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Article
Publication date: 1 April 2020

Mirosław Gracjan Gierczak, Eugeniusz Prociów and Andrzej Dziedzic

This paper aims to focus on the fabrication and characterization of mixed thin-/thick-film thermoelectric microgenerators, based on magnetron sputtered constantan…

Abstract

Purpose

This paper aims to focus on the fabrication and characterization of mixed thin-/thick-film thermoelectric microgenerators, based on magnetron sputtered constantan (copper–nickel alloy) and screen-printed silver. To improve the adhesion of the constantan layer to the applied substrates, the additional chromium sublayer was used. The aim of the study was to investigate the influence of chromium sublayer on the electrical and thermoelectric properties of such hybrid microgenerators.

Design/methodology/approach

Fabrication of such structures consisted of several steps – magnetron sputtering of the chromium and then constantan layer, exposing the first arms of thermocouples, applying the second arms by screen-printing technology and firing the prepared structures in a belt furnace. The structures were made both on Al2O3 (alumina) and low temperature co-fired ceramics (LTCC) substrates.

Findings

To the best of the authors’ knowledge, for the first time, laser ablation process was applied to fabricate the first arms of thermocouples from a layer of constantan only or constantan with a chromium sublayer. Geometric measurements have shown that the mapping of mask pattern by laser ablation technique is very accurate.

Originality/value

The determined Seebeck coefficient of the realized structures was about 40.4 µV/K. After firing the exemplary structures at 850°C peak temperature, Seebeck coefficient is increased to an average value of 51 µV/K.

Details

Microelectronics International, vol. 37 no. 2
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 7 August 2017

Miroslaw Gracjan Gierczak, Jacek Wróblewski and Andrzej Dziedzic

The paper focuses on design, fabrication and characterization of electromagnetic microgenerators with integrated rectifying circuits to convert AC output signal to DC one…

Abstract

Purpose

The paper focuses on design, fabrication and characterization of electromagnetic microgenerators with integrated rectifying circuits to convert AC output signal to DC one. The work includes research on simulation of voltage-rectifying circuits, including charge pump, realization of the experimental printed circuit board (PCB) with selected electronic circuits and the execution of the final structure with integrated rectifying circuit. Measurements were performed on these circuits.

Design/methodology/approach

Electromagnetic microgenerators include multipole permanent magnets secured on rotor three-phase brushless direct current (BLDC) motor and planar multilayer multiple coils. These were fabricated using low temperature co-fired ceramics (LTCC) technology. In our experiment, six rectifying circuits were simulated and tested with a structure consisting of eight layers of coils and with an outer diameter of 50 mm fabricated earlier.

Findings

The microgenerator with Graetz bridge generates higher output power than the modified charge pump at the same rotary speed. However, it is less stable for the distance change between the structure and the magnets than the modified charge pump, which has more constant output power in a wider range of load resistance.

Originality/value

The presented electronic rectifying circuits are novel for LTCC-based electromagnetic microgenerator application. The structure with integrated rectifying circuits allows generation of electrical output power larger than 100 mW at the rotor speed of about 8,000 rpm.

Details

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

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Article
Publication date: 1 August 2016

Piotr M. Markowski

The purpose of this paper was to develop the methodology of thick-film/low temperature co-fired ceramic (LTCC) multilayer thermoelectric microgenerator fabrication…

Abstract

Purpose

The purpose of this paper was to develop the methodology of thick-film/low temperature co-fired ceramic (LTCC) multilayer thermoelectric microgenerator fabrication including the procedure of silver-nickel thermocouples integration with LTCC.

Design/methodology/approach

To miniaturize the structures and to increase the output parameters (generated voltage, electrical power), the microgenerator was designed as multilayer systems. It allows to reduce size of the system and to increase the number of thermocouples integrated inside the structure. It also protects buried thermocouples against exposure to harmful external factors (e.g. moisture, oxidation and mechanical exposures). As a substrate, LTCC was used. For the thermocouples fabrication, thick-film pastes based on silver and nickel were chosen. Ag/Ni thermocouple has nearly three times higher Seebeck coefficient and 30 per cent lower electrical resistance than the combination of Ag/PdAg used in previous works of the author.

Findings

A multi-layer thick-film thermoelectric generator based on LTCC and Ag, Ni pastes was fabricated. Thirty Ag/Ni thermocouples were precisely screen-printed on few layers. Thermocouples’ arms are 15 mm long and about 150 μm wide. Interlayer connections (via-holes filled with conductive paste) provided the electrical contact between the layers. The biggest fabricated harvester consisted of 90 miniature thermocouples buried inside the LTCC.

Originality/value

The paper presents the results of research that provided to optimize the co-firing process of the LTCC/Ni set. In the result, the methodology of co-firing of silver-nickel thermocouples and LTCC ceramic was elaborated. Also, the methodology of fabrication of miniature thermoelectric energy harvesters was optimized.

Details

Microelectronics International, vol. 33 no. 3
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 2 August 2011

Piotr Markowski

The purpose of this paper is to investigate the possible application of thick‐film, metal‐based thermocouples to microsystems power supply. The subject of matter was…

Abstract

Purpose

The purpose of this paper is to investigate the possible application of thick‐film, metal‐based thermocouples to microsystems power supply. The subject of matter was development of the procedure of thick‐film thermopile miniaturisation.

Design/methodology/approach

The aptitude of four photoimageable inks (based on silver or silver‐palladium) to fabrication of miniaturised thermocouples' arms was investigated. The object of interest was their compatibility with different kinds of low temperature cofired ceramic (LTCC) substrates, maximum resolution, shrinkage and electrical resistivity. Usage of the laser shaping technique to fabrication of narrow thermocouples' arms was also subject of matter. After tests and processes optimization both techniques were combined to fabricate the thick‐film Ag/Ni microthermopile.

