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.

Epitaxial Growth and Anisotropic Dielectric Properties of La-Doped Bi4Ti3O12 Thin Films

2007 ◽  
Vol 124-126 ◽  
pp. 177-180
Author(s):  
Jang Sik Lee ◽  
Q.X. Jia
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Dielectric Properties ◽  
Bottom Electrode ◽  
Dielectric Constants ◽  
The Other ◽  
Field Range ◽  
Anisotropic Dielectric ◽  
Dielectric Nonlinearity ◽  
La Doped

To investigate the anisotropic dielectric properties of layer-structured bismuth-based ferroelectrics along different crystal directions, we fabricate devices along different crystal orientations using highly c-axis oriented Bi3.25La0.75Ti3O12 (BLT) thin films on (001) LaAlO3 (LAO) substrates. Experimental results have shown that the dielectric properties of the BLT films are highly anisotropic along different crystal directions. The dielectric constants (1MHz at 300 K) are 358 and 160 along [100] and [110], respectively. Dielectric nonlinearity is also detected along these crystal directions. On the other hand, a much smaller dielectric constant and no detectable dielectric nonlinearity in a field range of 0-200 kV/cm are observed for films along [001] when c-axis oriented SRO is used as the bottom electrode.

scholarly journals On the measurement of the dielectric constants of liquids, with a determination of the dielectric constant of benzene

1929 ◽  
Vol 123 (792) ◽  
pp. 664-685 ◽  
Keyword(s):  
Dielectric Constant ◽  
Physical Properties ◽  
Dielectric Constants ◽  
Experimental Conditions ◽  
The Past ◽  
A Value ◽  
The Subject ◽  
Important Indication

It has long been recognised that the dielectric constant of a substance gives an important indication of its constitution, and the classical papers of Nernst and Drude giving methods for the determination of dielectric constants, have been followed by a long series of papers giving the dielectric constants of several hundreds of pure liquids and solutions. Since the publication of Debye’s dipole theory in 1912, the literature of the subject has become even more voluminous than before. In surveying the mass of data one is struck by the very large discrepancies which exist in the values obtained by different observers for any one substance, and it is very difficult to decide whether they are due to the difficulty of pre­paring and purifying the substance, differences in experimental conditions such as frequency of the applied E. M. F., or errors in the methods of measure­ment. In order to make it possible to compare the results of different observers, and to provide a fundamental basis for new measurements, it is important that the value of at least one standard liquid should be known with unquestion­able accuracy. The object of the present investigation was to provide such a value. Benzene was chosen as the standard liquid since it has been very widely used in the past, and it is used as a standard in the measurement of other physical properties.

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

Dielectric Property of PZT Thin Films Doped with PMnN

2012 ◽  
Vol 569 ◽  
pp. 35-38
Author(s):  
Tao Zhang ◽  
Min Li ◽  
Ting Liu ◽  
Bin Sun ◽  
Sheng Nan Zhou
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Dielectric Property ◽  
Quality Factor ◽  
Mechanical Quality Factor ◽  
Dielectric Constants ◽  
Pzt Thin Films ◽  
Testing Frequency ◽  
Mechanical Quality ◽  
Doping Ratio

The high piezoelectricity and high mechanical quality factor thin films are very important for the fabrications of micro devices. The Pb(Zrx,Ti1-x)O3(PZT) thin films own high piezoelectricity, however, its mechanical quality factor is small. The proper doping of Pb(Mn1/3,Nb2/3)O3(PMnN) will perfectly improve the mechanical quality of the films. However, the doping of PMnN will change the dielectric property of PZT thin films, and so it’s very necessary to investigate the dielectric property of PZT thin films doped with different ratio of PMnN. In this paper, the Pb(Mn1/3,Nb2/3)O3- PbZrO3-PbTiO3(PMnN-PZT) thin films with different doping ratio of PMnN are deposited by the magnetron sputtering method, and the X-ray diffraction is applied to analyze the structure of thin films, and the relative dielectric constant are characterized by the LCR testing system. The results show that the PMnN-PZT thin films with smaller doping ratio than 20% exhibit polycrstal structure, and the dielectric constant of thin films increase with the doping ratio of PMnN sharply, especially the doped PMnN is smaller than 6 mol percent. All the dielectric constants decrease with the testing frequency, and which have little change if the testing frequency is larger than 2.5kHz.

scholarly journals On the direct determination of the electrostatic moments of molecules

