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Title: Carrier Transport in Films of Alkyl-Ligand-Terminated Silicon Nanocrystals

Abstract

Silicon nanocrystals (Si NCs) have shown great promise for electroluminescent and photoluminescent applications. In order to optimize the properties of Si NC devices, however, electronic transport in Si NC films needs to be thoroughly understood. Here we present a systematic study of the temperature and electric field dependence of conductivity in films of alkyl-ligand-terminated Si NCs, which to date have shown the highest potential for device applications. Our measurements suggest that the conductivity is limited by the ionization of rare NCs containing donor impurities. At low bias, this ionization is thermally activated, with an ionization energy equal to twice the NC charging energy. As the bias is increased, the ionization energy is reduced by the electric field, as determined by the Poole-Frenkel effect. At large bias and sufficiently low temperature, we observe cold ionization of electrons from donor-containing NCs, with a characteristic tunneling length of about 1 nm. The temperature- and electric-field-dependent conductance measurements presented here provide a systematic and comprehensive picture for electron transport in lightly doped nanocrystal films.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1395119
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry. C; Journal Volume: 118; Journal Issue: 34
Country of Publication:
United States
Language:
English

Citation Formats

Chen, Ting, Skinner, Brian, Xie, Wei, Shklovskii, B. I., and Kortshagen, Uwe R. Carrier Transport in Films of Alkyl-Ligand-Terminated Silicon Nanocrystals. United States: N. p., 2014. Web. doi:10.1021/jp5051723.
Chen, Ting, Skinner, Brian, Xie, Wei, Shklovskii, B. I., & Kortshagen, Uwe R. Carrier Transport in Films of Alkyl-Ligand-Terminated Silicon Nanocrystals. United States. doi:10.1021/jp5051723.
Chen, Ting, Skinner, Brian, Xie, Wei, Shklovskii, B. I., and Kortshagen, Uwe R. Thu . "Carrier Transport in Films of Alkyl-Ligand-Terminated Silicon Nanocrystals". United States. doi:10.1021/jp5051723.
@article{osti_1395119,
title = {Carrier Transport in Films of Alkyl-Ligand-Terminated Silicon Nanocrystals},
author = {Chen, Ting and Skinner, Brian and Xie, Wei and Shklovskii, B. I. and Kortshagen, Uwe R.},
abstractNote = {Silicon nanocrystals (Si NCs) have shown great promise for electroluminescent and photoluminescent applications. In order to optimize the properties of Si NC devices, however, electronic transport in Si NC films needs to be thoroughly understood. Here we present a systematic study of the temperature and electric field dependence of conductivity in films of alkyl-ligand-terminated Si NCs, which to date have shown the highest potential for device applications. Our measurements suggest that the conductivity is limited by the ionization of rare NCs containing donor impurities. At low bias, this ionization is thermally activated, with an ionization energy equal to twice the NC charging energy. As the bias is increased, the ionization energy is reduced by the electric field, as determined by the Poole-Frenkel effect. At large bias and sufficiently low temperature, we observe cold ionization of electrons from donor-containing NCs, with a characteristic tunneling length of about 1 nm. The temperature- and electric-field-dependent conductance measurements presented here provide a systematic and comprehensive picture for electron transport in lightly doped nanocrystal films.},
doi = {10.1021/jp5051723},
journal = {Journal of Physical Chemistry. C},
number = 34,
volume = 118,
place = {United States},
year = {Thu Aug 28 00:00:00 EDT 2014},
month = {Thu Aug 28 00:00:00 EDT 2014}
}
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  • No abstract prepared.