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Article
Publication date: 20 January 2012

Shital Patil and Vijaya Puri

The purpose of this paper is to study properties of magnesium oxide and mixed magnesium oxide‐bismuth oxide thick films for application in tuned devices.

Abstract

Purpose

The purpose of this paper is to study properties of magnesium oxide and mixed magnesium oxide‐bismuth oxide thick films for application in tuned devices.

Design/methodology/approach

The effect of magnesium oxide and mixed magnesium oxide‐bismuth oxide thick films overlay of different thickness on Ag thick film microstrip rectangular patch antenna was investigated in the X band (8‐12 GHz). Using Ag thick film microstrip rectangular patch antenna the thick and mixed thick films was characterized by microwave properties such as resonance frequency, amplitude, bandwidth, quality factor and input impedance. Using the resonance frequency the permittivity of magnesium oxide and mixed magnesium oxide‐bismuth oxide thick films was measured.

Findings

Cubic structure of single magnesium oxide and monoclinic structure of bismuth oxide was present in mixed thick film. Also the morphology of single thick films was maintained in mixed thick film of magnesium oxide‐bismuth oxide. Due to overlay magnesium oxide and magnesium oxide‐bismuth oxide mixed thick films, change in resonance frequency shifts towards high frequency end was observed. Dielectric constant of magnesium oxide and mixed magnesium oxide‐bismuth oxide thick film calculated from resonance frequency decreased with increase in thickness.

Originality/value

The microwave properties using Ag thick film microstrip patch antenna due to overlay of magnesium oxide and mixed magnesium oxide‐bismuth oxide thick films have been reported for the first time. Thickness of overlay dependent tuning of the antenna has been achieved.

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Article
Publication date: 26 April 2013

S.N. Mathad, R.N. Jadhav and Vijaya Puri

The purpose of this paper was to determine the complex permittivity of bismuth strontium manganites (Bi1−xSrxMnO3) in the 8‐12 GHz range by using perturbation of Ag thick

Abstract

Purpose

The purpose of this paper was to determine the complex permittivity of bismuth strontium manganites (Bi1−xSrxMnO3) in the 8‐12 GHz range by using perturbation of Ag thick film microstrip ring resonator (MSRR) due to superstrate of both bulk and thick film.

Design/methodology/approach

The BSM ceramics were synthesized by simple low cost solid state reaction method and their fritless thick films were fabricated by screen printing technique on alumina substrate. A comparison has been made between the X band response of Ag thick film microstrip ring resonator due to perturbation of bulk and thick film Bi1−xSrxMnO3 ceramic.

Findings

The bulk and thick film superstrate decreases the resonance frequency of MSRR. In this technique even minor change in the properties of superstrate material changes the MSRR response. Variation of strontium content also influences microwave conductivity and penetration depth of bulk and thick films.

Originality/value

The microwave complex permittivity decreases with increase in Sr content in bismuth manganite and it is higher for bulk as compared to its thick films. The superstrate on Ag thick film microstrip ring resonator is an efficient tool capable of detecting the composition dependent changes in microwave properties of ceramic bulk and thick films.

Details

Microelectronics International, vol. 30 no. 2
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 1 April 2001

Sunit Rane and Vijaya Puri

In this paper studies on the lab formulated fritless silver thick film paste with two different binder compositions that have been used to fabricate λ/2 microstrip…

Abstract

In this paper studies on the lab formulated fritless silver thick film paste with two different binder compositions that have been used to fabricate λ/2 microstrip rejection filter in the X and Ku band are reported. These have been compared with ESL (USA) paste and copper thin film metallization for the same circuit. The thick film circuits were overlayed with TiO2 thick film of different thickness and changes in the characteristics studied. In the X band, the Q of the filter improves with overlay and is also dependent on the Ag paste formulation, whereas in the Ku band there are no thick film paste dependent properties observed due to overlay. Thickness of overlay and metallization paste formulation dependent factors should be taken into consideration during fabrication of high density and multi‐layer microwave integrated circuits.

Details

Microelectronics International, vol. 18 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

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Article
Publication date: 31 July 2007

U.B. Lonkar and Vijaya Puri

This paper aims to study tuning effects on thick film microstripline due to ferrite thick film overlay.

Abstract

Purpose

This paper aims to study tuning effects on thick film microstripline due to ferrite thick film overlay.

Design/methodology/approach

The possibility of obtaining tuning characteristics in the Ku band microwave region in the absence of external magnetic field by a simple process of using NixZn1−xFe2O4 thick film and bulk as in‐touch overlay over Ag thick film microstripline was investigated. The microstripline is basically a non‐resonant component with high‐transmission at a large microwave frequency band. The ferrite was synthesized by precursor method and the thick films were deposited by screen printing.

Findings

It was found that tuning characteristics were observed and composition, thickness and precursor dependent changes occurred. The changes with composition are more prominent in the 14.5‐16.5 GHz range. Also, the ferrite thick film overlay produces a deep notch at 15.7 GHz. It is observed that the pellet overlay also makes the microstripline very dispersive with a high‐insertion loss in the 16‐17 GHz range. The presence of permeability‐related effects interfering with the normal propagation of the microstrip circuits might be causing the changes in the circuits.

Originality/value

Owing to the NixZn1−xFe2O4 overlay the simple microstripline can be tuned to have narrow band filter type of characteristics. Thick film NixZn1−xFe2O4 overlay gives the added advantage of planer configuration along with cost‐effectiveness in the absence of magnetic field.

