Fabrication and Dielectric Characterization of a Novel Polyimide

2013 ◽  
Vol 395-396 ◽  
pp. 29-32
Author(s):  
Jia Qi Lin ◽  
Pan Pan Zhang ◽  
Wen Long Yang
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Loss Tangent ◽  
Pyromellitic Dianhydride ◽  
Dielectric Spectra ◽  
Dielectric Characterization

A novel polyimide (PI) films with three kinds of monomers was synthesized in this paper. The polyimide unit is derived from Pyromellitic dianhydride (PMDA), 3,3',4,4'-benzophenonetetracarboxylic dianhydride, (BTDA), and 4,4, -diaminodiphenyl ether (ODA). The dielectric properties of the films were measured. The dielectric spectra show that dielectric constant is about 3.7, which is larger than the PI with two kinds of monomers. In addition, the loss tangent and conductivity of the films is quite small, which is important for the practical use of them.

Bulk and In-Circuit Dielectric Characterization of LTCC Tape Systems Through Millimeter Wave Frequency Range

2011 ◽  
Vol 2011 (1) ◽  
pp. 000740-000746 ◽  
Author(s):  
Bradley Thrasher ◽  
Deepukumar Nair ◽  
James Parisi ◽  
Glenn Oliver ◽  
Michael A. Smith
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Millimeter Wave ◽  
Design Stage ◽  
Frequency Range ◽  
Dielectric Thickness ◽  
Dielectric Characterization ◽  
Wide Range ◽  
Comprehensive Characterization

Low Temperature Co-fired Ceramic (LTCC) material systems offer a highly versatile microwave and millimeter wave packaging platform. Extremely low microwave loss, excellent control of dielectric constant, uniform dielectric thickness, non-existent water absorption leading to very high hermeticity, ability to support multilayer structure leading to 3-dimensional packaging, ability to embed passive functions within the tape layers, availability of a wide range of metallizations, etc. are some of the key advantages of LTCC for microwave packaging. One of the important parameters which needs to be determined at the very early stages of circuit designs are the dielectric properties - dielectric constant and loss tangent, both of which are functions of frequency. These properties need to be known accurately over the entire frequency range of operation for the circuit. For LTCC based designs, the use of dielectric constant of bulk material can lead to deviations between the performance expected at the design stage and for the fabricated circuit. Such deviations are a significant concern for broadband circuits as well as for circuits with sharp resonant behavior such as filters. One of the significant sources of deviation between bulk LTCC and “in-circuit” dielectric constant is the nature of the thick film metallizations used in LTCC technology. Work described here is a comprehensive characterization of three DuPont™ GreenTape™ LTCC systems 951, 943, and 9K7 - in the frequency range 10 to 70 GHz. Both bulk and “in-circuit” dielectric properties with silver and gold metallizations are studied to quantify the deviations in dielectric properties. A Fabry-Perot open resonator technique is used for the bulk characterization while printed ring resonators are used for the in-circuit characterization. This comprehensive characterization will provide key design data for LTCC designers in the 10 – 70 GHz frequency range.

Dielectric Constant and Loss Tangent Characterization of Thin High-K Dielectrics Using Corner-to-Corner Plane Probing

2006 ◽  
Author(s):  
A. Ege Engin ◽  
Abdemanaf Tambawala ◽  
Madhavan Swaminathan ◽  
Swapan Bhattacharya ◽  
Pranabes Pramanik ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Loss Tangent ◽  
Dielectric Constant And Loss ◽  
High K

Dielectric Characterization of Polyceram Films

1990 ◽  
Vol 180 ◽  
Author(s):  
G. Teowee ◽  
J.M. Boulton ◽  
H.H. Fox ◽  
A. Koussa ◽  
T. Gudgel ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Polyethylene Oxide ◽  
Dielectric Materials ◽  
Inorganic Materials ◽  
Functionalized Polymers ◽  
Multifunctional Materials ◽  
Dielectric Characterization ◽  
Silicon Alkoxides ◽  
Tan Δ

ABSTRACTPolycerams are an emergent class of hybrid, multifunctional materials which combine the properties of organic and inorganic materials. Films have been prepared from silicon alkoxides and reactive, functionalized polymers such as triethoxysilyl modified polybutadiene (MPBD), (N-triethoxysilylpropyl)O polyethylene oxide urethane (MPEOU) and trimethoxysilylpropyl substituted polyethyleneimine (MPEI). Characterization of dielectric constant and tan δ of the films has been carried out over a range of frequency from 500 Hz to 100 kHz; and the results are used to consider the potential of Polycerams as dielectric materials.

