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Title: Effect on Sb on the Properties of GaInP Top Cells: Preprint

Abstract

It is well known that the efficiency of GaInP/GaAs tandem solar cells is limited by the band gap of the GaInP top cell, which, in turn, is determined by the degree of compositional ordering in GaInP base layer. Attempts to raise the band gap by the addition of Al to the top cell have met with limited success due to the strong affinity between Al and oxygen. Here we investigate a different approach. It has been shown that the presence of antimony on the surface of GaInP during its growth suppresses the ordering process and increases the band gap. In this paper, we study the effects of Sb on the properties of GaInP top cells. We show that, in addition to raising the band gap of GaInP, it also increases the incorporation of Zn and changes the relative incorporation of Ga and In. These effects depend strongly on the substrate orientation, growth temperature and rate, and the Sb/P ratio in the gas phase. We show that the band gap of the GaInP top cell (and the Voc) can be increased without reducing the minority carrier collection efficiency. The implications of these results are presented and discussed.

Authors:
; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
891548
Report Number(s):
NREL/CP-520-39903
TRN: US200622%%90
DOE Contract Number:
AC36-99-GO10337
Resource Type:
Conference
Resource Relation:
Conference: Presented at the 2006 IEEE 4th World Conference on Photovoltaic Energy Conversion (WCPEC-4), 7-12 May 2006, Waikoloa, Hawaii
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; AFFINITY; ANTIMONY; EFFICIENCY; ENERGY CONVERSION; ORGANIC COMPOUNDS; ORIENTATION; OXYGEN; SOLAR CELLS; SUBSTRATES; VOLATILE MATTER; PV; TANDEM SOLAR CELLS; BAND GAP; MINORITY CARRIER; DOPING; TRIPLE-JUNCTION; Solar Energy - Photovoltaics

Citation Formats

Olson, J. M., McMahon, W. E., and Kurtz, S. Effect on Sb on the Properties of GaInP Top Cells: Preprint. United States: N. p., 2006. Web. doi:10.1109/WCPEC.2006.279574.
Olson, J. M., McMahon, W. E., & Kurtz, S. Effect on Sb on the Properties of GaInP Top Cells: Preprint. United States. doi:10.1109/WCPEC.2006.279574.
Olson, J. M., McMahon, W. E., and Kurtz, S. Mon . "Effect on Sb on the Properties of GaInP Top Cells: Preprint". United States. doi:10.1109/WCPEC.2006.279574. https://www.osti.gov/servlets/purl/891548.
@article{osti_891548,
title = {Effect on Sb on the Properties of GaInP Top Cells: Preprint},
author = {Olson, J. M. and McMahon, W. E. and Kurtz, S.},
abstractNote = {It is well known that the efficiency of GaInP/GaAs tandem solar cells is limited by the band gap of the GaInP top cell, which, in turn, is determined by the degree of compositional ordering in GaInP base layer. Attempts to raise the band gap by the addition of Al to the top cell have met with limited success due to the strong affinity between Al and oxygen. Here we investigate a different approach. It has been shown that the presence of antimony on the surface of GaInP during its growth suppresses the ordering process and increases the band gap. In this paper, we study the effects of Sb on the properties of GaInP top cells. We show that, in addition to raising the band gap of GaInP, it also increases the incorporation of Zn and changes the relative incorporation of Ga and In. These effects depend strongly on the substrate orientation, growth temperature and rate, and the Sb/P ratio in the gas phase. We show that the band gap of the GaInP top cell (and the Voc) can be increased without reducing the minority carrier collection efficiency. The implications of these results are presented and discussed.},
doi = {10.1109/WCPEC.2006.279574},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2006},
month = {Mon May 01 00:00:00 EDT 2006}
}

Conference:
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  • The summary of this report is that: (1) Sb can be used to increase V{sub oc} of a GaInP top cell; (2) the photovoltaic quality of GaInP is relatively unaffected by the presence of Sb; and (3) Sb-doped GaInP/GaAs tandem cells show promise for achieving efficiencies over 32%.
  • It is well known that the efficiency of GaInP/GaAs tandem solar cells is limited by the band gap of the GaInP top cell, which, in turn, is determined by the degree of compositional ordering in the GaInP base layer. Attempts to raise the band gap by the addition of Al to the top cell have met with limited success due to the strong affinity between Al and oxygen. Here we investigate a different approach. It has been shown that the presence of antimony on the surface of GaInP during its growth suppresses the ordering process and increases the band gap.more » In this paper, we study the effects of Sb on the properties of GaInP top cells. We show that, in addition to raising the band gap of GaInP, it also increases the incorporation of Zn and changes the relative incorporation of Ga and In. These effects depend strongly on the substrate orientation, growth temperature and rate, and the Sb/P ratio in the gas phase. We show that the band gap of the GaInP top cell (and the Voc) can be increased without reducing the minority carrier collection efficiency. The implications of these results are presented and discussed.« less
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  • Presented at the 2001 NCPV Program Review Meeting: A study of the stability of GaInP/GaAs tandem cells under concentration, to enhance understanding of long-term reliability issues.