Qing Rong Feng, Ming Zhang Chu, Hong Xue, Jian Guo Li, Fu Ren Wang
• Keywords: Electron Beam Annealing, MgB₂, SiC Substrate, Superconducting Thin Film

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