Journal ArticleDOI
GaAs Clusters in the Quantum Size Regime: Growth on High Surface Area Silica by Molecular Beam Epitaxy.
C. J. Sandroff,J. P. Harbison,R. Ramesh,M. J. Andrejco,M. S. Hegde,C. C. Chang,E. M. Vogel,D. M. Hwang +7 more
TLDR
Study of the microcrystallite surfaces by x-ray photoelectron spectroscopy shows that they are covered with a shell of native oxides of gallium and arsenic, whose presence could explain the low luminescence efficiency of the clusters.Abstract:
Molecular beam epitaxy has been used to grow microcrystalline clusters of gallium arsenide (GaAs) in the size range from 2.5 to 60 nanometers on high-purity, amorphous silica supports. High-resolution transmission electron microscopy reveals that clusters as small as 3.5 nanometers have good crystalline order with a lattice constant equal to that of bulk GaAs. Study of the microcrystallite surfaces by x-ray photoelectron spectroscopy shows that they are covered with a shell (1.0 to 1.5 nanometers thick) of native oxides of gallium and arsenic (Ga2O3 and As2O3), whose presence could explain the low luminescence efficiency of the clusters. Optical absorption spectra of the supported GaAs are consistent with the blue-shifted band edge expected for semiconductor microcrystallites in the quantum size regime.read more
Citations
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Theory of the linear and nonlinear optical properties of semiconductor microcrystallites
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References
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Book
Practical surface analysis: By auger and x-ray photoelectron spectroscopy
David Briggs,M. P. Seah +1 more
Journal ArticleDOI
Electronic wave functions in semiconductor clusters: experiment and theory
Journal ArticleDOI
Theory of the linear and nonlinear optical properties of semiconductor microcrystallites
TL;DR: In this article, the optical properties of ideal semiconductor crystallites so small that they show quantum confinement in all three dimensions [quantum dots (QD's)] were analyzed theoretically, and the phonon broadening of these lines was considered.
Journal Article
Theory of the linear and nonlinear optical properties of semiconductor microcrystallites
TL;DR: In the limit of a QD much smaller than the bulk exciton size, the linear spectrum will be a series of lines, and the phonon broadening of these lines is considered.
Journal ArticleDOI
Dramatic enhancement in the gain of a GaAs/AlGaAs heterostructure bipolar transistor by surface chemical passivation
TL;DR: In this paper, a passivated nonradiative recombination center at the periphery of a GaAs/AlGaAs heterostructure bipolar transistor was proposed to increase the current gain of the device at low collector currents.