Modeling electrostatic and quantum detection of molecules

S. Vasudevan; K. Walczak; N. Kapur; M. Neurock; A. W. Ghosh

doi:10.1109/jsen.2008.923264

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arXiv · 0808.2262

Modeling electrostatic and quantum detection of molecules

S. Vasudevan·K. Walczak·N. Kapur·M. Neurock·A. W. Ghosh

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Abstract

We describe two different modes for electronically detecting an adsorbed molecule using a nanoscale transistor. The attachment of an ionic molecular target shifts the threshold voltage through modulation of the depletion layer electrostatics. A stronger bonding between the molecule and the channel, involving actual overlap of their quantum mechanical wavefunctions, leads to scattering by the molecular traps that creates characteristic fingerprints when scanned with a backgate. We describe a theoretical approach to model these transport characteristics.

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S. Vasudevan, K. Walczak, N. Kapur, M. Neurock, A. W. Ghosh. 2008-08-18. Modeling electrostatic and quantum detection of molecules. https://doi.org/10.1109/jsen.2008.923264

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