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Article
Publication date: 3 August 2015

Paweł Winiarski, Adam Kłossowicz, Jacek Wróblewski, Andrzej Dziedzic and Wojciech Stęplewski

The purpose of this paper is to characterize electrical properties of nickel-phosphorus (Ni-P) thin-film resistors made on FR-4 laminate in a wide range of temperature

Abstract

Purpose

The purpose of this paper is to characterize electrical properties of nickel-phosphorus (Ni-P) thin-film resistors made on FR-4 laminate in a wide range of temperature (from −180 to 20°C).

Design/methodology/approach

The study was performed using resistors made of Ni-P foil with two different thicknesses (0.1 or 0.05 μm) and sheet resistances (100 or 250 Ω/sq), respectively. The resistance rectangular resistors had length and width from the range between 0.59 and 5.91 mm. The resistance versus temperature characteristics and their distribution as well as resistors ' durability to low-temperature thermal shocks were investigated.

Findings

The results showed almost linear temperature dependence of resistance with a negative temperature coefficient of resistance of about −95 ppm/°C for 250 Ω/sq layer and −55 ppm/°C for 100 Ω/sq layer. A very small dimensional effect was observed for sheet resistance as well as for R(T) characteristic. Thin-film resistors are also characterized by very high durability to low-temperature thermal shocks.

Originality/value

The results presented in this paper can be very useful for low-temperature applications of thin-film resistors made on printed circuit boards. They suggest possibility of wide applications of these components in a wide temperature range.

Details

Circuit World, vol. 41 no. 3
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 7 August 2017

Wojciech Filipowski, Zbigniew Pruszowski, Krzysztof Waczynski, Piotr Kowalik and Jan Kulawik

The paper aims to present a research on the impact of the stabilization process of a thin metallic layer (Ni-P) produced on a ceramic surface (Al2O3) by means of

Abstract

Purpose

The paper aims to present a research on the impact of the stabilization process of a thin metallic layer (Ni-P) produced on a ceramic surface (Al2O3) by means of electroless metallization on its electric parameters and structure. On the basis of the research conducted, the existence of a relationship between resistance (R) and the temperature coefficient of resistance (TCR) of the test structure with a Ni-P alloy-based layer and the temperature of stabilization was proposed.

Design/methodology/approach

Metallic Ni-P layers were deposited on sensitized and activated substrates. Metallization was conducted in an aqueous solution containing two primary ingredients: sodium hypophosphite and nickel chloride. The concentration of both ingredients was (50-70) g/dm3. The process lasted 60 min, and the metallization bath pH was kept at 2.1-2.2, whereas the temperature was maintained at 363 K. The thermal stabilization process was conducted in different temperatures between 453 and 623 K. After the technological processes, the resistance and TCR of the test structures were measured with a micro ohmmeter. The composition and the morphology of the resistive layer of the structures examined was also determined.

Findings

The dependence of the resistance on the temperature of the stabilization process for the temperature range 553 to 623 K was described using mathematical relationships. The TCR of test resistors at the same thermal stabilization temperature range was also described using a mathematical equation. The measurements show that the resistive layer contains 82.01 at.% of nickel (Ni) and 17.99 at.% of phosphorus (P).

Originality/value

The results associate a surface morphology Ni-P alloy with the resistance and TCR according to temperature stabilization. The paper presents mathematical relationships that have not been described in the literature available.

Details

Microelectronics International, vol. 34 no. 3
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 24 April 2007

J. Kulawik, D. Szwagierczak, B. Gröger and A. Skwarek

The aim of the present work was the characterization of a group of compounds with the perovskite‐type structure in respect of their applicability as thermistor materials.

Abstract

Purpose

The aim of the present work was the characterization of a group of compounds with the perovskite‐type structure in respect of their applicability as thermistor materials.

Design/methodology/approach

Four compositions: La0.7Sr0.3Zr0.5Co0.22+Co0.33+O3, La0.8Sr0.2Ti0.5Co0.32+Co0.23+O3, La0.4Sr0.6Ti0.3Fe0.7O3 and CaTi0.8Co0.2O3 were synthesized by solid‐state reaction. Ceramic thermistor materials were sintered in the temperature range 1,300‐1,400°C. The synthesized powders were used for fabrication of thick film pastes and thermistors fired at 1,100‐1,250°C. Resistancetemperature characteristics of the ceramic samples were studied in the range −55 to 800°C for the ceramic samples and 20‐600°C for thick films. Endurance tests at 300°C for 500 h were performed.

