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Title: Charge neutrality in heavily doped emitters

Abstract

The applicability of the quasineutrality approximation to modern emitters of solar cells is analytically reviewed. It is shown that this approximation is fulfilled in more than 80% of the depth of a typical solar-cell emitter, being particularly excellent in the heavily doped regions beneath the surface where most of the heavy doping effects arise. Our conclusions are in conflict with Redfield's recent affirmations.

Authors:
Publication Date:
Research Org.:
Instituto de Energia Solar ETSI Telecomunicacion Ciudad Universitaria Madrid-3, Spain
OSTI Identifier:
6299149
Resource Type:
Journal Article
Resource Relation:
Journal Name: Appl. Phys. Lett.; (United States); Journal Volume: 39:5
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; SOLAR CELLS; DOPED MATERIALS; MATHEMATICAL MODELS; COMPARATIVE EVALUATIONS; SPATIAL DISTRIBUTION; SURFACES; THEORETICAL DATA; DATA; DIRECT ENERGY CONVERTERS; DISTRIBUTION; EQUIPMENT; INFORMATION; MATERIALS; NUMERICAL DATA; PHOTOELECTRIC CELLS; PHOTOVOLTAIC CELLS; SOLAR EQUIPMENT 140501* -- Solar Energy Conversion-- Photovoltaic Conversion

Citation Formats

del Alamo, J.A.. Charge neutrality in heavily doped emitters. United States: N. p., 1981. Web. doi:10.1063/1.92764.
del Alamo, J.A.. Charge neutrality in heavily doped emitters. United States. doi:10.1063/1.92764.
del Alamo, J.A.. 1981. "Charge neutrality in heavily doped emitters". United States. doi:10.1063/1.92764.
@article{osti_6299149,
title = {Charge neutrality in heavily doped emitters},
author = {del Alamo, J.A.},
abstractNote = {The applicability of the quasineutrality approximation to modern emitters of solar cells is analytically reviewed. It is shown that this approximation is fulfilled in more than 80% of the depth of a typical solar-cell emitter, being particularly excellent in the heavily doped regions beneath the surface where most of the heavy doping effects arise. Our conclusions are in conflict with Redfield's recent affirmations.},
doi = {10.1063/1.92764},
journal = {Appl. Phys. Lett.; (United States)},
number = ,
volume = 39:5,
place = {United States},
year = 1981,
month = 9
}
  • Colloidal nanocrystals (NCs) of lead chalcogenides are a promising class of tunable infrared materials for applications in devices such as photodetectors and solar cells. Such devices typically employ electronic materials in which charge carrier concentrations are manipulated through “doping;” however, persistent electronic doping of these NCs remains a challenge. In this paper, we demonstrate that heavily doped n-type PbSe and PbS NCs can be realized utilizing ground-state electron transfer from cobaltocene. This allows injecting up to eight electrons per NC into the band-edge state and maintaining the doping level for at least a month at room temperature. Doping is confirmedmore » by inter- and intra-band optical absorption, as well as by carrier dynamics. In conclusion, FET measurements of doped NC films and the demonstration of a p-n diode provide additional evidence that the developed doping procedure allows for persistent incorporation of electrons into the quantum-confined NC states.« less
  • Colloidal nanocrystals (NCs) of lead chalcogenides are a promising class of tunable infrared materials for applications in devices such as photodetectors and solar cells. Such devices typically employ electronic materials in which charge carrier concentrations are manipulated through “doping;” however, persistent electronic doping of these NCs remains a challenge. Here, we demonstrate that heavily doped n-type PbSe and PbS NCs can be realized utilizing ground-state electron transfer from cobaltocene. This allows injecting up to eight electrons per NC into the band-edge state and maintaining the doping level for at least a month at room temperature. Doping is confirmed by inter-more » and intra-band optical absorption, as well as by carrier dynamics. Finally, FET measurements of doped NC films and the demonstration of a p-n diode provide additional evidence that the developed doping procedure allows for persistent incorporation of electrons into the quantum-confined NC states.« less
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