Broadband Dielectric Characterization of Aluminum Oxide (Al2O3)

2008 ◽  
Vol 5 (1) ◽  
pp. 2-7 ◽  
Author(s):  
Khalid Z. Rajab ◽  
Mira Naftaly ◽  
Edmund H. Linfield ◽  
Juan C. Nino ◽  
Daniel Arenas ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Aluminum Oxide ◽  
Time Domain ◽  
Measurement Techniques ◽  
Thz Spectroscopy ◽  
Dielectric Characterization ◽  
Dielectric Constant And Loss ◽  
Ir Frequencies ◽  
Cofired Ceramics

Applications for low-temperature cofired ceramics (LTCC) and high-temperature cofired ceramics (HTCC) are advancing to higher frequencies. In order to design ceramic microsystems and electronic packages, the electrical properties of materials must be well characterized over a broad frequency range. In this study, the dielectric properties of commercial aluminum oxide (Al2O3) with different glass loadings are characterized using three different measurement techniques: the split-post cavity, terahertz (THz) time-domain spectroscopy, and Fourier transform IR spectroscopy (FTIR). Specifically, the dielectric properties will be characterized from 10 GHz to IR frequencies. A split-post cavity was employed for determination of dielectric properties in the 10 GHz range. A broadband THz spectroscopy technique was used to characterize the specimens using measured time-domain transmission data. The dielectric constant and loss were extracted from the sample's frequency-domain transmission characteristics, providing data between 100 GHz and 2 THz. Additionally, FTIR was used to characterize the samples from ~33 to 3300 cm−1 (~1–100 THz). The measurements from the three techniques are compared, and dielectric constant and loss data will be presented for commercial and experimental ceramic systems from 10 GHz to IR frequencies.

Synthesis and Characteristics of MgO Coated BST-Mg2TiO4 Composite Ceramics

2012 ◽  
Vol 512-515 ◽  
pp. 1180-1183
Author(s):  
Qian Qian Jia ◽  
Hui Ming Ji ◽  
Shan Liu ◽  
Xiao Lei Li ◽  
Zheng Guo Jin
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Curie Temperature ◽  
Loss Tangent ◽  
Phase Shifters ◽  
Precipitation Method ◽  
Composite Ceramics ◽  
Low Dielectric ◽  
Dielectric Constant And Loss ◽  
Bst Ceramics

The (Ba, Sr)TiO3 (hereafter BST) ceramics are promising candidate for applying in tunable devices. MgO coated BST-Mg2TiO4 (BSTM-MT) composite ceramics were prepared to obtain the low dielectric constant, low dielectric loss, good dielectric constant temperature stability, and high tunability of BST ceramics. The Ba0.55Sr0.40Ca0.05TiO3 nanoparticles were coated with MgO using the precipitation method and then mixed with Mg2TiO4 powders to fabricate BSTM-MT composite ceramics. The morphologies, phases, elements, and dielectric properties of the sintered ceramics were investigated. The core-shell structure of BST powder wrapped with MgO was clearly observed from the TEM image. After sintered at 1100 °C for 2 h, the composite ceramics expressed dense microstructures from SEM images and two main phases BST and Mg2TiO4 were detected in the XRD patterns. The dielectric constant and loss tangent were both reduced after the coating. The reduced dielectric constant and loss tangent of BSTM-MT were 190, 0.0011 (2MHz), respectively. The ceramics exhibited the diffuse phase transition near the Curie temperature and the Curie temperature shifted from 10 °C to 5 °C after the coating. Since the continuous Ti-O bonds were disconnected with the MgO coating, the tunability was reduced to 15.14 % under a DC bias field of 1.1 kV/mm. The optimistic dielectric properties made it useful for the application of tunable capacitors and phase shifters.

scholarly journals Development of a Microfluidic GHz Impedance Cytometer

2013 ◽  
Vol 80 (12) ◽  
Author(s):  
Niels Haandbæk ◽  
Sebastian C. Bürgel ◽  
Flavio Heer ◽  
Andreas Hierlemann
Keyword(s):  
Dielectric Properties ◽  
Chinese Hamster Ovary ◽  
Cho Cells ◽  
Single Cells ◽  
Chinese Hamster ◽  
Frequency Range ◽  
Cell Nuclei ◽  
Dielectric Characterization ◽  
The Difference

AbstractThis article presents a novel microfluidic impedance cytometer enabling dielectric characterization of single cells at frequencies up to 500 MHz. The dielectric properties of cells at lower frequencies contain information about their size and membrane capacitance. The increased frequency range of the presented cytometer potentially allows for characterization of intracellular components, such as vacuoles or the cell nuclei. We demonstrate the overall capabilities of the cytometer through discrimination of polystyrene beads from Chinese hamster ovary (CHO) cells. The discrimination is based on the difference in dielectric properties at frequencies up to 500 MHz.

