Nanoscale field effect transistor for biomolecular signal amplification

Yu Chen; Xihua Wang; Mi K. Hong; Shyamsunder Erramilli; Carol Rosenberg; Pritiraj Mohanty

doi:10.1063/1.2822445

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arXiv · 0802.1756

Nanoscale field effect transistor for biomolecular signal amplification

Yu Chen·Xihua Wang·Mi K. Hong·Shyamsunder Erramilli·Carol Rosenberg·Pritiraj Mohanty

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Abstract

We report amplification of biomolecular recognition signal in lithographically defined silicon nanochannel devices. The devices are configured as field effect transistors (FET) in the reversed source-drain bias region. The measurement of the differential conductance of the nanowire channels in the FET allows sensitive detection of changes in the surface potential due to biomolecular binding. Narrower silicon channels demonstrate higher sensitivity to binding due to increased surface-to-volume ratio. The operation of the device in the negative source-drain region demonstrates signal amplification. The equivalence between protein binding and change in the surface potential is described.

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Yu Chen, Xihua Wang, Mi K. Hong, Shyamsunder Erramilli, Carol Rosenberg, Pritiraj Mohanty. 2008-02-13. Nanoscale field effect transistor for biomolecular signal amplification. https://doi.org/10.1063/1.2822445

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