Findings

Most of investigated inks were compatible with all tested LTCC tapes – fired as well as unfired (green tapes). Photoimageable inks technique can be successfully used for thermocouples' arms miniaturization. 40 μm/40 μm line/spaces resolution can be easily achieved. Combining this technique with laser shaping enabled microthermopile fabrication. It consisted of 42 Ag (photoimageable)/Ni (laser shaped) thermocouples. Arms width was 40 μm and 225 μm (Ag‐ and Ni‐arm, respectively), spaces between them – 65 μm. Overall, width of single thermocouple was smaller than 0.4 mm.

Practical implications

Fabrication of microthermopile consisting of several hundreds of thick‐film thermocouples will be possible if described procedure is applied. Such microgenerator will generate output power sufficient to supply some microsystems or microelectronic circuits.

Originality/value

The properties of four photoimageable inks were investigated as well as their compatibility with five different LTCC substrates (fired and unfired). Procedure of thick‐film microthermopile fabrication using photoimageable inks technique combined with laser shaping was proposed for the first time.

Details

Microelectronics International, vol. 28 no. 3
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 14 September 2010

Robert Bogue

The paper aims to provide a technical review of new and emerging power sources and their application to sensors.

Abstract

Purpose

The paper aims to provide a technical review of new and emerging power sources and their application to sensors.

Design/methodology/approach

This is the second part of a two‐part paper. Following a brief introduction, recent developments and research into fuel cell, energy harvesting, microgenerator and wireless power transmission technologies are considered.

Findings

All of these technologies are the topic of a major research effort and offer prospects to power future generations of sensors. Several pose strong competition to rechargeable batteties.

Originality/value

The paper provides a detailed insight into new and improved sensor power sources.

Details

Sensor Review, vol. 30 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 26 June 2009

Robert Bogue

The purpose of this paper is to review the development of energy harvesting techniques and their use with wireless, self‐powered sensors.

Abstract

Purpose

The purpose of this paper is to review the development of energy harvesting techniques and their use with wireless, self‐powered sensors.

Design/methodology/approach

This paper first considers the need for wireless sensors and then discusses a number of products and recent development activities.

Findings

Energy harvesting devices based on electrodynamic, piezoelectric and thermoelectric effects, implemented through electromechanical, microelectromechanical systems and nanotechnological approaches, are attracting strong academic and commercial interest. A limited number of sensors and systems exploiting these effects are in production and many more are under development. Some actual and anticipated applications include industrial condition monitoring, structural monitoring and healthcare.

Originality/value

This provides a technical insight into energy harvesting techniques and their applications to wireless sensing.

Details

Sensor Review, vol. 29 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 30 January 2007

Abstract

Details

Sensor Review, vol. 27 no. 1
Type: Research Article
ISSN: 0260-2288

Content available
Article
Publication date: 18 September 2007

Abstract

Details

Sensor Review, vol. 27 no. 4
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 3 August 2015

Piotr Markowski, Eugeniusz Prociów and Łukasz Urbaniak

The purpose of this paper is to determine the thermoelectric properties of the germanium-based thin films and selecting the most suitable ones for fabrication of…

Abstract

Purpose

The purpose of this paper is to determine the thermoelectric properties of the germanium-based thin films and selecting the most suitable ones for fabrication of micrognerators.

Design/methodology/approach

The germanium layers were deposited by low pressure magnetron sputtering method, in the pressure of 10−3/104 mbar range. The amount of dopants (germanium or vanadium) was changed in a limited extent. The influence of such changes on the layers output properties was studied. Post-processing heat treatment at temperature below 823 K was applied to activate the layers. It leads to improve the electrical and thermoelectrical performance.

Findings

The special attention was paid to the power factor (PF = S2/ρ) of the layers. To estimate power factor (PF) electrical resistivity (ρ) and Seebeck coefficient (S) were determined. The achieved Seebeck coefficient value was 185 Volt/Kelvin (μV/K) for germanium doped with vanadium (Ge:V1.15) and 225 μV/K for germanium doped with gold(Ge:Au3.13) layers at room temperature. After activation process, the PF reached a value of 2.5 × 10−4 W/m · K2 for the Ge:Au3.13 and 1.1 × 10−4 W/m · K2 for the Ge:V1.15 layers.

Originality/value

The fabricated thermoelectric layers can be thermally annealed in temperature up to 823 K in the air and in 1,023 K under a nitrogen atmosphere. This enables integration of thin layers with thick-film technology. Corning glass or low temperature cofired ceramic was used as a substrate.

Details

Microelectronics International, vol. 32 no. 3
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 14 September 2010

Robert Bogue

The purpose of this paper is to review recent developments in wireless‐sensing technologies, products and applications.

Abstract

Purpose

The purpose of this paper is to review recent developments in wireless‐sensing technologies, products and applications.

Design/methodology/approach

The paper describes wireless sensor technologies, discusses the research efforts aimed at yielding battery‐free devices and considers a range of products, developments and applications.

Findings

The paper shows that emerging families of wireless sensors are being used in a wide range of applications in many industries. These include process control, condition and structural monitoring, energy management, automotive safety, healthcare and security. Major efforts are underway to develop battery‐free devices based on energy‐harvesting and other techniques.

Originality/value

The paper provides a technical review of the rapidly developing field of wireless‐sensing technology.

Details

Sensor Review, vol. 30 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

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