scholarly journals Determination of Dielectric Constant of Stearic Acid Films Using Varying Gap Immersion Method

1977 ◽  
Vol 4 (1) ◽  
pp. 23-28 ◽  
Author(s):  
V. K. Agarwal ◽  
B. Ichijo
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Film Thickness ◽  
Stearic Acid ◽  
Reasonable Agreement ◽  
Langmuir Films ◽  
Immersion Method ◽  
Experimental Tool ◽  
High Degree

The dielectric constant data (at 3.5 MHz) on stearic acid thin films, obtained by using variable gap immersion method, are presented. Many of the errors of the conventional universal bridge method are eliminated in the method used here. It is also shown that the varying gap immersion method serves as an experimental tool for simultaneous determination of film thickness with high degree of accuracy. The data on evaporated as well as Langmuir films of stearic acid (≥1000 Å) are found to be consistent and in reasonable agreement.

scholarly journals Thickness-dependent electrocaloric effect in mixed-phase Pb 0.87 Ba 0.1 La 0.02 (Zr 0.6 Sn 0.33 Ti 0.07 )O 3 thin films

2016 ◽  
Vol 374 (2074) ◽  
pp. 20160056 ◽  
Author(s):  
T. M. Correia ◽  
Q. Zhang
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Phase Transitions ◽  
Film Thickness ◽  
Tetragonal Phase ◽  
Sol Gel ◽  
Breakdown Field ◽  
Electrocaloric Effect ◽  
Thickness Increase ◽  
Higher Temperature

Full-perovskite Pb 0.87 Ba 0.1 La 0.02 (Zr 0.6 Sn 0.33 Ti 0.07 )O 3 (PBLZST) thin films were fabricated by a sol–gel method. These revealed both rhombohedral and tetragonal phases, as opposed to the full-tetragonal phase previously reported in ceramics. The fractions of tetragonal and rhombohedral phases are found to be strongly dependent on film thickness. The fraction of tetragonal grains increases with increasing film thickness, as the substrate constraint throughout the film decreases with film thickness. The maximum of the dielectric constant ( ε m ) and the corresponding temperature ( T m ) are thickness-dependent and dictated by the fraction of rhombohedral and tetragonal phase, with ε m reaching a minimum at 400 nm and T m shifting to higher temperature with increasing thickness. With the thickness increase, the breakdown field decreases, but field-induced antiferroelectric–ferroelectric ( E AFE−FE ) and ferroelectric–antiferroelectric ( E FE−AFE ) switch fields increase. The electrocaloric effect increases with increasing film thickness. This article is part of the themed issue ‘Taking the temperature of phase transitions in cool materials’.

Determination of dielectric constant and loss of high-K thin films in the microwave frequencies

Measurement ◽  
2010 ◽  
Vol 43 (4) ◽  
pp. 556-562 ◽  
Author(s):  
K. Sudheendran ◽  
D. Pamu ◽  
M. Ghanashyam Krishna ◽  
K.C. James Raju
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Microwave Frequencies ◽  
Dielectric Constant And Loss ◽  
High K

Effects of substrate on determination of hardness of thin films by nanoscratch and nanoindentation techniques

2004 ◽  
Vol 19 (6) ◽  
pp. 1791-1802 ◽  
Author(s):  
Noureddine Tayebi ◽  
Andreas A. Polycarpou ◽  
Thomas F. Conry
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Elastic Recovery ◽  
Empirical Relationship ◽  
Residual Deformation ◽  
Substrate Effect ◽  
Nanoindentation Technique ◽  
Film Substrate ◽  
Composite Hardness

A comparative study on the effects of the substrate on the determination of hardness of thin films by the use of the nanoscratch and nanoindentation techniques was conducted. Gold films deposited on fused quartz substrates and silicon dioxide films deposited on aluminum substrates with variant film thicknesses were investigated. These two systems correspond to a soft film on a hard substrate and a hard film on a soft substrate, respectively. The effect of substrate interaction on the measurement of hardness using the nanoscratch technique was found to be less pronounced compared to that of the nanoindentation technique due to: (i) the lower normal loads applied to achieve the penetration depths that occur at higher loads when using the nanoindentation method; (ii) the direct imaging of the residual deformation profile that is used in the nanoscratch technique, which allows for the effects of pileup or sink-in to be taken into account, whereas in the nanoindentation technique the contact area is estimated from the load-displacement data, which does not include such effects; and (iii) the account of elastic recovery of the plastically deformed surfaces from scratch tests. The film thickness did not appear to have any effect on the hardness of Au and SiO2 films obtained from nanoscratch data. This observation allowed, for the case of SiO2 films, the determination of the “free substrate effect region” and the derivation of an empirical relationship that relates the composite hardness of the film/substrate system to the contact-depth-to-film-thickness ratio, even when the indenter penetrates into the substrate. Such findings can allow for the determination of the intrinsic hardness of ultrathin hard films (∼1–5 nm thick), where the substrate effect is unavoidable.

Dielectric constant measurements of thin films and liquids using terahertz metamaterials

RSC Advances ◽  
2016 ◽  
Vol 6 (73) ◽  
pp. 69381-69386 ◽  
Author(s):  
S. J. Park ◽  
S. A. N. Yoon ◽  
Y. H. Ahn
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Polymer Films ◽  
Dielectric Constants ◽  
Polar Liquids ◽  
Terahertz Metamaterials

In this paper, we demonstrate that terahertz (THz) metamaterials are powerful tools for determination of dielectric constants of polymer films and polar liquids.

