Journal article

Gate-dielectric stack engineering for high-mobility and low-noise SiMOS quantum devices

Md Mamunur Rahman, Ensar Vahapoglu, Kok Wai Chan, Tuomo Tanttu, Ajit Dash, Jonathan Yue Huang, Steve Yianni, Venkatesh Chenniappan, Jesús D Cifuentes, Fay E Hudson, Christopher C Escott, Yik Kheng Lee, Nard Dumoulin Stuyck, Arne Laucht, Andrea Morello, Andre Saraiva, Jared H Cole, Andrew S Dzurak, Wee Han Lim

npj Quantum Materials | Springer Science and Business Media LLC | Published : 2026

Open access

Abstract

We systematically investigate the interplay between materials engineering, quantum transport, and low-frequency charge noise in silicon metal-oxide-semiconductor (SiMOS) quantum devices. By combining Hall-bar transport measurements with charge-noise spectroscopy of gate-defined quantum dots, we identify correlations between gate-stack design, carrier mobility, and electrostatic noise, providing an experimental case study of material and process dependencies relevant to low-noise, high-mobility operation. Hall-bar studies show that varying the oxidant (H2O or D2O) during ALD Al2O3 growth has very little influence on mobility, whereas increasing the Al2O3 deposition temperature from 200 °C to ..

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University of Melbourne Researchers