title: Fabrication of homogenous multilayered W films by multi-step sputtering deposition: a novel grain boundary enrichment strategy.
abstract: Using a multi-step deposition approach, we develop a strategy of homogeneous multilayered (HM) structure to enrich the grain boundary (GB) of sputtered W films. In comparison with the single-layered film, the HM W film is easily controllable for the film GB density. When decreasing the film modulation period t m from 160 nm to 7 nm, the GB density gradually increased from 0.065 nm(-1) to 0.275 nm(-1) without changing the phase structure of the films. Accordingly, the film's electrical resistivity and mechanical hardness, which are related to the GBs, changed from 40.1 μΩ · cm to 75.3 μΩ · cm and from 12.1 GPa to 16.2 GPa, respectively. Detailed analysis showed that the formation of an HM structure is related to the temperature evolution of the film growing surface during the multi-step sputtering process. This study could provide a general engineering approach to enrich film interfaces and allows for the development of thin films with novel microstructures.
authors.affiliation: Key Laboratory of Radiation Physics and Technology of Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, People's Republic of China.
authors.forename: Hailin
authors.initials: H
authors.lastname: Zhu
authors.forename: Jijun
authors.initials: J
authors.lastname: Yang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wan
authors.forename: Liwei
authors.initials: L
authors.lastname: Lin
authors.forename: Jiali
authors.initials: J
authors.lastname: Liao
authors.forename: Yuanyou
authors.initials: Y
authors.lastname: Yang
authors.forename: Ning
authors.initials: N
authors.lastname: Liu