skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Over 30{percent} efficient InGaP/GaAs tandem solar cells

Abstract

A two-terminal monolithic InGaP/GaAs tandem solar cell with a new efficiency record of 30.28{percent} is realized with a practical large area of 4 cm{sup 2} under one-sun air-mass 1.5 global illumination. We report improvements of the tandem cell performance by introducing a double-hetero (hereafter DH) structure InGaP tunnel junction, in which the InGaP layers are surrounded by high band gap AlInP barriers. The DH structure by AlInP barriers increase the peak current of InGaP tunnel junction. The AlInP barrier directly below the InGaP top cell, which takes the part of a back surface field (hereafter BSF) layer, is found to be considerably effective in reflecting minority carriers in the top cell. The AlInP BSF layer does not only form a high potential barrier but also prevents the diffusion of zinc from a high doped tunnel junction toward the top cell during epitaxial growth. Furthermore, an InGaP tunnel junction reduces the absorption loss, which exists in a GaAs tunnel junction, and increases the photogenerated current in the GaAs bottom cell. {copyright} {ital 1997 American Institute of Physics.}

Authors:
; ;  [1];  [2]
  1. Central Research Laboratory, Japan Energy Corporation, 3-17-35 Niizo-Minami, Toda, Saitama 335 (Japan)
  2. Japan Energy Research Center Company, Ltd., 1-11-9 Azabudai, Minato-ku, Tokyo 106 (Japan)
Publication Date:
OSTI Identifier:
463433
Resource Type:
Journal Article
Journal Name:
Applied Physics Letters
Additional Journal Information:
Journal Volume: 70; Journal Issue: 3; Other Information: PBD: Jan 1997
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; GALLIUM ARSENIDE SOLAR CELLS; EFFICIENCY; INDIUM PHOSPHIDE SOLAR CELLS; INDIUM COMPOUNDS; CARRIER LIFETIME; HETEROJUNCTIONS; EPITAXY; TUNNEL EFFECT; CHEMICAL VAPOR DEPOSITION

Citation Formats

Takamoto, T, Ikeda, E, Kurita, H, and Ohmori, M. Over 30{percent} efficient InGaP/GaAs tandem solar cells. United States: N. p., 1997. Web. doi:10.1063/1.118419.
Takamoto, T, Ikeda, E, Kurita, H, & Ohmori, M. Over 30{percent} efficient InGaP/GaAs tandem solar cells. United States. doi:10.1063/1.118419.
Takamoto, T, Ikeda, E, Kurita, H, and Ohmori, M. Wed . "Over 30{percent} efficient InGaP/GaAs tandem solar cells". United States. doi:10.1063/1.118419.
@article{osti_463433,
title = {Over 30{percent} efficient InGaP/GaAs tandem solar cells},
author = {Takamoto, T and Ikeda, E and Kurita, H and Ohmori, M},
abstractNote = {A two-terminal monolithic InGaP/GaAs tandem solar cell with a new efficiency record of 30.28{percent} is realized with a practical large area of 4 cm{sup 2} under one-sun air-mass 1.5 global illumination. We report improvements of the tandem cell performance by introducing a double-hetero (hereafter DH) structure InGaP tunnel junction, in which the InGaP layers are surrounded by high band gap AlInP barriers. The DH structure by AlInP barriers increase the peak current of InGaP tunnel junction. The AlInP barrier directly below the InGaP top cell, which takes the part of a back surface field (hereafter BSF) layer, is found to be considerably effective in reflecting minority carriers in the top cell. The AlInP BSF layer does not only form a high potential barrier but also prevents the diffusion of zinc from a high doped tunnel junction toward the top cell during epitaxial growth. Furthermore, an InGaP tunnel junction reduces the absorption loss, which exists in a GaAs tunnel junction, and increases the photogenerated current in the GaAs bottom cell. {copyright} {ital 1997 American Institute of Physics.}},
doi = {10.1063/1.118419},
journal = {Applied Physics Letters},
number = 3,
volume = 70,
place = {United States},
year = {1997},
month = {1}
}