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This paper aims to focus on the evaluation of the electrical properties of bio-based polyurethane material derived from cashew nut husk tannin and also the effect of temperature and frequency on the dielectric values and alternate current (AC) conductivity.

Bio-based polyurethane is prepared from cashew nut husk tannin as polyol, their dielectric constant and dielectric loss factor are measured using an inductance capacitance resistance (LCR) metre, and the AC conductivity is determined using dielectric constant and loss values.

The dielectric constant values are high, and the values decrease with an increase in frequency but increase with an increase in temperature. The AC conductivity values are low; hence, the material can be categorized as insulators or semi-conductors. Because the polyurethanes have a good dielectric value and are cost-effective, as they are derived from renewable biomaterial waste, they have promising applications for the future.

The experiment is carried out up to the frequency of 200 KHz because of the limitation in the instrument. But for the institute of printed circuits (IPC) and other specifications, the values of dielectric loss and dielectric constant will be generally coated for 1 MHz.

The high dielectric constant and loss values show that the polyurethane can be opted for use as capacitors in electronic devices, and the values are comparable to the requirements of IPC4101A/24IPC; hence, they are suitable for the application as printed circuit board (PCB) laminate.

The use of biomaterial waste in the production of polyurethane will bring down the dependence of polyurethane industry on fossil fuel reserve, reduce carbon dioxide foot print and reduce the cost of production.

The motivation of the work was its ecological aspect and also aims on the use of an alternative bio-based material in the PCB industry.

Multichip modules provide short chip‐to‐chip interconnects in order to take advantage of the high speeds available in integrated circuits. One multichip approach utilises layers of embedded microstrip. In order to achieve the highest possible speed, it is necessary to use metals and dielectrics which have low relative dielectric constants and low loss. Polymer and polyimide dielectric materials hold great promise in MCM applications; however, their high frequency characteristics are often not well known. Since thin film dielectric properties may differ from the bulk properties, it is important to be able to determine the dielectric properties using on‐wafer measurement techniques rather than more conventional techniques. This paper focuses on some of the techniques available and discusses the advantages and shortcomings of different techniques for measuring dielectric properties.

In this paper we present new measured loss tangent data for commercially available substrates, and these data are supported by simulations that show how practical variations in loss tangent affect the performance of microwave interconnections and devices. The paper reviews the measurement techniques that are currently available to measure the dielectric constant and loss tangent of substrate materials, and includes a new variation on an existing method that enables substrate parameters to be more easily measured but retains high accuracy. Simulations have been performed on microstrip lines fabricated on 10mil thick substrates using gold conductors to show the relative contributions of conductor and dielectric loss to the total line loss over the frequency range 0‐40GHz. Included in these simulations are the effects of conductor surface roughness. The simulated data are related to measured line microstrip line loss data over the frequency range 50MHz‐40GHz. The measured values, for an etched gold line on alumina, vary from 0.0045dB/mm at 50MHz to 0.04dB/mm at 40GHz.

Thick film technology has been widely used in the past for medium performance packaging solutions, but has been unable to compete with thin‐film technology for high performance requirements. The problems of poor geometrical resolution, together with high dielectric constant and loss, have all contributed to the very limited adopting of thick‐film for advanced applications such as MCMs and microwave. This paper describes a new advanced ceramic based technology using thick‐film conductors and dielectric. Results showing the excellent geometrical properties which result from a combination of novel materials and processing, giving line widths down to 10 microns and via dimensions of 25 micron are presented. The novel dielectric material also provides a dielectric constant of 4, with a loss factor of 1 × 10^−4. This technology allows the fabrication of high density circuits and packages, offering many packaging solutions, including MCM, microwave, sensors and displays, all on one substrate.

There has been increasing interest in the development of printable electronics to meet the growing demand for low‐cost, large‐area, miniaturized, flexible and lightweight devices. The purpose of this paper is to discuss the electronic applications of novel printable materials.

The paper addresses the utilization of polymer nanocomposites as it relates to printable and flexible technology for electronic packaging. Printable technology such as screen‐printing, ink‐jet printing, and microcontact printing provides a fully additive, non‐contacting deposition method that is suitable for flexible production.

A variety of printable nanomaterials for electronic packaging have been developed. This includes nanocapacitors and resistors as embedded passives, nanolaser materials, optical materials, etc. Materials can provide high‐capacitance densities, ranging from 5 to 25 nF/in², depending on composition, particle size, and film thickness. The electrical properties of capacitors fabricated from BaTiO₃‐epoxy nanocomposites showed a stable dielectric constant and low loss over a frequency range from 1 to 1,000 MHz. A variety of printable discrete resistors with different sheet resistances, ranging from ohm to Mohm, processed on large panels (19.5×24 inches) have been fabricated. Low‐resistivity materials, with volume resistivity in the range of 10⁻⁴‐10⁻⁶ ohm cm, depending on composition, particle size, and loading, can be used as conductive joints for high‐frequency and high‐density interconnect applications. Thermosetting polymers modified with ceramics or organics can produce low k and lower loss dielectrics. Reliability of the materials was ascertained by (Infrared; IR‐reflow), thermal cycling, pressure cooker test (PCT) and solder shock testing. The change in capacitance after 3× IR‐reflow and after 1,000 cycles of deep thermal cycling between −55°C and +125°C was within 5 per cent. Most of the materials in the test vehicle were stable after IR‐reflow, PCT, and solder shock.

