Improvement of performance of GaAs solar cells by inserting self-organized InAs/InGaAs quantum dot superlattices

This study demonstrates the feasibility of improving the performance of a quantum dot (QD) intermediate band solar cell (SC) by capping an InGaAs layer on the InAs QDs and inserting GaAs spacer layers. For comparison, a GaAs reference SC of the same p-i-n structure but without InAs QDs is grown. The...

Full description

Saved in:

Bibliographic Details
Published in:	Solar energy materials and solar cells Vol. 113; pp. 1 - 6
Main Authors:	Sayari, A., Ezzidini, M., Azeza, B., Rekaya, S., Shalaan, E., Yaghmour, S.J., Al-Ghamdi, A.A., Sfaxi, L., M’ghaieth, R., Maaref, H.
Format:	Journal Article
Language:	English
Published:	Amsterdam Elsevier B.V 01-06-2013 Elsevier
Subjects:	Applied sciences Direct energy conversion and energy accumulation Electrical engineering. Electrical power engineering Electrical power engineering Energy Exact sciences and technology Gallium arsenide Gallium arsenides III–V Heterostructures Indium arsenides Indium gallium arsenides Multi-stacking Natural energy Performance enhancement Photoelectric conversion Photovoltaic cells Photovoltaic conversion Quantum dot solar cells Quantum dots Solar cells Solar cells. Photoelectrochemical cells Solar energy Spectra Spectroscopic ellipsometry III–V Heterostructures Multi-stacking Spectroscopic ellipsometry Quantum dot solar cells Performance evaluation Intermediate band solar cell Quantum dot Barrier layer Wetting Stacking Photoluminescence p i n junctions III―V Heterostructures III-V compound Gallium arsenide solar cells Solar cell Dielectric function Self organization Molecular beam epitaxy Feasibility Photoelectric current Optical absorption Comparative study Heterostructures Superlattice
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	This study demonstrates the feasibility of improving the performance of a quantum dot (QD) intermediate band solar cell (SC) by capping an InGaAs layer on the InAs QDs and inserting GaAs spacer layers. For comparison, a GaAs reference SC of the same p-i-n structure but without InAs QDs is grown. The two devices were grown by solid source molecular beam epitaxy (SS-MBE) on epiready (001) n+-GaAs substrates and the InAs QDs structure is highly stacked and well-aligned. The two SCs were investigated by sepectroscopic ellipsometry (SE), in the photon energy range of 1–6eV, photoluminescence (PL) and photo-absorption measurements. The two major spectral features observed in the dielectric function spectra of the InAs QDs SC at ∼3eV and ∼4.5eV are attributed to the E1 and E2 critical point structures of GaAs and InAs, respectively. The PL spectrum of the InAs QDs in the GaAs matrix is higher and presents an asymmetric shape, which indicated the growth of a high-quality multistacked InAs QDs structure and the contribution of larger and relatively smaller QDs to PL spectrum. The electrical conversion at the infrared range of λ=850–1300nm for the InAs QDs SC is demonstrated by photocurrent spectra. The enhanced absorption performance (up to 1280nm) of the QDs SC was attributed to the optical absorption from InAs QDs, wetting layer and InGaAs layer of the InAs/InGaAs/GaAs QD heterostructure. ► GaAs-based SC with multistack of InAs/InGaAs QDs has been fabricated by SS-MBE. ► Optical properties of the InAs QDs SC were investigated by SE and PL. ► Electrical conversion at the infrared range is demonstrated by photocurrent spectra. ► Absorption performance of the QDs SC was enhanced up to 1280nm.
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0927-0248 1879-3398
DOI:	10.1016/j.solmat.2013.01.033