Lee Yun-Fong, Huang Yu-Chen, Chang Jui-Sheng, Cheng Ting-Yi, Chen Po-Yu, Huang Wei-Chieh, Lo Mei-Hsin, Fu Kuan-Lin, Lai Tse-Lin, Chang Po-Kai, Yu Zhong-Yen, Liu Cheng-Yi
Department of Chemical and Materials Engineering, National Central University, No. 300, Zhongda Road, Zhongli District, Taoyuan 32001, Taiwan.
R Soc Open Sci. 2024 Sep 11;11(9):240459. doi: 10.1098/rsos.240459. eCollection 2024 Sep.
Fine-grain copper (Cu) films (grain size: 100.36 nm) with a near-atomic-scale surface (0.39 nm) were electroplated. Without advanced post-surface treatment, Cu-Cu direct bonding can be achieved with present-day fine-grain Cu films at 130℃ in air ambient with a minimum pressure of 1 MPa. The instantaneous growth rate on the first day is 164.29 nm d. Also, the average growth rate (∆/∆) is evaluated by the present experimental results: (i) 218.185 nm d for the first-day period and (ii) 105.58 nm d during the first 14-day period. Ultrafast grain growth and near-atomic-scale surface facilitate grain boundary motion across the bonding interface, which is the key to achieve Cu-Cu direct bonding at 130℃ in air ambient.
电镀出了具有近原子尺度表面（0.39纳米）的细晶粒铜（Cu）薄膜（晶粒尺寸：100.36纳米）。在没有先进的表面后处理的情况下，当今的细晶粒铜薄膜在130℃的空气环境中，最低压力为1兆帕时，可以实现铜-铜直接键合。第一天的瞬时生长速率为164.29纳米/天。此外，根据目前的实验结果评估平均生长速率（∆/∆）：（i）第一天期间为218.185纳米/天，（ii）前14天期间为105.58纳米/天。超快的晶粒生长和近原子尺度的表面促进了晶界在键合界面上的移动，这是在130℃的空气环境中实现铜-铜直接键合的关键。
