Multilayer Quantum Well–Dot InGaAs Heterostructures in GaAs-based Photovoltaic Converters

Journal Article · Mon Oct 15 04:00:00 EDT 2018 · Semiconductors

DOI:https://doi.org/10.1134/S1063782618100147· OSTI ID:22749777

Kalyuzhnyy, N. A. ^[1]; Nadtochiy, A. M.; Maximov, M. V. ^[2]; Nevedomskiy, V. N.; Sokura, L. A. ^[1]; Rouvimov, S. S. ^[3]; Shvarts, M. Z. ^[1]; Zhukov, A. E. ^[2]

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1. Ioffe Institute (Russian Federation)
2. St. Petersburg Academic University (Russian Federation)
3. University of Notre Dame (United States)

GaAs photovoltaic converters containing quantum well-dot (QWD) heterostructures are studied. The QWD properties are intermediate between those of quantum wells (QWs) and quantum dots. The QWDs are obtained by the epitaxial deposition of In{sub 0.4}Ga{sub 0.6}As with a nominal thickness of 8 single layers by metal-organic vapor phase epitaxy. QWDs are a dense array of elastically strained islands that localize carriers in three directions and are formed by a local increase in the indium concentration and/ or InGaAs-layer thickness. There are two quantum-well levels of varied nature in structures with QWDs. These levels are manifested in the spectral characteristics of GaAs photovoltaic converters. A short-wavelength peak with a maximum at around 935 nm is associated with absorption in the residual QW, and the long-wavelength peak (1015–1030 nm) is due to absorption in the QWDs. Investigation by transmission electron microscopy demonstrates that an increase in the number of InGaAs layers leads to stronger elastic stresses, which, in turn, increases the carrier confinement energy in the QWDs and lead to a corresponding long-wavelength shift of the internal quantum efficiency spectrum.

• OSTI ID: 22749777
• Journal Information: Semiconductors, Journal Name: Semiconductors Journal Issue: 10 Vol. 52; ISSN SMICES; ISSN 1063-7826
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
GALLIUM ARSENIDES
INDIUM ARSENIDES
ORGANOMETALLIC COMPOUNDS
PHOTOVOLTAIC EFFECT
QUANTUM DOTS
QUANTUM EFFICIENCY
QUANTUM WELLS
SOLAR CELLS
TRANSMISSION ELECTRON MICROSCOPY
VAPOR PHASE EPITAXY