Effects of buffer layers on the structural and electronic properties of InSb films

Journal Article · Mon Feb 14 23:00:00 EST 2005 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.1841466· OSTI ID:20668200

Weng, X; Rudawski, N G; Wang, P T; Goldman, R S; Partin, D L; Heremans, J ^[1]

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1. Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States)

We have investigated the effects of various buffer layers on the structural and electronic properties of n-doped InSb films. We find a significant decrease in room-temperature electron mobility of InSb films grown on low-misfit GaSb buffers, and a significant increase in room-temperature electron mobility of InSb films grown on high-misfit InAlSb or step-graded GaSb+InAlSb buffers, in comparison with those grown directly on GaAs. Plan-view transmission electron microscopy (TEM) indicates a significant increase in threading dislocation density for InSb films grown on the low-misfit buffers, and a significant decrease in threading dislocation density for InSb films grown on high-misfit or step-graded buffers, in comparison with those grown directly on GaAs. Cross-sectional TEM reveals the role of the film/buffer interfaces in the nucleation (filtering) of threading dislocations for the low-misfit (high-misfit and step-graded) buffers. A quantitative analysis of electron mobility and carrier-concentration dependence on threading dislocation density suggests that electron scattering from the lattice dilation associated with threading dislocations has a stronger effect on electron mobility than electron scattering from the depletion potential surrounding the dislocations. Furthermore, while lattice dilation is the predominant mobility-limiting factor in these n-doped InSb films, ionized impurity scattering associated with dopants also plays a role in limiting the electron mobility.

• OSTI ID: 20668200
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 4 Vol. 97; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM COMPOUNDS
CHARGE CARRIERS
COMPARATIVE EVALUATIONS
DISLOCATIONS
DOPED MATERIALS
ELECTRON DIFFRACTION
ELECTRON MOBILITY
GALLIUM ANTIMONIDES
GALLIUM ARSENIDES
IMPURITIES
INDIUM ANTIMONIDES
INTERFACES
LAYERS
NUCLEATION
POTENTIALS
TEMPERATURE RANGE 0273-0400 K
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY