(Invited) Porous Silicon Dissolution Monitoring and Optical Constants Measurement Using in Situ Photoconduction in HF

ABSTRACTA modular spectroscopic ellipsometer, capable of both in-situ and ex-situ operation, has been used to measure important growth parameters of GaAs/AIGaAs structures. The ex-situ measurements provided layer thicknesses and compositions of the grown structures. In-situ ellipsometric measurements allowed the determination of growth rates, layer thicknesses, and high temperature optical constants. By performing a regression analysis of the in-situ data in real-time, the thickness and composition of an AIGaAs layer were extracted during the MBE growth of the structure.

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In-situ measurements of alumina particle size and optical constants in composite solid propellant flames

10.2514/6.1987-1582 ◽

1987 ◽

Author(s):

QUINN BREWSTER ◽

DAVID PARRY

Keyword(s):

Particle Size ◽

Solid Propellant ◽

Optical Constants ◽

Alumina Particle ◽

In Situ Measurements ◽

Composite Solid Propellant ◽

Composite Solid

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Porous Silicon Structural Evolution from In-Situ Luminescence and Raman Measurements

MRS Proceedings ◽

10.1557/proc-431-171 ◽

1996 ◽

Vol 431 ◽

Author(s):

D. R. Tallant ◽

M. J. Kelly ◽

T. R. Guilinger ◽

R. L. Simpson

Keyword(s):

Porous Silicon ◽

Silicon Surface ◽

Structural Evolution ◽

Surface Oxidation ◽

Ethanol Solution ◽

Nonradiative Recombination ◽

Photoluminescence Intensity ◽

Exciton Migration ◽

Photoluminescence Mechanism

AbstractWe performed in-situ photoluminescence and Raman measurements on an anodized silicon surface in the HF/ethanol solution used for anodization. The porous silicon thereby produced, while resident in HF/ethanol, does not immediately exhibit intense photoluminescence. Intense photoluminescence develops spontaneously in HF/ethanol after 18–24 hours or with replacement of the HF/ethanol with water. These results support a quantum confinement mechanism in which exciton migration to traps and nonradiative recombination dominates the de-excitation pathways until silicon nanocrystals are physically separated and energetically decoupled by hydrofluoric acid etching or surface oxidation. The porous silicon surface, as produced by anodization, shows large differences in photoluminescence intensity and peak wavelength over millimeter distances. Parallel Raman measurements implicate nanometer-size silicon particles in the photoluminescence mechanism.

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In Situ Light Scattering Techniques for Determining Aerosol Size Distributions and Optical Constants

Light Scattering by Irregularly Shaped Particles ◽

10.1007/978-1-4684-3704-1_29 ◽

1980 ◽

pp. 243-246 ◽

Cited By ~ 2

Author(s):

Gerald W. Grams

Keyword(s):

Light Scattering ◽

Optical Constants ◽

Size Distributions

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Magnetic Properties of Ferrous Ferric Oxide Confined in Porous Silicon

Materials Science Forum ◽

10.4028/www.scientific.net/msf.663-665.1142 ◽

2010 ◽

Vol 663-665 ◽

pp. 1142-1145

Author(s):

Yuan Ming Huang ◽

Bao Gai Zhai ◽

Qing Lan Ma ◽

Ming Meng

Keyword(s):

Electron Microscopy ◽

Magnetic Properties ◽

Iron Oxide ◽

Porous Silicon ◽

Ferrous Iron ◽

Silicon Film ◽

X Ray ◽

Loop Measurement ◽

Scanning Electron

During the chemical synthesis nanometer-sized particles of ferrous iron oxide were in situ infiltrated into the mesopores in a porous silicon film. The microstructures of porous silicon and the magnetic properties of the nanometer-sized particles of the ferrous iron oxide were characterized with scanning electron microscopy, X-ray diffractometry, and the hysteresis loop measurement, respectively. Our results have demonstrated that the magnetic properties of the nanometer-sized Fe3O4 particles can be dramatically modified when they are confined into the mesopores of the porous silicon film.

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