Extracting calibrated parameters from imaging ellipsometric measurement

Metals are commonly used in plasmonic devices because of their strong plasmonic property. However, such properties are not easily tuned. For applications such as spatial light modulators and beam steering, tunable plasmonic properties are essential, and neither metals nor other plasmonic materials possess truly tunable plasmonic properties. In this work, we show that the silver alloy silver–ytterbium (Ag-Yb) possesses tunable plasmonic properties; its plasmonic response strength can be adjusted as a function of Yb concentration. Such tunability can be explained in terms of the influence of Yb on bound charge and interaction of its dielectric with the dielectric of Ag. The change in transition characteristics progressively weakens Ag’s plasmonic properties. With a spectral ellipsometric measurement, it was shown that the Ag-Yb alloy thin film retains the properties of Ag with high transmission efficiency. The weakened surface plasmon coupling strength without dramatic change in the coupling wavelengths implies that the tunability of the Ag-Yb alloy is related to its volume ratio. The principle mechanism of the plasmonic change is theoretically explained using a model. This work points to a potential new type of tunable plasmonic material.

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Key Radicals for Hetero-Epitaxial Growth of 3C-SiC on Silicon Substrates

Materials Science Forum ◽

10.4028/www.scientific.net/msf.483-485.209 ◽

2005 ◽

Vol 483-485 ◽

pp. 209-212

Author(s):

Hideki Shimizu ◽

Kensaku Hisada ◽

Yosuke Aoyama

Keyword(s):

Epitaxial Growth ◽

Flow Rate ◽

Hydrogen Plasma ◽

Silicon Substrates ◽

X Ray Diffraction ◽

Ellipsometric Measurement ◽

X Ray ◽

Hydrogen Radicals ◽

Sic Films ◽

Reflection Electron Diffraction

Effects of the flow rate of C3H8 passed through hydrogen plasma on deposition rates and^microstructures of 3C-SiC films on Si (100) substrate were investigated by a reflection electron diffraction, an X-ray diffraction and an ellipsometric measurement. The deposition rate of the films increased independently of the flow rate of C3H8 with increasing the flow rate of SiH4. The films grown with increasing the flow rate of C3H8 kept single crystalline structure even at high flow rate of SiH4. Hydrogen radicals generated from C3H8 decomposition by plasma increase with increasing the flow rate of C3H8, and play important rolls to keep epitaxial growth.

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Variable Angle of Incidence Spectroscopic Ellipsometric Measurement of the Franz-Keloysh Effect in Modfet Structures

MRS Proceedings ◽

10.1557/proc-77-761 ◽

1986 ◽

Vol 77 ◽

Cited By ~ 5

Author(s):

P. G. Snyder ◽

J. E. Oh ◽

J. A. Woollam

Keyword(s):

Electric Field ◽

Bandgap Energy ◽

Model Parameters ◽

Angle Of Incidence ◽

Internal Electric Field ◽

Ellipsometric Measurement ◽

Band Bending ◽

Variable Angle ◽

Two Samples ◽

Franz Keldysh Effect

ABSTRACTIt has been shown recently that variable angle of incidence spectroscopie ellipsometry (VASE) is a sensitive technique for determining semiconductor multilayer model parameters, e.g. layer thicknesses and ternary compositions. In this paper we show that VASE is, in addition, sensitive to the Franz-Keldysh effect induced by band bending in the barrier layer of a GaAs-AlGaAs-GaAs (MODFET) structure. VASE measurements differ from electro-reflectance and photoreflectance, in that the internal heterojunction region electric field is directly probed, without the application of a modulating field. The Franz-Keldysh effect appears in the VASE spectra near the AlGaAs bandgap energy. Data for two samples, with different doping profiles, are quantitatively modeled to determine the internal electric field amplitudes.

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Ellipsometric measurement of skin refractive index in vivo

Bioengineering and the Skin ◽

10.1007/978-94-009-7310-7_32 ◽

1981 ◽

pp. 291-302

Author(s):

P. T. Pugliese ◽

A. J. Milligan

Keyword(s):

Refractive Index ◽

Ellipsometric Measurement

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ChemInform Abstract: Reactions of NO2/ N2O4with Ag: A Surface Enhanced Raman Scattering and Ellipsometric Measurement.

Chemischer Informationsdienst ◽

10.1002/chin.198615032 ◽

1986 ◽

Vol 17 (15) ◽

Author(s):

P. B. DORAIN ◽

J. E. BOGGIO

Keyword(s):

Raman Scattering ◽

Surface Enhanced Raman Scattering ◽

Ellipsometric Measurement ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Enhanced Raman Scattering

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Ellipsometric Measurement of Bacterial Films at Metal-Electrolyte Interfaces

Applied and Environmental Microbiology ◽

10.1128/aem.64.10.3690-3697.1998 ◽

1998 ◽

Vol 64 (10) ◽

pp. 3690-3697 ◽

Cited By ~ 13

Author(s):

J. P. Busalmen ◽

S. R. de Sánchez ◽

D. J. Schiffrin

Keyword(s):

Film Growth ◽

Film Formation ◽

High Sensitivity ◽

Bacterial Attachment ◽

Optical Measurements ◽

Ellipsometric Measurement ◽

Effective Medium Model ◽

Bacterial Films ◽

Bacterial Film

ABSTRACT Ellipsometric measurements were used to monitor the formation of a bacterial cell film on polarized metal surfaces (Al-brass and Ti). Under cathodic polarization bacterial attachment was measured from changes in the ellipsometric angles. These were fitted to an effective medium model for a nonabsorbing bacterial film with an effective refractive index (nf ) of 1.38 and a thickness (df ) of 160 ± 10 nm. From the optical measurements a surface coverage of 17% was estimated, in agreement with direct microscopic observations. The influence of bacteria on the formation of oxide films was monitored by ellipsometry following the film growth in situ. A strong inhibition of metal oxide film formation was observed, which was assigned to the decrease in oxygen concentration due to the presence of bacteria. It is shown that the irreversible adhesion of bacteria to the surface can be monitored ellipsometrically. Electrophoretic mobility is proposed as one of the factors determining bacterial attachment. The high sensitivity of ellipsometry and its usefulness for the determination of growth of interfacial bacterial films is demonstrated.

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