物理学报2026，Vol.75Issue(11)：215-223,9.DOI:10.7498/aps.75.20260155
N2流速对外延TiN薄膜超导性质及维度特性的影响
Influences of N2 flow rate on the superconducting properties and dimensionality of epitaxial TiN thin films
摘要
Abstract
TiN thin films have received great attention in the field of superconducting quantum computing due to their low loss characteristics derived from stable chemical and thermal properties,as well as excellent electrical conductivity.In this study,TiN thin films with a thickness of 35 nm were epitaxially grown on MgO substrates using dc reactive magnetron sputtering technique.The crystal structure,film thickness,and surface morphology of the thin films were characterized using X-ray diffraction,X-ray reflection,and atomic force microscopy,respectively.The films exhibit a very flat surface with a root mean square roughness of only a few tenths of a nanometer.The influences of nitrogen(N2)flow rate on the surface morphology,superconducting transition temperature(Tc),residual resistivity ratio(RRR),normal-state resistivity(ρn),upper critical field,and superconducting dimensionality were investigated systematically.The experimental results show that TiN film deposited with a N2 flow rate of 1.5 sccm exhibits optimal performance,including the highest Tc(4.93 K),the largest RRR,the lowest ρn,and the lowest slope of the out-of-film upper critical field near Tc.Moreover,it is found that the background vacuum inside the growth chamber has a significant impact on the superconducting properties of TiN films,and the degradation of vacuum degree can lead to the decrease of Tc.The upper critical field reveals a significant anisotropic feature.Importantly,the in-film upper critical field data demonstrates that the optimization of sample quality leads to deviation from two-dimensional superconducting behavior,which provides a new perspective on the influencing factors of superconducting dimensionality beyond the thickness of films.The present results provide useful references for a comprehensive understanding of the relationship between growth parameters and the superconducting properties of thin films.关键词
TiN薄膜/超导电性/上临界场/维度Key words
TiN film/superconductivity/upper critical field/dimensionality引用本文复制引用
陈轼龙,刘钰川,孙宜辉,王小妮,彭炜,吴禹,牟刚,林志荣..N2流速对外延TiN薄膜超导性质及维度特性的影响[J].物理学报,2026,75(11):215-223,9.基金项目
中国科学院战略性先导科技专项(批准号:XDA0520202,XDB0670000)、国家重点研究发展计划(批准号:2023YFB4404904)、广东省重点领域研发计划(批准号:2020B0303030002)和集成电路材料全国重点实验室自主部署项目(批准号:SKLJC-Z2024-B04)资助的课题. Project supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDA0520202,XDB0670000),the National Key Research and Development Program of China(Grant No.2023YFB4404904),the Key-Area Research and Development Program of Guangdong Province,China(Grant No.2020B0303030002),and the Autonomous Deployment Project of State Key Laboratory of Materials for Integrated Circuits,China(Grant No.SKLJC-Z2024-B04). （批准号:XDA0520202,XDB0670000）
