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.
@article{arxiv.0808.2262,
title = {Modeling electrostatic and quantum detection of molecules},
author = {S. Vasudevan and K. Walczak and N. Kapur and M. Neurock and A. W. Ghosh},
journal= {arXiv preprint arXiv:0808.2262},
year = {2008}
}