Determination of Optical Properties of Fluorocarbon Polymer Thin Films by a Variable Angle Spectroscopic Ellipsometry

1999 ◽  
Vol 588 ◽  
Author(s):  
Kang-Kuk Lee ◽  
Jin-Goo Park ◽  
Hyung-Jae Shin
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Optical Properties ◽  
Optical Constants ◽  
Visible Spectrum ◽  
Phase Model ◽  
Lorentz Model ◽  
Three Phase ◽  
Variable Angle Spectroscopic Ellipsometry ◽  
Best Fit

AbstractOptical properties of vapor phase (VP) deposited and spin-coated fluorocarbon (FC) thin films on silicon substrates, such as refractive index, extinction coefficient and film thickness were characterized by a variable angle spectroscopic ellipsometry (VASE) in the range of 300–800 nm. A Lorentz model allows us to simulate the optical constants of the FC films with a minimum number of parameters while maintaining Kramers-Kronig (KK) consistency between the real and imaginary parts of the optical constants. FC films are nearly transparent over the visible spectrum, so it is possible to assume k (extinction coefficient) = 0 over part of the visible spectrum in a Cauchy model. To accurately simulate the obtained ellipsometric spectra, we performed a regression analysis in two steps assuming a three-phase and a four-phase model. The regression analysis was performed using the three-phase model and a best-fit mean-squared error (MSE) value of 1.717 (VP deposited FC film, Lorentz model) was obtained. However, the four-phase model was used to improve the best-fit result of 0.531 (VP deposited FC film, Lorentz model). The surface roughness layer was assumed to be a mixture of FC films and voids under the Bruggeman effective medium approximation (EMA). We found that the best-fit MSE was reduced when surface roughness was included.

Optical Properties of Cu2ZnSnSe4 Nanocrystalline Thin Films for Photovoltaic Devices

2015 ◽  
Vol 789-790 ◽  
pp. 90-94
Author(s):  
Anderson Dussan ◽  
Heiddy P. Quiroz ◽  
Jorge A. Calderón ◽  
Sandra M. López
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Refractive Index ◽  
Optical Properties ◽  
Extinction Coefficient ◽  
Optical Constants ◽  
High Surface ◽  
Photovoltaic Devices ◽  
Xrd Patterns ◽  
Nanocrystalline Thin Films

Presents a study of optical properties from transmittance measurements as a function of wavelength to CZTSe thin films (Cu2ZnSnSe4) using Bhattacharyya model and basic elements from the Swanepoel theory. The optical constants such as the absorption coefficient (α), the refractive index (n), the extinction coefficient (k) and physical properties such as gap (Eg), the real and imaginary part of the dielectric function (ε1 and ε2) and the film thickness (d), were determined. Gap values between 1.2 and 1.7 eV were obtained for compound when the mass (MX) of ZnSe was varied during the deposition stage. Inhomogeneity and high surface roughness were observed by SEM measurements for all samples. Size grain varying between 458.16 and 630.28 nm were obtained while the ZnSe binary mass varied from 0.171 to 0.153 g. Refractive index and extinction coefficient of Cu2ZnSnSe4 films were obtained for λ = 800 nm. A decrease of ε1 and ε2 was observed as the wavelength increases; it is associated with the presence of binary phases in the XRD patterns.

Optical Characteristics of Amorphous III-V Nitride Thin Films

2004 ◽  
Vol 831 ◽  
Author(s):  
Jebreel M. Khoshman ◽  
Martin E. Kordesch
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Absorption Coefficient ◽  
Optical Constants ◽  
Near Infrared ◽  
Crystalline Silicon ◽  
Rf Magnetron Sputtering ◽  
Lorentz Model ◽  
Glass Substrates ◽  
Angle Dependence

ABSTRACTThe optical constants and polarized optical properties of amorphous III-V nitride thin films, a-(Al, Ga, In) N, deposited by RF magnetron sputtering onto crystalline silicon, c-Si, (111) and glass substrates have been investigated over the wavelength range 300 – 1400 nm. The optical constants of a-AlN were obtained by analysis of the measured ellipsometric spectra through the Cauchy–Urbach model while the optical constants of a-(In, Ga) N were determined using the Tauc-Lorentz model. Analysis of the absorption coefficient of a-AlN (in the range 200 – 1400 nm) and a-GaN (in the range 300 – 1400 nm) show the optical bandgap to be 5.9 ± 0.05 and 3.44 ± 0.05 eV. The absorption coefficient of a-InN (in the range 300 – 1400 nm) as a function of photon energy shows the absorption edge to be about 1.74 ± 0.05 eV. From the angle dependence of the p-polarized reflectivity we deduced Brewster and principal angles of these films. Measurement of the polarized optical properties revealed a high transmissivity (70 % – 95 %) and low absorptivity (< 18 %) for all three thin films in the visible and near infrared regions.

