Accurate Measurement of the Optical Constants n and k for a Series of 57 Inorganic and Organic Liquids for Optical Modeling and Detection

For optical modeling and other purposes, we have created a library of 57 liquids for which we have measured the complex optical constants n and k. These liquids vary in their nature, ranging in properties that include chemical structure, optical band strength, volatility, and viscosity. By obtaining the optical constants, one can model most optical phenomena in media and at interfaces including reflection, refraction, and dispersion. Based on the works of others, we have developed improved protocols using multiple path lengths to determine the optical constants n/k for dozens of liquids, including inorganic, organic, and organophosphorus compounds. Detailed descriptions of the measurement and data reduction protocols are discussed; agreement of the derived optical constant n and k values with literature values are presented. We also present results using the n/k values as applied to an optical modeling scenario whereby the derived data are presented and tested for models of 1 µm and 100 µm layers for dimethyl methylphosphonate (DMMP) on both metal (aluminum) and dielectric (soda lime glass) substrates to show substantial differences between the reflected signal from highly reflective substrates and less-reflective substrates.

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Analysis of Cu(InGa)Se2 Alloy Film Optical Properties and the Effect of Cu Off-Stoichiometry

MRS Proceedings ◽

10.1557/proc-865-f1.4 ◽

2005 ◽

Vol 865 ◽

Cited By ~ 1

Author(s):

P. D. Paulson ◽

S. H. Stephens ◽

W. N. Shafarman

Keyword(s):

Optical Constants ◽

Soda Lime ◽

Alloy Film ◽

Relative Volume ◽

Soda Lime Glass ◽

Distinctive Features ◽

Glass Substrates ◽

Wide Range ◽

Two Phases

AbstractVariable angle spectroscopic ellipsometry has been used to characterize Cu(InGa)Se2 thin films as a function of relative Ga content and to study the effects of Cu off-stoichiometry. Uniform Cu(InGa)Se2 films were deposited on Mo-coated soda lime glass substrates by elemental evaporation with a wide range of relative Cu and Ga concentrations. Optical constants of Cu(InGa)Se2 were determined over the energy range of 0.75–C4.6 eV for films with 0 ≤ Ga/(In+Ga) ≤ 1 and used to determine electronic transition energies. Further, the changes in the optical constants and electronic transitions as a function of Cu off-stoichiometry were determined in Cu-In-Ga-Se films with Cu atomic concentration varying from 10 to 25 % and Ga/(In+Ga) = 0.3. Films with Cu in the range 16–24 % are expected to contain 2 phases so an effective medium approximation is used to model the data. This enables the relative volume fractions of the two phases, and hence composition, to be determined. Two distinctive features are observed in the optical spectra as the Cu concentration decreases. First, the fundamental bandgaps are shifted to higher energies. Second, the critical point features at higher energies become broader suggesting degradation of the crystalline quality of the material.

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DETERMINATION OF THE OPTICAL CONSTANTS OF InxSey THIN FILMS DEPOSITED BY EVAPORATION AND COEVAPORATION

Surface Review and Letters ◽

10.1142/s0218625x02004220 ◽

2002 ◽

Vol 09 (05n06) ◽

pp. 1687-1691 ◽

Cited By ~ 3

Author(s):

J. SANDINO ◽

G. GORDILLO

Keyword(s):

Thin Films ◽

Optical Constants ◽

Soda Lime ◽

Soda Lime Glass ◽

Interference Effects ◽

Spectral Transmittance ◽

Cauchy Equation ◽

Glass Substrates ◽

Special Procedure

In x Se y thin films, grown on soda lime glass substrates in the In 6 Se 7 phase by evaporation of the In 2 Se 3 compound and in the In 2 Se 3 phase by coevaporation of In and Se, were optically characterized through spectral transmittance measurements. A special procedure was developed to determine the thickness d and the optical constants (refractive index n, absorption coefficient α, and optical gap Eg). This includes experimental measurements of the spectral transmittance and the use of a model taking into account interference effects induced by internal reflections presented in the interfaces substrate/film and film/air and the fitting of the n vs. λ curve to the Cauchy equation (n = A + B/λ2). The optical constants of the In x Se y thin films were corrected comparing the experimental transmittance spectrum with the theoretical one. The results revealed that the optical constants of the In x Se y films were significantly affected by the deposition method.

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Preparation of CuInGaSe2 Absorber Layer by Nanoparticles-Based Spray Deposition

MRS Proceedings ◽

10.1557/proc-836-l5.10 ◽

2004 ◽

Vol 836 ◽

Author(s):

Ki-Hyun Kim ◽

Young-Gab Chun ◽

Byung-Ok Park ◽

Kyung-Hoon Yoon

Keyword(s):

Spray Deposition ◽

Soda Lime ◽

Inert Atmosphere ◽

Absorber Layer ◽

Step Motor ◽

Soda Lime Glass ◽

Soda Lime Glass Substrate ◽

Glass Substrates ◽

Spray System ◽

Cigs Nanoparticles

ABSTRACTCIGS nanoparticles for the CIGS absorber layer have been synthesized by low temperature colloidal routes. The CIGS absorber layers for solar cells have been prepared by spray deposition of CIGS nanoparticle precursors (∼20 nm) in glove box under inert atmosphere. An automatic air atomizing nozzle spray system with computer controlled X-Y step motor system was used to spray. The nanoparticle precursor CIGS film was deposited onto molybdenum-coated soda-lime glass substrates (2.5 cm × 5.0 cm) heated to 160°C. The film thickness in the range of 2 μm ± 0.3 μm was attained by spraying of 3 mM colloidal over an area of 12.5 cm2. The coalescence between particles was observed in the CIGS absorber layer under post-treatment of over 550 °C. This is related to the reactive sintering among the nanoparticles to reduce surface energy of the particles. The CuxSe thin film, formed on Mo film by evaporation, improved adhesion between CIGS and Mo layers and enhanced the coalescence of the particles in the CIGS layer. These are closely related to the fluxing of Cu2Se phase which has relatively low melting temperature. The CdS buffer layer was deposited on the CIGS/Mo/soda-lime glass substrate by chemical bath deposition. The CIGS nanoparticles-based absorber layers were characterized by using energy dispersive spectroscopy (EDS), x-ray diffraction (XRD) and high-resolution scanning electron microscopy (HRSEM).

