Preparing Ultrathin MgB2 Thin Film by Ex-situ Annealing of Mg-B Precursor Film
Ultrathin MgB2 film is essential for the fabrication of MgB2 superconducting single photon detectors (SSPDs).In this paper,we prepared 20nm and 10nm MgB2 film using ex-situ annealing of Mg-B multilayer method.The precursor films were prepared by electron beam evaporation.A flowing Mg vapour and H2 was introduced in the annealing process to keep MgB2 thin film thermodynamically stable.The annealing temperature was between 680℃ and 740℃ and annealing time was 1-10min.20nm MgB2 films on MgO(111) substrates had the critical temperature (Tc) of 32.2K.The films grew along c-axes direction.As the substrate changed to SiC(001) and Al2O3(001),Tc decreased to 30.3K and 10.2K respectively.For 10nm MgB2 film on SiC(001) substrate,Tc was 24.2K.The self-field critical current density for 10nm and 20nm film on SiC(001) substrate was 2.1×106A/cm2 and 2.3×106A/cm2,respectively.AFM image showed that the film had a flat surface with mean roughness of 0.899nm for 10nm MgB2 film.
MgB2 Superconducting film Ultrathin film
Qian Dai Ruorun Ma Qingrong Feng Huai Zhang Qianqian Yang Ruijuan Nie Furen Wang
School of Physics, State Key Laboratory for Artificial Microstructures and Mesoscopic Physics,Peking University, Beijing 100871, China
国际会议
the Chinese Materials Congress 2012(2012年中国材料大会(CMC2012))
太原
英文
249-254
2012-07-13（万方平台首次上网日期，不代表论文的发表时间）