TU Darmstadt / ULB / TUbiblio

Spatially Resolved Electrostatic Potential and Photocurrent Generation in Carbon Nanotube Array Devices

Engel, Michael and Steiner, Mathias and Sundaram, Ravi S. and Krupke, Ralph and Green, Alexander A. and Hersam, Mark C. and Avouris, Phaedon (2012):
Spatially Resolved Electrostatic Potential and Photocurrent Generation in Carbon Nanotube Array Devices.
In: ACS Nano, p. 120713100926001, ISSN 1936-0851, [Online-Edition: http://dx.doi.org/10.1021/nn302416e],
[Article]

Abstract

We have used laser-excited photocurrent microscopy to map the internal electrostatic potential profile of semiconducting single-walled carbon nanotube (S-SWCNT) array devices with a spatial resolution of 250 nm. The measurements of S-SWCNTs on optically transparent samples provide new insights into the physical principles of device operation and reveal performance-limiting local heterogeneities in the electrostatic potential profile not observable with other imaging techniques. The experiments deliver photocurrent images from the underside of the S-SWCNT–metal contacts and thus enable the direct measurement of the charge carrier transfer lengths at the palladium–S-SWCNT and aluminum–S-SWCNT interfaces. We use the experimental results to formulate design rules for optimized layouts of S-SWCNT-based photovoltaic devices. Furthermore, we demonstrate the external control of the electrostatic potential profile in S-SWCNT array devices equipped with local metal gates.

Item Type: Article
Erschienen: 2012
Creators: Engel, Michael and Steiner, Mathias and Sundaram, Ravi S. and Krupke, Ralph and Green, Alexander A. and Hersam, Mark C. and Avouris, Phaedon
Title: Spatially Resolved Electrostatic Potential and Photocurrent Generation in Carbon Nanotube Array Devices
Language: English
Abstract:

We have used laser-excited photocurrent microscopy to map the internal electrostatic potential profile of semiconducting single-walled carbon nanotube (S-SWCNT) array devices with a spatial resolution of 250 nm. The measurements of S-SWCNTs on optically transparent samples provide new insights into the physical principles of device operation and reveal performance-limiting local heterogeneities in the electrostatic potential profile not observable with other imaging techniques. The experiments deliver photocurrent images from the underside of the S-SWCNT–metal contacts and thus enable the direct measurement of the charge carrier transfer lengths at the palladium–S-SWCNT and aluminum–S-SWCNT interfaces. We use the experimental results to formulate design rules for optimized layouts of S-SWCNT-based photovoltaic devices. Furthermore, we demonstrate the external control of the electrostatic potential profile in S-SWCNT array devices equipped with local metal gates.

Journal or Publication Title: ACS Nano
Uncontrolled Keywords: nanoelectronics; nano-optics; self-assembly
Divisions: 11 Department of Materials and Earth Sciences > Material Science > Fachgebiet Molekulare Nanostrukturen
11 Department of Materials and Earth Sciences > Material Science
11 Department of Materials and Earth Sciences
Date Deposited: 16 Aug 2012 07:01
Official URL: http://dx.doi.org/10.1021/nn302416e
Identification Number: doi:10.1021/nn302416e
Export:

Optionen (nur für Redakteure)

View Item View Item