用磁控溅射法制备含钼2.19%-35.15%(摩尔分数)的Cu-Mo合金薄膜,运用能谱仪(EDX)、X射线衍射仪(XRD)、透射电镜(TEM)、扫描电镜(SEM)、显微硬度仪和电阻计对薄膜成分、结构和性能进行研究。结果表明:Mo添加使Cu-Mo薄膜晶粒显著细化,Cu-Mo膜呈纳米晶结构,存在Mo在Cu中的FCC Cu(Mo)非平衡亚稳过饱和固溶体;随Mo含量的增加,Mo固溶度逐渐增加,而薄膜微晶体尺寸则逐渐减小,Mo的最大固溶度为30.6%。与纯Cu膜对比表明,Cu-Mo膜的显微硬度和电阻率随Mo含量的上升而持续增加。经200、400和650℃热处理1 h后,Cu-Mo膜的显微硬度和电阻率均降低,降幅与热处理温度呈正相关;经650℃退火后,Cu-Mo膜基体相晶粒长大,并出现亚微米-微米级富Cu第二相。在Cu-Mo膜的XRD谱中观察到Mo(110)特征峰,Cu-Mo薄膜结构和性能形成及演变的主要原因是添加Mo引起的晶粒细化效应以及热处理中基体相晶粒的生长。
The Cu-Mo alloy thin films with Mo content of 2.19%-35.15%(mole fraction) were prepared by magnetron sputtering.The compositions,structures and properties of thin films were investigated by EDX,XRD,TEM,SEM,microhardness instrument and resistivity meter.The results show that Mo addition refines the grain of Cu-Mo thin films significantly.Cu-Mo thin films possess nanocrystalline structure with the presence of FCC Cu(Mo) nonequilibrium metastable supersaturated solid solution,the Mo solubility gradually increases and the microcrystal size of thin films decreases comparatively with increasing Mo content,and the maximum Mo solubility is 30.6%.The comparison with pure Cu films reveals that both the microhardness and electrical resistivity of Cu-Mo thin films continuously increase with increasing Mo content.After heat-treated at 200,400 and 650 ℃ for 1 h,the microhardness and resistivity of Cu-Mo coating decrease.The descending range of the microhardness and resistivity are correlated positively with heat treatment temperature.Moreover,the grain of matrix phase grows continuously,and the appearance of submicron-micron Cu-rich second-phase in Cu-Mo films is found,the Mo(110) characteristic peak is observed in Cu-Mo films after annealed at 650 ℃.The formation and evolution of structures and properties of Cu-Mo thin films are mainly contributed to the grain refinement effect caused by Mo addition as well as the growth of matrix phase grain during annealing.