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arXiv · 1009.2537

Lateral Confinement of Electrons in Vicinal N-polar AlGaN/GaN Heterostructure

Digbijoy N. Nath·Stacia Keller·Eric Hsieh·Steven P. DenBaars·Umesh K. Mishra·Siddharth Rajan
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Abstract

We studied orientation dependent transport in vicinal N-polar AlGaN/GaN heterostructures. We observed significant anisotropy in the current carrying charge parallel and perpendicular to the miscut direction. A quantitative estimate of the charge anisotropy was made based on gated TLM and Hall measurements. The formation of electro-statically confined one-dimensional channels is hypothesized to explain charge anisotropy. A mathematical model was used to verify that polarization charges distributed on miscut structure can create lateral one-dimensional confinement in vicinal substrates. This polarization-engineered electrostatic confinement observed is promising for new research on low-dimensional physics and devices besides providing a template for manufacturable one-dimensional devices.

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Digbijoy N. Nath, Stacia Keller, Eric Hsieh, Steven P. DenBaars, Umesh K. Mishra, Siddharth Rajan. 2010-09-13. Lateral Confinement of Electrons in Vicinal N-polar AlGaN/GaN Heterostructure. https://doi.org/10.1063/1.3505319

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