Details

Microelectronics International, vol. 24 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

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Article
Publication date: 5 May 2015

Busi Rambabu and Y. Srinivasa Rao

The purpose of this paper is to study high-voltage interactions in polymer thick-film resistors, namely, polyvinyl chloride (PVC)-graphite thick-film resistors, and their…

Abstract

Purpose

The purpose of this paper is to study high-voltage interactions in polymer thick-film resistors, namely, polyvinyl chloride (PVC)-graphite thick-film resistors, and their applications in universal trimming of these resistors.

Design/methodology/approach

The authors applied high voltages in the form of pulses and impulses of various pulse durations and with different amplitudes to polymer thick-film resistors and observed the variation of resistance of these resistors with high voltages.

Findings

The paper finds that high voltages can be used for trimming of polymer thick-film resistors in both directions, i.e. upwards and downwards.

Research limitations/implications

The research implication of this paper is that polymer thick-film resistors can be trimmed downwards or upwards practically using this method.

Practical implications

The practical implications of this paper is that one can trim the polymer thick-film resistors, namely, PVC–graphite thick-film resistors, in both directions, i.e. upwards and downwards, by using this method.

Originality/value

The value of the paper is in showing that high voltages can be used to trim downwards and also upwards in the case of polymer thick-film resistors. This type of trimming is called universal trimming, developed first time for polymer thick-film resistors.

Details

Microelectronics International, vol. 32 no. 2
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 1 January 1993

A. Dziedzic, J. Nijs and J. Szlufcik

Different techniques applied for the fabrication of thickfilm fine lines have been analysed. The basics, achievements, advantages and disadvantages of improved screen…

Abstract

Different techniques applied for the fabrication of thickfilm fine lines have been analysed. The basics, achievements, advantages and disadvantages of improved screen printing, screen printing with metal masks, the direct writing method, offset printing and photoformed or photoetched thickfilm are presented. In addition, current trends in front metallisation of silicon solar cells are described. Based on a critical review, the use of thickfilm fine lines for this purpose is discussed.

Details

Microelectronics International, vol. 10 no. 1
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 1 January 1987

R. Dell'Acqua

Thickfilm technology to implement passive elements, network and hybrid circuits has been widely used for four decades and its importance is still growing. While on one…

Abstract

Thickfilm technology to implement passive elements, network and hybrid circuits has been widely used for four decades and its importance is still growing. While on one hand the technology has been improved to meet the requirements for more sophisticated circuits, on the other hand a better knowledge of its outstanding properties has promoted its application to a certain number of sometimes exotic devices, many of which are in the sensor and actuator area. This paper presents examples of a variety of applications to illustrate what thick film technology can offer outside the familiar area, and to stimulate the imagination of scientists towards possible new applications.

Details

Microelectronics International, vol. 4 no. 1
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 1 February 1986

M.S. Setty

Thick film technology is increasingly used in hybrid microelectronic circuits throughout the world. It is entering areas of electronics hitherto dominated by other…

Abstract

Thick film technology is increasingly used in hybrid microelectronic circuits throughout the world. It is entering areas of electronics hitherto dominated by other technologies. Materials are the most important parameter in any technological development. A single material can generate several technologies (e.g., silicon). The role of a Materials Scientist, particularly in the case of Thick Film Materials, has to be very comprehensive. A ‘Vertical Integration System’ is followed in the study and development of thick film materials. This has helped in understanding the complex reactions taking place and in rectifying the defects formed during thick film processing. It has been amply rewarded during the development of several conducting and resistive materials and while carrying out the basic studies of other materials as thick films. Some future trends in this area have been suggested for adapting this fascinating thick film technology.

Details

Microelectronics International, vol. 3 no. 2
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 2 January 2007

O.S. Aleksić, B.M. Radojčić and R.M. Ramović

The paper aims to focus on thick film planar thermistors.

Abstract

Purpose

The paper aims to focus on thick film planar thermistors.

Design/methodology/approach

Thick film planar thermistors such as rectangular, sandwich, multilayer, segmented and interdigitated were printed of law temperature NTC paste called NTC 3K3 95/2 (Ei Iritel). Their resistivity was measured at room temperature as a function of volume resistivity variations due to electrode effect (diffusion of PdAg into NTC layer) and variation of geometrical parameters such as length l, width w, thickness d, number of segments n. The experimental data obtained were used in forming a model by the simple fitting procedure for counting diffusion effect on volume resistivity and resistivity dependence on geometrical parameters.

Findings

Thermal behavior of NTC thick films was measured in the range of −30‐120°C. Exponential factor B was fitted for measured values and included in the proposed thick film thermistors model. The agreement of measured and calculated data enables simulation of new thermistor geometries.

Originality/value

The paper focuses on the experiment which was the first step in forming a total physical/mathematical model proposed for thick film thermistor resistivity.

Details

Microelectronics International, vol. 24 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

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Article
Publication date: 1 March 1991

M. Lahdenperä

In this research work thickfilm manufacturing technology on stainless steel baseplates was developed. Adequate adhesion of dielectric IP211 to the steel substrate was…

Abstract

In this research work thickfilm manufacturing technology on stainless steel baseplates was developed. Adequate adhesion of dielectric IP211 to the steel substrate was achieved only by sand blast roughening. Standard PdAg thickfilm conductors were not solderable to IP211. The solution was to have a separate multilayer dielectric under conductors to be soldered. The reliability of soft soldering and gold wire bonding of thickfilm metallisation on stainless steel and other baseplate materials was evaluated. The technology developed was applied to manufacturing an intelligent signal node. Present expertise enables the manufacture of thickfilm hybrids on stainless steel baseplates. Development of an industrial production line would, however, involve considerable effort.

Details

Microelectronics International, vol. 8 no. 3
Type: Research Article
ISSN: 1356-5362

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