A TEM study of microstructures of YBa2Cu3O7−x thin films deposited on LaAlO3 by laser ablation

1991 ◽  
Vol 6 (9) ◽  
pp. 1823-1828 ◽  
Author(s):  
S.N. Basu ◽  
A.H. Carim ◽  
T.E. Mitchell
Keyword(s):  
Thin Films ◽  
Laser Ablation ◽  
Film Thickness ◽  
Single Crystal ◽  
Grain Boundaries ◽  
Misfit Dislocations ◽  
High Angle ◽  
Interfacial Structures ◽  
High Degree ◽  
Periodic Spacing

The microstructures of YBa2Cu3O7−x thin films deposited by laser ablation on single crystal (001) LaAlO3 substrates have been investigated. The orientation of the YBa2Cu3O7−x layer next to the interface is found to be completely c-perpendicular, with a high degree of epitaxy between the film and the substrate. Misfit dislocations, with a periodic spacing of around 13 nm, are present at the interface. Two distinct interfacial structures are seen in these films. At a film thickness of around 400 nm, nucleation of c-parallel grains occurs, leading to a switchover from a c, and, and-perpendicular to a c-parallel microstructure. Amorphous particulates, ejected from the target during processing, lead to the formation of misoriented grains, giving rise to high-angle grain boundaries in the film.

scholarly journals Growth and Correlation of the Physical and Structural Properties of Hexagonal Nanocrystalline Nickel Oxide Thin Films with Film Thickness

Coatings ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 615 ◽  
Author(s):  
Hammad ◽  
Abdel-wahab ◽  
Vattamkandathil ◽  
Ansari
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Film Thickness ◽  
Nickel Oxide ◽  
Near Infrared ◽  
Nir Spectroscopy ◽  
Thickness Measurement ◽  
Hexagonal Structure ◽  
Oxide Thin Films ◽  
Nickel Oxide Thin Films

This study investigated nonstoichiometric nickel oxide thin films prepared via the DC-sputtering technique at different film thicknesses. The prepared films were characterized by a surface profiler for thickness measurement, X-ray diffraction (XRD) for film nature, atomic force microscopy (AFM) for film morphology and roughness, UV-visible-near infrared (UV-vis.-NIR) spectroscopy for optical transmittance spectra of the films, and the photoluminescence (PL) spectra of the prepared films were obtained. The measured film thickness increased from 150 to 503 nm as the deposition time increased. XRD detected the trigonal crystal system of NiO0.96. The crystallite sizes were mainly grown through (101) and (110) characteristic planes. NiO0.96 films have a spherical particle shape and their sizes decreases as the film thickness increased. The optical band gap values decrease from 3.817 to 3.663 eV when the film thickness increases. The refractive index was estimated from the Moss relation, while the high-frequency dielectric constant and the static dielectric constant were deduced from the empirical Adachi formula. The photoluminescence behavior of the studied films confirmed the photogeneration of an electron-hole in nickel and oxygen vacancies. Hence, this study confirms the presence of nickel oxide lattice in the hexagonal structure containing the defects originated from the nickel vacancies or the excess of oxygen.

The Determination of Elemental Composition, Thickness and Crystalline Phases in Single and Multi-Layer Thin Films

1989 ◽  
Vol 33 ◽  
pp. 197-204
Author(s):  
R. A. Brown ◽  
K. Toda ◽  
R. L. Wilson
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Film Thickness ◽  
Elemental Composition ◽  
Crystalline Phases ◽  
Film Composition ◽  
Layer Thin Film

The purpose of this paper is to show how XRD and XRF can be used as complimentary tools to determine multi-layer thin film composition, both elemental and crystalline, as well as film thickness.

Nanoporous Silica for Low k Dielectrics

1996 ◽  
Vol 443 ◽  
Author(s):  
Teresa Ramos ◽  
Kevin Roderick ◽  
Alok Maskara ◽  
Douglas M. Smith
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Film Thickness ◽  
Pore Size ◽  
Ambient Pressure ◽  
Porous Solids ◽  
Nanoporous Silica ◽  
Low Density ◽  
Trade Offs ◽  
Small Pore

AbstractConsiderable progress has been made in development of thin films of nanoporous silica (also known as aerogels or low density xerogels) for ILD and IMD applications. Advantages of these materials include high thermal stability, small pore size, and similarity to conventional deposition processes, precursors and final material (silica). We have previously reported success in synthesizing low density, low dielectric constant (K<2) thin films using ambient pressure processing. However, processing of those films was complicated due to large number of process steps and difficulties in independently controlling both film thickness and film porosity.Nanoglass has now developed a new process which considerably reduces the number of process steps and allows independent control of both film thickness and porosity. The dielectric constant of the films can be tailored between 1.3 and 2.5. These films have improved mechanical properties due to controlled pore size and narrow pore size distribution and also because of higher density. The trade-offs between density, mechanical strength and dielectric constant for these types of porous solids will be elucidated. The known properties of the film and the process flow for deposition and post-deposition curing and the role of the relative rates of reaction, gelation, aging, and drying will be presented.

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