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Updated: Jun 9, 2025
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The Effect of Anodization Parameters on the Aluminum Oxide Dielectric Layer of Thin-Film Transistors
Published on: May 24, 2020
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Aluminum Josephson junction microstructure and electrical properties modified by thermal annealing
Nikita D Korshakov1,2, Dmitry O Moskalev1,2, Anastasia A Soloveva1,2
1FMN Laboratory, Bauman Moscow State Technical University, Moscow, Russia, 105005.
Scientific Reports
|October 31, 2024
Summary
Post-fabrication thermal annealing improves Josephson junction reproducibility for superconducting quantum processors. This method enhances junction resistance and enables precise qubit frequency tuning, crucial for scalable quantum computing.
Area of Science:
- Quantum Computing
- Materials Science
- Superconductivity
Background:
- Reproducibility of Al/AlOx/Al Josephson junctions is critical for scaling superconducting quantum processors.
- Fabrication variations in Josephson junction microstructure and electrical properties cause transmon qubit frequency uncertainty.
Purpose of the Study:
- To present a post-fabrication thermal annealing process to enhance Josephson junction reproducibility.
- To enable scalable frequency trimming for fixed-frequency transmon qubits.
Main Methods:
- Utilized a thermal post-exposure annealing method on Al/AlOx/Al Josephson junctions.
- Investigated the temperature and time dependence of junction resistance.
- Analyzed the impact of electrode dimensions and sidewall contributions on resistance.
- Developed a theoretical model for tunnel barrier modification based on oxygen concentration gradients.
Main Results:
- Achieved a 175% increase in junction resistance.
- Demonstrated a 60% decrease in resistance with 10% steps (Rn).
- Observed strong temperature dependence and weak holding time dependence of resistance.
- Identified significant influence of electrode dimensions and sidewalls on post-annealing resistance.
Conclusions:
- The thermal annealing process offers a solution for stable and reproducible tunnel barriers.
- This method provides scalable frequency trimming for transmon qubits.
- The findings facilitate the advancement of superconducting quantum computing hardware.
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