|About this Abstract
||2020 TMS Annual Meeting & Exhibition
||Solid State Diffusion Bonding of Metals and Alloys
||Anisotropic Grain Growth in Cu Joints at Low Temperatures by <111>-oriented Nanotwinned Copper Films
||Chang-Chih Hsieh, Chih Chen
|On-Site Speaker (Planned)
Grain growth in Cu joints can eliminate the bonding interface and ensure good bonding strength, and hence increase the reliabilities for the Cu-to-Cu joints, such as resistance to temperature cycling tests. However, grain growth takes place at temperature higher than 300 °C in regular Cu joints.
In this study, we reduce the temperature for grain growth of Cu joints at 225 °C using highly (111)-oriented nanotwinned Cu (nt-Cu) films. We electrodeposited nt-Cu films with periodic reverse waveform rather than DC waveform. Then We bonded two pieces of nt-Cu films at 225 °C under 114 psi(0.78MPa) for 120 min at 10-3 torr. The microstructure analysis indicates that extremely anisotropic grain growth can be triggered at this conditions. This temperature is the lowest one that has been reported for the elimination of the bonding interface of Cu-to-Cu joints.
||Planned: Supplemental Proceedings volume