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Title: Using MOVPE Growth to Generate Tomorrow's Solar Electricity

Abstract

No abstract prepared.

Authors:
; ; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
901956
DOE Contract Number:
AC36-99-GO10337
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Crystal Growth; Journal Volume: 298; Journal Issue: 2007
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; ELECTRICITY; SOLAR ENERGY; NATIONAL RENEWABLE ENERGY LABORATORY; Solar Energy - Photovoltaics

Citation Formats

Kurtz, S., Friedman, D., Geisz, J., and McMahon, W. Using MOVPE Growth to Generate Tomorrow's Solar Electricity. United States: N. p., 2007. Web. doi:10.1016/j.jcrysgro.2006.10.176.
Kurtz, S., Friedman, D., Geisz, J., & McMahon, W. Using MOVPE Growth to Generate Tomorrow's Solar Electricity. United States. doi:10.1016/j.jcrysgro.2006.10.176.
Kurtz, S., Friedman, D., Geisz, J., and McMahon, W. Mon . "Using MOVPE Growth to Generate Tomorrow's Solar Electricity". United States. doi:10.1016/j.jcrysgro.2006.10.176.
@article{osti_901956,
title = {Using MOVPE Growth to Generate Tomorrow's Solar Electricity},
author = {Kurtz, S. and Friedman, D. and Geisz, J. and McMahon, W.},
abstractNote = {No abstract prepared.},
doi = {10.1016/j.jcrysgro.2006.10.176},
journal = {Journal of Crystal Growth},
number = 2007,
volume = 298,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • We have recently reported high efficiencies in a monolithic III-V triple-junction solar cell design that is grown inverted with a metamorphic 1.0 eV bottom In{sub .27}Ga{sub .73}As junction. The biaxial stress and strain grown into this highly lattice-mismatched junction can be controlled by varying the design of a step-graded Ga{sub x}In{sub 1-x}P buffer layer, in which most, but not all, of the 1.9% misfit strain is relieved. A multi-beam optical stress sensor (MOSS) is a convenient tool for in situ measurement of stress during metal-organic vapor phase epitaxy (MOVPE) for the optimization of solar cell performance. The analysis of stressmore » from curvature data is complicated by significant temperature effects due to relatively small thermal gradients in our atmospheric-pressure MOVPE reactor. These temperature effects are discussed and approximations made to allow practical analysis of the data. The results show excellent performance of inverted In{sub .27}Ga{sub .73}. As solar cells grown with slight compressive stress, but degradation under tensile stress. The best devices had a V{sub oc} of 0.54 V and a dislocation density in the low 10{sup 6} cm{sup -2}. The in situ stress data is also compared with ex situ strain data derived from X-ray diffraction measurements.« less
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