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arXiv · 1302.2264

Extrinsic and Intrinsic Photoresponse in Monodisperse Carbon Nanotube Thin Film Transistors

Erik Sczygelski·Vinod K. Sangwan·Chung-Chiang Wu·Heather N. Arnold·Ken Everaerts·Tobin J. Marks·Mark C. Hersam·Lincoln J. Lauhon
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Abstract

Spectroscopic, time-resolved scanning photocurrent microscopy is shown to distinguish the intrinsic photoresponse of monodisperse semiconducting (99%) single-walled carbon nanotubes (SWCNTs) from the extrinsic photoresponse of the substrate. A persistent positive photocurrent induced by near-IR excitation is attributed to the generation of free carriers by inter-band excitation in SWCNTs. For shorter excitation wavelengths, absorption by the Si substrate generates two types of photocurrent: a transient positive photoresponse, identified as a displacement current, and a persistent negative photocurrent that arises from photogating of the SWCNT thin film.

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Erik Sczygelski, Vinod K. Sangwan, Chung-Chiang Wu, Heather N. Arnold, Ken Everaerts, Tobin J. Marks, Mark C. Hersam, Lincoln J. Lauhon. 2013-02-09. Extrinsic and Intrinsic Photoresponse in Monodisperse Carbon Nanotube Thin Film Transistors. https://doi.org/10.1063/1.4793519

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