Formation of Strain-Induced Quantum Dots in Gated Semiconductor Nanostructures

Ted Thorbeck; Neil M. Zimmerman

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arXiv · 1409.3549

Formation of Strain-Induced Quantum Dots in Gated Semiconductor Nanostructures

Ted Thorbeck·Neil M. Zimmerman

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Abstract

Elastic strain changes the energies of the conduction band in a semiconductor, which will affect transport through a semiconductor nanostructure. We show that the typical strains in a semiconductor nanostructure from metal gates are large enough to create strain-induced quantum dots (QDs). We simulate a commonly used QD device architecture, metal gates on bulk silicon, and show the formation of strain-induced QDs. The strain-induced QD can be eliminated by replacing the metal gates with poly-silicon gates. Thus strain can be as important as electrostatics to QD device operation operation.

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Ted Thorbeck, Neil M. Zimmerman. 2014-09-11. Formation of Strain-Induced Quantum Dots in Gated Semiconductor Nanostructures. https://arxiv.org/abs/1409.3549

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