Oxygen Impurity-Tuned Structure and Adhesion Properties of the Cu/SiO2 Interface
Mengdie Lan1, Gaosheng Yan1, Wenshan Yu1
1State Key Laboratory for Strength and Vibration of Mechanical Structures, Shaanxi Engineering Laboratory for Vibration Control of Aerospace Structures, School of Aerospace Engineering, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
ACS Applied Materials & Interfaces
|April 20, 2024
Summary
Oxygen impurities degrade Cu/SiO2 interface strength by disrupting bonds. Introducing oxygen at interstitial sites enhances interface strength and adhesion, improving material performance in harsh environments.
Area of Science:
- Materials Science
- Surface Science
- Computational Materials Science
Background:
- Cu/SiO2 interface properties degrade in atmospheric environments, limiting engineering applications.
- Interfacial oxidation by oxygen impurities can disorder the structure and weaken the interface.
Purpose of the Study:
- Investigate the impact of oxygen impurities on Cu/SiO2 interface mechanical behavior.
- Explore methods to enhance the bonding properties and adhesion of the Cu/SiO2 interface.
Main Methods:
- Reactive molecular dynamics simulations were employed.
- Analysis of interfacial structure, bonding, and mechanical properties under oxygen interaction.
Main Results:
- Oxygen penetration disorders the interface, reducing tensile and shear strengths by disrupting Cu-O-Si bonds.
- Introducing oxygen at Cu interstitial sites forms O-Cu-O bonds, significantly enhancing interface strength and retaining structure.
- Interfacial oxidation shifts failure sites from within the oxide to the oxide-Cu interface.
Conclusions:
- Oxygen impurities have a dual effect on Cu/SiO2 interfaces, degrading properties at high concentrations but enhancing them when strategically introduced.
- Optimizing oxygen impurity placement is crucial for improving the adhesion and mechanical stability of metal/oxide interfaces.
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