The electronic applications of printable, high‐performance nanocomposite materials such as adhesives (both conductive and non‐conductive), interlayer dielectrics (low‐k, low‐loss dielectrics), embedded passives (capacitors and resistors), and circuits, etc.. are discussed. Also addressed are investigations of printable optically/magnetically active nanocomposite and polymeric materials for fabrication of devices such as inductors, embedded lasers, and optical interconnects.

A thin film printable technology was developed to manufacture large‐area microelectronics with embedded passives, Z‐interconnects and optical waveguides, etc. The overall approach lends itself to package miniaturization because multiple materials and devices can be printed in the same layer to increase functionality.

A review of the dielectric measurement techniques that are currently available for the characterization of thick film and LTCC materials at microwave and millimeter wave frequencies is presented. The intention is to show the relative advantages and limitations of the various methods, and to provide some practical guide to the particular technique that is most suitable for a given type of material, for use in a particular application. In addition, a novel slit cavity resonator method is proposed to enable substrate parameters to be more easily measured, whilst retaining high measurement accuracy. Measured data on materials from a variety of manufacturers are presented to show the validity and usefulness of this method.

The purpose of this paper is to create multilayer substrate (composite) from various low temperature co-fired ceramic (LTCC) substrates by their mutual combinations and to analyse influence of these multilayer substrates on dielectric properties in GHz frequency range.

GreenTape 951, GreenTape 9K7 and Murata LFC were used to create compound multilayer substrates that include three layers: middle layer is from Murata LFC, and both upper and bottom layers are either from GreenTape 951 or GreenTape 9K7. Shrinkage in all x-, y- and z-axes of all substrates including multilayer substrates were analysed, and influence of different shrinkage on dielectric properties was examined by microstrip ring resonators applied on all mentioned of substrates.

The middle layer of Murata LFC has significant influence on shrinkage value of composites which has a good repeatability and minimalizes problems with design of multilayer LTCC devices. Impact of middle layer from Murata LFC on dielectric constant is not significant, but on the other hand Q factor (loss tangent) of these composites is increased according to inhomogeneity between single LTCC layers, especially at frequency around 6 GHz.

The novelty of this work lies in creating multilayers systems from different types of LTCC substrates to find combination with the most suitable physical and dielectric properties for various purposes in GHz range applications.

Epoxy resin (EP) is a kind of thermosetting resin, and its application is usually limited by poor toughness. In this case, a type of new flexible chain blocking hyperbranched polyester (HBP) was designed and synthesized. The purpose of this study is to enhance the toughness and dielectric properties of EP.

P-toluene sulfonic acid was used as the catalyst, with dimethy propionic acid as the branch unit and pentaerythritol as the core in the experiment. Then, n-hexanoic acid and n-caprylic acid were, respectively, put to gain HBP with a n-hexanoic acid and n-caprylic acid capped structure. The microstructure, mechanical properties, insulation properties and dielectric properties of the composite were characterized for the purpose of finding the appropriate proportion of HBP.

HBP enhanced the toughness of epoxy-cured products by interpenetrating polymer network structure between the flexible chain of HBP and the EP molecular chain. Meanwhile, HBP reduced the ε and tgδ of the epoxy anhydride-cured product by reducing the number of polar groups per unit volume of the EP through free volumes.

Yet EP is a kind of thermosetting resin, which is widely used in coating, aerospace, electronics, polymer composites and military fields, but it is usually limited by poor toughness. In a word, it is an urgent priority to develop new EP with better toughness and mechanical properties.

At present, HBP has been applied as a new kind of toughening strategy and as a modifier for EP. According to the toughening mechanism of HBP modified EP, the free volume of HBP creates a space for the EP molecule to move around when loaded. Moreover, the free volume could cause the dielectric constant of EP to diminish by reducing the content of polarizable groups. Meanwhile, the addition of HBP with flexible chains grafted to the EP could develop an interpenetrating network structure, thus further enhancing the toughness of EP

The evolution of digital electronic systems to ever‐faster pulse rise times has placed increased demands on printed wiring board (PWB) materials. Signal loss associated with dielectric materials has driven development and commercialization of cost‐effective low loss laminate materials. In order to provide a better understanding of conductor material and surface finish choices, efforts have been made to quantify the impacts of these factors on loss. An alternative test approach has been identified which provides a measure of conductor performance, decoupled from both system geometry and the influence of laminate material.

The purpose of this study is to investigate the effect of the considerable Ag₂SO₄ content on the electrical and dielectric properties of (AgPO₃)_1−x(Ag₂SO₄)_x ion glass system as well as to extract thermodynamic parameters.

Glass samples of (AgPO₃)_1-x(Ag₂SO₄)_x with different mole ratios of Ag₂SO₄ [x = 0.00, 0.10,0.15,0.20 and 0.25] have been synthesized and used. X-ray diffraction and differential thermal analysis were used to investigate structural and thermal properties, and then the electrical characterizations of the bulk glasses were performed in different frequency and temperature range.

For different ratios of Ag₂SO₄ on AgPO₃, the bulk conductivity is enhanced with increasing the amount of Ag₂SO₄ until the composition of x = 0.20, after which the conductivity decreases. The general behavior of both ε’ and ε” decreases with increasing frequency and increases with increasing temperature. Complex impedance analysis studied by Z‘−Z’ and Cole–Cole plot at different temperatures revealed that bulk resistance decreases with temperature.

The calculated values of activation free energy, enthalpy and entropy change for different compositions of (AgPO₃)_1-x(Ag₂SO₄)_x showed an increase in activation energy and enthalpy when Ag₂SO₄ ratio is increased in (AgPO₃)_1-x(Ag₂SO₄)_x composition up to 20%, and then there is a decrease in their values at x = 25%, which may be explained based on non-bridging oxygen.