Findings

The developed NTC materials exhibited high temperature coefficients of resistivity, dense microstructure and good stability. The most advantageous characteristics have been shown by La0.7Sr0.3Zr0.5Co0.22+Co0.33+O3 and La0.8Sr0.2Ti0.5Co0.32+Co0.23+O3 thermistors. The highest Temperature coefficient of resistances for the ceramics were found in the temperature range from −55 to 180°C (−10.7 to −2.9 per cent/°C) and for the thick films in the temperature range 40‐300°C (−5.6 to −1.5 per cent/°C).

Research limitations/implications

This work has been focused on preliminary choice of compositions appropriate for practical thermistor thick film applications. Elucidation of conduction mechanism of the investigated materials needs further complex studies of conductivity, nonstoichiometry, thermoelectric power, etc. as a function of temperature and oxygen partial pressure.

Originality/value

In this work, an attempt has been made to extend the typical range of NTC compositions and to fulfil the demand for improved stability of bulk and thick film thermistors at elevated temperatures.

Details

Microelectronics International, vol. 24 no. 2
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 1 January 1988

Y. Sorimachi, I. Tsubata and S. Miyauchi

A thick film overcurrent protector with self‐recovery has been developed using carbon black graft polymer. Carbon black graft polymer, henceforth called CG, is a thick…

Abstract

A thick film overcurrent protector with self‐recovery has been developed using carbon black graft polymer. Carbon black graft polymer, henceforth called CG, is a thick film PTC thermistor material in which a polymer forms a three‐dimensional network structure around carbon blacks by graft‐copolymerising vinyl monomers. Since the CG material gives a large and stable positive temperature coefficient of resistance depending on the copolymer material, due to the difference of thermal expansion coefficient between carbon blacks and polymer, the stable thick film overcurrent protector with self‐recovery can be realised by using the CG material. The overcurrent protector utilises the dynamic current‐time characteristics of the CG element. When a very large current flows through the CG element, the temperature rises by self‐heating, and the resistance of the element increases dramatically; as a result it restrains the current at a lower level. Since this element is not destroyed after excess current flow, it can be used repeatedly, unlike a metal fuse. In this paper, the manufacturing process and thermal and electrical characteristics of the CG overcurrent protector are investigated, including an analysis of these characteristics.

Details

Microelectronics International, vol. 5 no. 1
Type: Research Article
ISSN: 1356-5362

Content available
Article
Publication date: 16 July 2020

Tomasz Matusiak, Arkadiusz Dabrowski and Leszek Golonka

The purpose of this paper is to present the properties of thick-film resistors made of novel pastes prepared from glass and graphite.

Abstract

Purpose

The purpose of this paper is to present the properties of thick-film resistors made of novel pastes prepared from glass and graphite.

Design/methodology/approach

Graphite-based resistors were made of thick-film pastes with different graphite-to-glass mass fraction were prepared and examined. Sheet resistance, temperature coefficient of resistance, impact of humidity and short-term overload were investigated. The properties of the layers fired in atmospheres of air at 550°C and nitrogen at 875°C were compared.

Findings

Graphite-based resistors with various graphite-to-glass ratios made possible to obtain a wide range of sheet resistance from single O/square to few kO/square. These values were dependent on firing atmosphere, paste composition and the number of screen-printed layers. The samples made of paste with 1:1 graphite-to-glass ratio exhibited the temperature coefficient of resistance of about −1,000 ppm/°C, almost independently on the firing atmosphere and presence of a top coating. The resistors fired in the air after coating with overglaze, exhibited significantly lower sheet resistance, reduced impact of humidity and improved power capabilities.

Originality/value

In this paper, graphite-based resistors for applications in typical high-temperature cermet thick-film circuits were presented, whereas typical graphite-based resistors were fabricated in polymer thick-film technology. Owing to very low cost of the graphite, the material is suitable for low-power passive circuits, where components are not subjected into high temperature, above the typical temperature of operation of standard electronic components.

Details

Circuit World, vol. 47 no. 2
Type: Research Article
ISSN: 0305-6120

Keywords

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Article
Publication date: 1 March 1994

P McGeehin, P T Moseley and D E Williams

Describes research into methods for treating solid state gas sensors tocreate a multisensor system with both multi‐gas analysis andself‐diagnostic capabilities. Outlines…

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167

Abstract

Describes research into methods for treating solid state gas sensors to create a multisensor system with both multi‐gas analysis and self‐diagnostic capabilities. Outlines the three main categories of solid state gas sensors and then discusses the need for a systematic approach to semiconductor sensor design and the phenomenology of new sensor materials. Concludes that theoretically a self‐diagnostic sensor array device can be conceived for utilisation in gas sensing.