Calculation of the optical constants of thin films with consideration of the surface roughness and the width of the spectrum of the probing radiation

1980 ◽  
Vol 32 (4) ◽  
pp. 388-390
Author(s):  
B. V. Panasenko ◽  
A. G. Gusev ◽  
I. S. Gainutdinov ◽  
E. A. Nesmelov ◽  
R. B. Tagirov
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Optical Constants

Optimization of Maximum VO2 Content in Polymorphous Oxides of Vanadium

2013 ◽  
Vol 538 ◽  
pp. 113-116 ◽  
Author(s):  
S.N. Svitasheva
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Optical Constants ◽  
Ellipsometric Method

Optical properties of thin films of vanadium thermally oxidized at air were studied by ellipsometric method using wavelength of He-Ne laser. Multipart composition of these films was revealed and method of optimization of technological conditions based on dynamic of changing optical constants near 68°C was developed.

Effects of alloying on the optical properties of organic–inorganic lead halide perovskite thin films

2016 ◽  
Vol 4 (33) ◽  
pp. 7775-7782 ◽  
Author(s):  
Paul F. Ndione ◽  
Zhen Li ◽  
Kai Zhu
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Spectroscopic Ellipsometry ◽  
Optical Constants ◽  
Optical Transitions ◽  
Inorganic Perovskite ◽  
Inorganic Lead ◽  
Halide Perovskite ◽  
Lead Halide

Spectroscopic ellipsometry analysis of optical transitions and optical constants in hybrid organic–inorganic perovskite alloys.

Surface Modification of a-C:H(N) Thin Films by Plasma Treatment

2005 ◽  
Vol 11 (S03) ◽  
pp. 162-165 ◽  
Author(s):  
L. von Mühlen ◽  
R. A. Simao ◽  
C. A. Achete
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Optical Properties ◽  
Surface Modification ◽  
Surface Chemistry ◽  
Plasma Treatment ◽  
Surface Properties ◽  
Functional Groups ◽  
Material Properties ◽  
Modify Surface

Surface chemistry and topography of materials are generally preponderant factors in a series of material properties, such as adhesion, wettability, friction and optical properties [1]. Wettability of films, for example, can be altered significantly by modifying its surface roughness and also by incorporating functional groups. Plasma treatment is a powerful and versatile way to modify surface properties of amorphous nitrogen-incorporated carbon thin films (a-C:H(N)) and obtain materials with improved properties, once it is possible to modify the surfaces in a controlled way by specific settings of plasma conditions. [2 - 4]

Optical Properties of GaN Thin Films on Sapphire Substrates Characterized by Variable-Angle Spectroscopic Ellipsometry

1998 ◽  
Vol 37 (Part 2, No. 10A) ◽  
pp. L1105-L1108 ◽  
Author(s):  
Tao Yang ◽  
Shigeo Goto ◽  
Masahiko Kawata ◽  
Kenji Uchida ◽  
Atsuko Niwa ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Spectroscopic Ellipsometry ◽  
Sapphire Substrates ◽  
Variable Angle ◽  
Variable Angle Spectroscopic Ellipsometry

scholarly journals Growth of Atomic Layer Deposited Ruthenium and Its Optical Properties at Short Wavelengths Using Ru(EtCp)2 and Oxygen

Coatings ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 413 ◽  
Author(s):  
Robert Müller ◽  
Lilit Ghazaryan ◽  
Paul Schenk ◽  
Sabrina Wolleb ◽  
Vivek Beladiya ◽  
...  
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Optical Properties ◽  
Deposition Temperature ◽  
Film Growth ◽  
High Surface ◽  
Atomic Layer ◽  
Fused Silica ◽  
High Density ◽  
Adhesion Properties

High-density ruthenium (Ru) thin films were deposited using Ru(EtCp)2 (bis(ethylcyclopentadienyl)ruthenium) and oxygen by thermal atomic layer deposition (ALD) and compared to magnetron sputtered (MS) Ru coatings. The ALD Ru film growth and surface roughness show a significant temperature dependence. At temperatures below 200 °C, no deposition was observed on silicon and fused silica substrates. With increasing deposition temperature, the nucleation of Ru starts and leads eventually to fully closed, polycrystalline coatings. The formation of blisters starts at temperatures above 275 °C because of poor adhesion properties, which results in a high surface roughness. The optimum deposition temperature is 250 °C in our tool and leads to rather smooth film surfaces, with roughness values of approximately 3 nm. The ALD Ru thin films have similar morphology compared with MS coatings, e.g., hexagonal polycrystalline structure and high density. Discrepancies of the optical properties can be explained by the higher roughness of ALD films compared to MS coatings. To use ALD Ru for optical applications at short wavelengths (λ = 2–50 nm), further improvement of their film quality is required.

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