Effect of Platinum Substitution on the Microstructures and Dielectric Relaxation of CaCu3Ti4O12 Ceramics

2013 ◽  
Vol 802 ◽  
pp. 134-138 ◽  
Author(s):  
Worawut Makcharoen
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Loss Tangent ◽  
Room Temperature ◽  
High Dielectric Constant ◽  
Ferroelectric Materials ◽  
X Ray Diffraction ◽  
High Loss ◽  
Internal Barrier Layer Capacitor ◽  
High Dielectric

The CaCu3Ti4O12(CCTO) has the advantage for the various applications especially for capacitive elements in microelectronic devices over the ferroelectric materials including BaTiO3. CCTO is a ceramic compound with a high dielectric constant but it has a high loss tangent at room temperature. In this work, the Influences of PtO2doping on the dielectric properties of CaCu3Ti4O12(CCTO) ceramics were investigate. The ceramics CCTO and PtO2doping CCTO were studied by X- ray diffraction, scanning electron microscopy. The dielectric properties have been measured as a function of temperature and frequency range 0.1 - 500 kHz. The XRD shows the CCTO structure does not changes after doping with platinum. The results show that PtO2doped can reduce the mean grain sizes of CCTO, but the dielectric constant still remained a height. The samples of 2.0 mol% Pt-doped have exhibited high dielectric constant of about 22,000 and the loss tangent about 0.7 at room temperature and frequency at 10 kHz. The reduced of the loss tangent could be interpreted with the internal barrier layer capacitor model (IBLC)

scholarly journals Dielectric properties of zinc sulfide concentrate during the roasting at microwave frequencies

2017 ◽  
Author(s):  
Guangjun He ◽  
Shiwei Li ◽  
Kun Yang ◽  
Jian Liu ◽  
Peng Liu ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Dielectric Loss ◽  
Zinc Sulfide ◽  
Apparent Density ◽  
Loss Tangent ◽  
Loss Factor ◽  
Microwave Energy ◽  
Dielectric Loss Factor ◽  
Sulfide Concentrate

Microwave technology has a potential application in the extraction of zinc from sulphide ores, knowledge of the dielectric properties of these ores plays a major role in the microwave design and simulation for any process. The dielectric properties of zinc sulfide concentrate for two different apparent densities—1.54 and 1.63 g/cm3—have been measured by using the resonance cavity perturbation technique at 915 and 2450 MHz during the roasting process for the temperature ranging from room temperature to 850 °C. The variations of dielectric constant, the dielectric loss factor, the dielectric loss tangent and the penetration depth with the temperature, frequency and apparent density have been investigated numerically. The results indicate that the dielectric constant increases as the temperature increases and temperature has a pivotal effect on the dielectric constant, while the dielectric loss factor has a complicated change and all of the temperature, frequency and apparent density have a significant impact to dielectric loss factor. Zinc sulfide concentrate is high loss material from 450 to 800 °C on the basis of theoretical analyses of dielectric loss tangent and penetration depth, its ability of absorbing microwave energy would be enhanced by increasing the apparent density as well. The experimental results also have proved that zinc sulfide concentrate is easy to be heated by microwave energy from 450 to 800 °C. In addition, the experimental date of dielectric constant and loss factor can be fitted perfectly by Boltzmann model and Gauss model, respectively.

scholarly journals Dielectric, Thermal and FTIR Studies of Cobalt Doped Magnesium Hydrogen Maleate Hexahydrate Single Crystals

2011 ◽  
Vol 8 (1) ◽  
pp. 91-96
Author(s):  
B. Rajagopal ◽  
M. V. Ramana ◽  
A. V. Sarma
Keyword(s):  
Activation Energy ◽  
Dielectric Constant ◽  
Dielectric Properties ◽  
Melting Point ◽  
Transition Metal ◽  
Single Crystals ◽  
Loss Tangent ◽  
Transition Metal Ions ◽  
Ftir Studies ◽  
First Time

Present work reports the dielectric, thermal and FTIR studies of Co2+: MHMH single crystal for the first time. The influence of addition of transition metal ions on the dielectric properties, like dielectric constant, loss tangent,a.c. conductivity and activation energy of these crystals was discussed. FTIR studies confirm the presence of carboxylate ions. The melting point of the sample and final product after decomposition are studied using TG/DTA.

Dielectric Properties and Microwave Heating Characteristics of Sodium Chloride at 2.45 GHz

2013 ◽  
Vol 32 (6) ◽  
pp. 587-596 ◽  
Author(s):  
Chenhui Liu ◽  
Libo Zhang ◽  
Jinhui Peng ◽  
Wenwen Qu ◽  
Bingguo Liu ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Sodium Chloride ◽  
Moisture Content ◽  
Penetration Depth ◽  
Loss Tangent ◽  
Loss Factor ◽  
Dielectric Measurement ◽  
Linear Functions ◽  
Microwave Drying

AbstractThe effects of moisture content and temperature on the dielectric property of sodium chloride were investigated by using open-ended senor dielectric measurement system at the frequency of 2.45 GHz. Moisture content is a major influencing factor in the variation of dielectric properties. Dielectric constant, loss factor and loss tangent all increase linearly with moisture content increasing. Three predictive models were developed to obtain dielectric constant, loss factor, loss tangent and of sodium chloride as linear functions of moisture content. Temperature between 20 °C and 100 °C has a positive effect on dielectric constant and loss factor. Penetration depth decreased nonlinearly with moisture and temperature increasing. A predictive model was developed to calculate penetration depth for sodium chloride as a fifth function of moisture content. In addition, the measurements indicate that the particles temperature increases linearly with microwaving heating time at different power levels. The knowledge gained from these results is useful in developing more effective applications of microwave drying and designing better sensors for measuring moisture content of sodium chloride.

Sign in / Sign up

Export Citation Format

Share Document