Grain boundary motions of low temperature and low pressure copper to copper direct bonding by electroplating ultra-fine-grain (UFG) Cu
Year: 2025
Type: article
Abstract: Cu-Cu direct bonding using electroplated ultrafine-grain Cu (107.24 nm) was studied in air at 110-150 °C. Unstable grain boundaries enabled ultrafast grain growth across the bonding interface, analyzed via coincidence site lattice (CSL) boundaries using EBSD. Above 125 °C, the Σ3 boundary length exceeded 40%, while below 120 °C it rapidly declined, transforming into Σ27a, indicating a critical transition dominated by the {115} plane. A temperature-time-dependent grain growth model was developed, incorporating CSL effects. Simulations showed grain evolution and timing of CSL boundary formation, with transition times from 316 to 190 s as temperature increased.
Source: Scientific Reports
Authors: Yun-Fong Lee, Chih-Wen Chiu, Chin-Yen Chiu, Yu-Chen Huang, Mei-Hsin Lo, Liu-Hsin-Chen Yang, Ting-Yi Cheng, Zhong-Yen Yu, Chih-En Hsu, Kai-Chi Lin, Po-Yu Chen, Wei-Cheih Huang, Jui-Sheng Chang, Shao-An Pan, Yi-Cheng Su, Chin-Li Lin, Hang-Chen Hsieh, Chia-Hua Lin, Cheng-Yi Liu
Institutions: National Central University, Tunghai University
Language: English
Topic: 3D IC and TSV technologies
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,690
OpenAlex ID: W4413420868