Details

Sensor Review, vol. 14 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 17 June 2021

Mohammed Gamil, Nagih M. Shaalan and Ahmed Abd El-Moneim

This study aims to present an efficient and reliable graphene nanoplatelets (GNPs)-based temperature sensor.

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98

Abstract

Purpose

This study aims to present an efficient and reliable graphene nanoplatelets (GNPs)-based temperature sensor.

Design/methodology/approach

A high-quality dispersion of GNPs was dropped by casting method on platinum electrodes deposited on a polyethylene terephthalate (PET) substrate. The GNPs were characterized by scanning electron microscope, Raman spectroscopy and X-ray diffraction spectra to ensure its purity and quality. The temperature sensing behavior of the fabricated sensor was examined by subjecting it to different temperatures, range from room temperature (RT) to 150 °C.

Findings

Excellent resistance linearity with temperature change was achieved. Temperature coefficient of resistance of the fabricated sensor was calculated as 1.4 × 10–3°C. The sensor also showed excellent repeatability and stability for the measured temperature range. Good response and recovery times were evaluated at all the measured temperatures. With measuring the sensor response, the ambient temperature can be determined.

Originality/value

The present work presents a new simply and low cost fabricated temperature sensor based on GNPs working at a wide temperature range.

Details

Sensor Review, vol. 41 no. 3
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 1 April 2001

J.K. Atkinson, R.P. Sion and Z. Zhang

An experimental study of thick film strain sensitive resistors as typically employed in resistive bridge interface circuits has been undertaken. It has been found that the…

Abstract

An experimental study of thick film strain sensitive resistors as typically employed in resistive bridge interface circuits has been undertaken. It has been found that the chosen aspect ratio (length to width ratio) of these screen printed and fired thick film resistors has a significant effect on both the temperature coefficient of resistance and the low frequency noise characteristics of the devices. This sensitivity to aspect ratio has been attributed to metal end contact migration in the devices during firing and hence a relationship between the sensitivity and the choice of end contact material and the firing regime employed in device fabrication has also been identified.

Details

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

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Article
Publication date: 8 May 2009

Z. Pruszowski, P. Kowalik, M. Cież and J. Kulawik

The purpose of this paper is to characterize electrical parameters of amorphous Ni‐P resistive layers used for fabrication of precise resistors.

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196

Abstract

Purpose

The purpose of this paper is to characterize electrical parameters of amorphous Ni‐P resistive layers used for fabrication of precise resistors.

Design/methodology/approach

Ni‐P resistive layers were produced by the chemical process in water solution using Ni2 +  and H2PO2 ions. The paper presents the results of the studies concerning the influence of bath acidity and conditions of thermal stabilization on the structure and temperature coefficient of resistance of Ni‐P alloy.

Findings

The temperature coefficient of resistance of amorphous Ni‐P layers was found to depend significantly on the parameters of chemical metallisation process. It was stated that the changes of through‐casing resistivity versus the acidity of technological solution have roughly parabolic characteristics.

Originality/value

In this paper, it was at first explained how the changes of the structure of Ni‐P resistive layers depend on their temperature coefficient of capacitance.

Details

Microelectronics International, vol. 26 no. 2
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 25 July 2008

Y. Srinivasa Rao

The purpose of this paper is to study the variation of the temperature coefficient of resistance (TCR) of polymer thick film resistors, namely, PVC‐graphite thick film…

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413

Abstract

Purpose

The purpose of this paper is to study the variation of the temperature coefficient of resistance (TCR) of polymer thick film resistors, namely, PVC‐graphite thick film resistors, with parameters such as volume fraction, grain size, and high voltage.

Design/methodology/approach

A model is proposed to explain the observed variations, which assumes that the texture of the thick film resistors consists of insulator granules coated with conducting particles.

Findings

The paper finds that the TCR of these materials is controlled mainly by the contact resistance fluctuations between the conducting particles and the number of contacts each particle has with it neighbours. The variation of TCR with high voltage has also been explained with the help of this model and it is attributed to the changes in contact area and the number of contacts.

Originality/value

The value of the paper is in showing that apparently the TCR of polymer thick film resistors can be controlled by the expansion properties of the insulating medium. The variation of TCR with high voltage is also due to change in number of contacts between the conducting particles. These types of material may find applications in thermal sensors or as temperature control elements.

Details

Microelectronics International, vol. 25 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

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