Optimization towards high density quantum dots for intermediate band solar cells grown by molecular beam epitaxy

Journal Article · Mon Feb 08 04:00:00 EST 2010 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3313938· OSTI ID:21347268

Zhou, D; Sharma, G; Fimland, B O ^[1]; Thomassen, S F; Reenaas, T W ^[2]

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1. Department of Electronics and Telecommunications, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim (Norway)
2. Department of Physics, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim (Norway)

We report high density quantum dots (QDs) formation with optimized growth temperature and V/III ratio. At lower growth temperature, QD density is increased, due to smaller surface migration length of In adatoms. With higher V/III, the QD density is higher but it results in large clusters formation and decreases the QD uniformity. The QD solar cell was fabricated and examined. An extended spectral response in contrast to the GaAs reference cell was presented but the external quantum efficiency at energies higher than GaAs band gap is reduced, resulting from the degradation for the emitter above the strained QD layers.

• OSTI ID: 21347268
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 6 Vol. 96; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
ARSENIC COMPOUNDS
ARSENIDES
CRYSTAL GROWTH
CRYSTAL GROWTH METHODS
DIMENSIONS
DIRECT ENERGY CONVERTERS
EFFICIENCY
ENERGY GAP
EPITAXY
EQUIPMENT
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
LAYERS
LENGTH
MATERIALS
MIGRATION LENGTH
MOLECULAR BEAM EPITAXY
NANOSTRUCTURES
OPTIMIZATION
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PNICTIDES
QUANTUM DOTS
QUANTUM EFFICIENCY
RESIDUAL STRESSES
SEMICONDUCTOR MATERIALS
SOLAR CELLS
SOLAR EQUIPMENT
SPECTRAL RESPONSE
STRESSES