1929 ◽  
Vol 124 (795) ◽  
pp. 689-698 ◽  
Keyword(s):  
Dielectric Constant ◽  
Direct Determination ◽  
Negative Temperature ◽  
Dielectric Constants ◽  
Temperature Coefficients ◽  
Different Temperatures

According to Faraday's ideas, the specific inductive capacity of a substance is due to the polarisation of the molecules as wholes. This is the basis of the old Clausius-Mosotti theory of dielectrics, on which it is shown first that the polarisation P is proportional to the polarising field, i. e. , P = k E, k being the dielectric constant, and second that δ being the density of the dielectric, k - 2/ k + 2 ·1/δ = constant. Now it is known that some substances have large negative temperature coefficients for their dielectric constants which cannot thus be accounted for. To provide for this Debye proposed the theory that the molecules were permanently polarised and that they were systematically orientated in the field. This leads to the equation k - 2/ k + 2 = a T -1 + b T -2 , to represent the change of specific inductive capacity with temperature. This theory has been developed by Gans and others, and a number of measurements have been made by Smyth and others, who have found the molecular moments of many substances by measuring the dielectric constants at different temperatures.

Stiff Polyimides: Chain Orientation And Anisotropy Of The Optical And Dielectric Properties Of Thin Films

1991 ◽  
Vol 227 ◽  
Author(s):  
D. Boese ◽  
S. Herminghaus ◽  
D. Y. Yoon ◽  
J. D. Swalen ◽  
J. F. Rabolt
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Refractive Index ◽  
Dielectric Properties ◽  
Dielectric Constants ◽  
Polyimide Films ◽  
Lorenz Equation ◽  
Out Of Plane ◽  
Large Anisotropy ◽  
Uv Visible

ABSTRACTThin films of poly(p-phenylene biphenyltetracarboximide), prepared by thermal imidization of the precursor poly(amic acid) on substrates, have been investigated by optical waveguide, UV-visible, infrared (IR), and dielectric spectroscopies. The polyimide films exhibit an extraordinarily large anisotropy in the refractive indices with the in-plane index n║ = 1.852 and the out-of-plane index n┴ = 1.612 at 632.8 nm wavelength, indicating a strong preference of polymer chains to orient along the film plane. No discernible effect of the film thickness on this optical anisotropy is found in the range of ca. 0.4 μm to 7.8 μm in thickness. The frequency dispersion of the in-plane refractive index to 1.06 μm wavelength is consistent with the results calculated by the Lorentz-Lorenz equation from the UV-visible spectrum. The contribution from the entire IR range from 7000 to 200 cm,−1 computed by the Spitzer-Kleinmann dispersion relations from the measured spectra, adds ca. 0.07 to the in-plane refractive index n║. Approximately the same increase is assumed for the out-of-plane index n┴, based on the tilt-angle dependent IR results. Application of the Maxwell relation leads to the out-of-plane dielectric constant ε┴≃2.8 at ca. 1013 Hz, as compared with the measured value of ca. 3.0 at 106 Hz. Assuming this small difference to remain the same for the in-plane dielectric constants ε║, we obtain a a very large anisotropy in the dielectric properties of these polyimide films with the estimated in-plane dielectric constant ε║≃3.5 at ca. 1013 Hz, and ε.≃3.7 at 106 Hz.

scholarly journals An Empirical Relation for the Evaluation of the Dielectric Relaxation Time of Certain Polar Liquids Using a Single Microwave Frequency

1974 ◽  
Vol 27 (1) ◽  
pp. 87 ◽  
Author(s):  
BS Sarma ◽  
V Venkateswara Rao
Keyword(s):  
Experimental Data ◽  
Relaxation Time ◽  
Dielectric Relaxation ◽  
Concentration Factor ◽  
Empirical Relation ◽  
Microwave Frequency ◽  
Dielectric Constants ◽  
Dielectric Relaxation Time ◽  
Polar Liquids

An empirical relation is proposed for the determination of the dielectric relaxation time .. of polar liquids with nearly spherical molecules from measurements of the dielectric constants at a single microwave frequency. The relation is obtained by introducing a concentration factor as a parameter in the expression for .. derived by Eyring et al. (1941). Its validity for suitable polar liquids is demonstrated by comparison of results with previously reported values. Thermodynamic parameters for a number of liquids at various concentrations have also been evaluated from experimental data using the relation.

Sign in / Sign up

Export Citation Format

Share Document