Evolution of in situ growth stresses and interfacial structure in phase changing Cu/V multilayered thin films
Evolution of in situ growth stresses and interfacial structure in phase changing Cu/V multilayered thin films
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DOI：
10.1016/j.actamat.2018.01.023
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发表时间：
2018-04
期刊：
影响因子：
9.4
通讯作者：
Q. Guo;G. Thompson
中科院分区：
文献类型：
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作者：
Q. Guo;G. Thompson
随着 Cu/V 多层薄膜中层厚度的减小，Cu 会发生从面心立方 (fcc) 到体心立方 (bcc) 的相变。溅射沉积了一系列具有相等层厚、双层间距值从 40 nm 到 0.6 nm 的 Cu/V 多层薄膜，并在沉积过程中监测了它们的原位生长应力。当双层间距减小并且各层保持其体相稳定性时，多层膜中的拉伸应力减小。这导致界面处产生压缩应变，即使铜响应于应变而形成堆垛层错。当双层为 2nm 时，Cu 层相转变为 bcc，并采用与 bcc V 不同的自己的晶格参数。双层间距的进一步减小保留了结晶 bcc 相，但层之间具有匹配的晶格间距。尽管元素在块体状态下是不混溶的，但通过原子探针断层扫描对显着的混合进行了量化。相变还导致薄膜的整体拉伸生长应力增加。
As the layer thickness is reduced in a Cu/V multilayered thin film, a change in phase from face centered cubic (fcc)-to-body centered cubic (bcc) can result for Cu. A series of Cu/V multilayered films with equal layer thicknesses that spanned bilayer spacing values from 40 nm to 0.6 nm have been sputtered deposited with theirin situgrowth stress monitored during the deposition. When the bilayer spacing was reduced, and the layers maintained their bulk phase stability, the tensile stress in the multilayer film reduced. This has been contributed to compressive strain generated at the interfaces even with Cu forming stacking faults in response to the strain. When the bilayer was at 2 nm, the Cu layer phase transformed to bcc and adopted its own lattice parameter separate from that of bcc V. Further reductions in bilayer spacing retained a crystalline bcc phase but with a matching lattice spacing between the layers. Significant intermixing was quantified by atom probe tomography even though the elements are immiscible in the bulk state. The change in phase also resulted in an increase in the film's overall tensile growth stress.