Abstract The engineering of grain boundaries (GB) by controlled twin boundaries introduction in the copper matrix is a promising way to achieve higher strength coupled with sufficient ductility and conductivity of copper materials being in a high demand for modern electronics. In the work, the oversized Bi atoms were introduced in the copper film using two step direct current (DC) electrodeposition technique. Via XRD, SEM and EBSD techniques it was shown that the fraction of twinned boundaries and the orientation of Cu and (100-x)Cu-xBi (x=0.1, 0.5, 0.75 mol.%) films highly depend on the Bi(NiO3)3 concentration in the bath solution. Copper films possess both remarkably high hardness of 1.9±0.2 GPa and Elastic modulus of 67±7 GPa The 99.5Cu-0.5Bi (mol.%) film possesses the moderate hardness of 1±0.1 GPa and Elastic modulus of 94±9 GPa. Possible mechanisms of bismuth incorporation in the structure and its effect on mechanical properties of the copper based films are discussed.

中文翻译：

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直流电沉积双晶铜铋薄膜的微观结构和力学性能

摘要 通过在铜基体中引入受控孪晶界来设计晶界 (GB) 是一种有前途的方法，可以实现更高的强度，同时满足现代电子产品对铜材料的高需求。在这项工作中，使用两步直流 (DC) 电沉积技术将超大尺寸的 Bi 原子引入铜膜中。通过 XRD、SEM 和 EBSD 技术表明，孪晶边界的比例以及 Cu 和 (100-x)Cu-xBi (x=0.1, 0.5, 0.75 mol.%) 薄膜的取向高度依赖于 Bi(NiO3 )3 浴液中的浓度。铜膜同时具有 1.9±0.2 GPa 的极高硬度和 67±7 GPa 的弹性模量 99.5Cu-0.5Bi (mol.%) 膜具有 1±0.1 GPa 的中等硬度和 94±9 GPa 的弹性模量。