Ultra-high frequency photoconductivity decay in GaAs/Ge/GaAs double heterostructure grown by molecular beam epitaxy

Journal Article · Mon Mar 04 04:00:00 EST 2013 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4794984· OSTI ID:22162774

Hudait, M. K.; Zhu, Y. ^[1]; Johnston, S. W. ^[2]; Maurya, D.; Priya, S. ^[3]; Umbel, R. ^[4]

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1. Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)
2. National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)
3. Center for Energy Harvesting Materials and Systems (CEHMS), Virginia Tech, Blacksburg, Virginia 24061 (United States)
4. Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)

GaAs/Ge/GaAs double heterostructures (DHs) were grown in-situ using two separate molecular beam epitaxy chambers. High-resolution x-ray rocking curve demonstrates a high-quality GaAs/Ge/GaAs heterostructure by observing Pendelloesung oscillations. The kinetics of the carrier recombination in Ge/GaAs DHs were investigated using photoconductivity decay measurements by the incidence excitation from the front and back side of 15 nm GaAs/100 nm Ge/0.5 {mu}m GaAs/(100)GaAs substrate structure. High-minority carrier lifetimes of 1.06-1.17 {mu}s were measured when excited from the front or from the back of the Ge epitaxial layer, suggests equivalent interface quality of GaAs/Ge and Ge/GaAs. Wavelength-dependent minority carrier recombination properties are explained by the wavelength-dependent absorption coefficient of Ge.

• OSTI ID: 22162774
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 9 Vol. 102; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION
CARRIER LIFETIME
CRYSTALLOGRAPHY
EXCITATION
GALLIUM ARSENIDES
GERMANIUM
INTERFACES
LAYERS
MOLECULAR BEAM EPITAXY
OSCILLATIONS
PHOTOCONDUCTIVITY
RECOMBINATION
SEMICONDUCTOR MATERIALS
SUBSTRATES
WAVELENGTHS
X RADIATION
X-RAY DIFFRACTION