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arXiv · 2309.05219

Valley splitting by extended zone effective mass approximation incorporating strain in silicon

Jinichiro Noborisaka·Toshiaki Hayashi·Akira Fujiwara·Katsuhiko Nishiguchi
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Abstract

Silicon metal-oxide-semiconductor field effect transistors (MOSFETs) fabricated on a SIMOX (001) substrate, which is a kind of silicon on insulator (SOI) substrate, that is annealed at high temperature for a long time are known to exhibit large valley splitting, but the origin of this splitting has long been unknown. Extended zone effective-mass approximation (EMA) predicts that strain significantly affects valley splitting. In this study, we analyzed valley splitting based on this theory and found that the shear strain along <110> of approximately 5% near the buried oxide (BOX) interface is a promising source for large valley splitting.

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Jinichiro Noborisaka, Toshiaki Hayashi, Akira Fujiwara, Katsuhiko Nishiguchi. 2023-09-11. Valley splitting by extended zone effective mass approximation incorporating strain in silicon. https://doi.org/10.1063/5.0173578

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