Passivating Interfacial Pore Defects with Light Atoms To Enhance Heat Transport Across Cu/a-SiO₂ Interfaces.

Area of Science:

• Materials Science
• Nanotechnology
• Thermal Engineering

Background:

• Interconnect pitches in 3D integrated circuits are shrinking to submicrometer scales.
• Interfacial thermal conductance (ITC) across Cu/a-SiO2 hybrid-bonded interfaces is a critical heat-dissipation bottleneck.
• Nanoscale pores and light-atom incorporation complicate interfacial heat transport, but their combined influence is not well understood.

Purpose of the Study:

• To elucidate how pores and light atoms jointly regulate ITC in Cu/a-SiO2 hybrid-bonded interfaces.
• To establish a unified vibrational framework for pore-light-atom interactions.
• To provide process-compatible guidance for thermal management in ultrafine-pitch hybrid bonding.

Main Methods:

• Two-temperature-model molecular dynamics simulations.
• Utilized realistic interatomic potentials.
• Investigated the effects of pores on the Cu and a-SiO2 sides, and the influence of light-atom incorporation.

Main Results:

• Pores on the Cu side significantly suppress mid-frequency phonons and reduce ITC.
• Pores on the a-SiO2 side have a weaker effect on ITC.
• Light-atom incorporation leads to nonmonotonic ITC dependence, influenced by competing pore-induced surface states and spectral reshaping.

Conclusions:

• Pore-induced surface states disrupt phonon pathways, while light atoms can reshape spectra to enhance heat transport.
• A unified vibrational framework for pore-light-atom interactions was established.
• Findings offer guidance for thermal management in advanced 3D integrated circuits with hybrid bonding.