Overlapping-gate architecture for silicon Hall bar MOSFET devices in the low electron density regime

Laurens H. Willems van Beveren; Kuan Y. Tan; Nai-Shyan Lai; Andrew S. Dzurak; Alex R. Hamilton

doi:10.1063/1.3501136

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arXiv · 1009.3109

Overlapping-gate architecture for silicon Hall bar MOSFET devices in the low electron density regime

Laurens H. Willems van Beveren·Kuan Y. Tan·Nai-Shyan Lai·Andrew S. Dzurak·Alex R. Hamilton

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Abstract

We report the fabrication and study of Hall bar MOSFET devices in which an overlapping-gate architecture allows four-terminal measurements of low-density 2D electron systems, while maintaining a high density at the ohmic contacts. Comparison with devices made using a standard single gate show that measurements can be performed at much lower densities and higher channel resistances, despite a reduced peak mobility. We also observe a voltage threshold shift which we attribute to negative oxide charge, injected during electron-beam lithography processing.

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Laurens H. Willems van Beveren, Kuan Y. Tan, Nai-Shyan Lai, Andrew S. Dzurak, Alex R. Hamilton. 2010-09-16. Overlapping-gate architecture for silicon Hall bar MOSFET devices in the low electron density regime. https://doi.org/10.1063/1.3501136

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