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Selective formation of GaN-based nanorod heterostructures on soda-lime glass substrates by a local heating method

Nanotechnology ◽

10.1088/0957-4484/22/20/205602 ◽

2011 ◽

Vol 22 (20) ◽

pp. 205602 ◽

Cited By ~ 13

Author(s):

Young Joon Hong ◽

Yong-Jin Kim ◽

Jong-Myeong Jeon ◽

Miyoung Kim ◽

Jun Hee Choi ◽

...

Keyword(s):

Local Heating ◽

Soda Lime ◽

Soda Lime Glass ◽

Heating Method ◽

Glass Substrates ◽

Selective Formation

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Preparation and Characterization of Cu2Zn(GexSn1-x)Se4 Thin-films from Sputtered Elemental Precursors

MRS Proceedings ◽

10.1557/opl.2014.418 ◽

2014 ◽

Vol 1670 ◽

Author(s):

Antony Jan ◽

Yesheng Yee ◽

Bruce M. Clemens

Keyword(s):

Band Gap ◽

Low Cost ◽

Solar Spectrum ◽

Soda Lime ◽

Soda Lime Glass ◽

Material System ◽

Direct Band Gap ◽

Glass Substrates ◽

Before And After ◽

Direct Band

ABSTRACTThin-film absorber layers for photovoltaics have attracted much attention for their potential for low cost per unit power generation, due both to reduced material consumption and to higher tolerance for defects such as grain boundaries. Cu2ZnGeSe4 (CZGSe) comprises one such material system which has a near-optimal direct band gap of 1.6 eV for absorption of the solar spectrum, and is made primarily from earth-abundant elements.CZGSe metallic precursor films were sputtered from Cu, Zn, and Ge onto Mo-coated soda lime glass substrates. These were then selenized in a two-zone close-space sublimation furnace using elemental Se as the source, with temperatures in the range of 400 to 500 C, and at a variety of background pressures. Films approximately 1-1.5 µm thick were obtained with the expected stannite crystal structure.Next, Cu2ZnSnSe4 (CZTSe), which has a direct band gap of 1.0 eV, was prepared in a similar manner and combined with CZGSe as either compositionally homogeneous or layered absorbers. The compositional uniformity of selenide absorbers made by selenizing compositionally homogeneous Cu-Zn-Ge-Sn precursor layers was determined and the band gap as a function of composition was investigated in order to demonstrate that the band gap is tuneable for a range of compositions. For layered Cu-Zn-Ge/Cu-Zn-Sn precursor films, the composition profile was measured before and after selenization to assess the stability of the layered structure, and its applicability for forming a band-gap-graded device for improved current collection.

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Second harmonic generation of fluorine-doped zinc oxide thin films grown on soda-lime glass substrates by a chemical spray technique

Optics Communications ◽

10.1016/j.optcom.2006.08.042 ◽

2007 ◽

Vol 269 (2) ◽

pp. 370-377 ◽

Cited By ~ 18

Author(s):

O.G. Morales-Saavedra ◽

L. Castañeda

Keyword(s):

Thin Films ◽

Zinc Oxide ◽

Second Harmonic Generation ◽

Harmonic Generation ◽

Second Harmonic ◽

Soda Lime ◽

Soda Lime Glass ◽

Glass Substrates ◽

Chemical Spray ◽

Spray Technique

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Fabrication of microchannels on soda-lime glass substrates with a Nd:YVO4 laser

Optics and Lasers in Engineering ◽

10.1016/j.optlaseng.2014.06.005 ◽

2014 ◽

Vol 63 ◽

pp. 11-18 ◽

Cited By ~ 31

Author(s):

Daniel Nieto ◽

Tamara Delgado ◽

María Teresa Flores-Arias

Keyword(s):

Soda Lime ◽

Soda Lime Glass ◽

Glass Substrates

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Influence of Deposition Time and Source-Substrate Distance on Properties of CdTe Thin Films Using Close-Spaced Sublimation at Higher Source Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.716.325 ◽

2013 ◽

Vol 716 ◽

pp. 325-327

Author(s):

Xiao Yan Dai ◽

Cheng Wu Shi ◽

Yan Ru Zhang ◽

Min Yao

Keyword(s):

Thin Films ◽

Deposition Time ◽

Near Infrared ◽

Soda Lime ◽

Soda Lime Glass ◽

X Ray ◽

Source Temperature ◽

Glass Substrates ◽

Substrate Distance ◽

Cdte Thin Films

In this paper, CdTe thin films were deposited on soda-lime glass substrates using CdTe powder as a source by close-spaced sublimation at higher source temperature of 700°C. The influence of the deposition time and the source-substrate distance on the chemical composition, crystal phase, surface morphology and optical band gap of CdTe thin films was systemically investigated by energy dispersive X-ray spectroscopy, X-ray diffraction, scanning electron microscope and the ultraviolet-visible-near infrared absorption spectra, respectively. At the deposition time of 60 min and the source-substrate distance of 5 mm, the CdTe thin films had pyramid appearance with the grain size of 15 μm.

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