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1 – 10 of over 2000
Article
Publication date: 1 August 1999

Jaroslav Mackerle

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper…

2618

Abstract

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Details

Engineering Computations, vol. 16 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 3 May 2016

Sangbeom Cho, Venky Sundaram, Rao Tummala and Yogendra Joshi

The functionality of personal mobile electronics continues to increase, in turn driving the demand for higher logic-to-memory bandwidth. However, the number of inputs/outputs…

286

Abstract

Purpose

The functionality of personal mobile electronics continues to increase, in turn driving the demand for higher logic-to-memory bandwidth. However, the number of inputs/outputs supported by the current packaging technology is limited by the smallest achievable electrical line spacing, and the associated noise performance. Also, a growing trend in mobile systems is for the memory chips to be stacked to address the growing demand for memory bandwidth, which in turn gives rise to heat removal challenges. The glass interposer substrate is a promising packaging technology to address these emerging demands, because of its many advantages over the traditional organic substrate technology. However, glass has a fundamental limitation, namely low thermal conductivity (∼1 W/m K). The purpose of this paper is to quantify the thermal performance of glass interposer-based electronic packages by solving a multi-scale heat transfer problem for an interposer structure. Also, this paper studies the possible improvement in thermal performance by integrating a fluidic heat spreader or vapor chamber within the interposer.

Design/methodology/approach

This paper illustrates the multi-scale modeling approach applied for different components of the interposer, including Through Package Vias (TPVs) and copper traces. For geometrically intricate and repeating structures, such as interconnects and TPVs, the unit cell effective thermal conductivity approach was used. For non-repeating patterns, such as copper traces in redistribution layer, CAD drawing-based thermal resistance network analysis was used. At the end, the thermal performance of vapor chamber integrated within a glass interposer was estimated by using an enhanced effective thermal conductivity, calculated from the published thermal resistance data, in conjunction with the analytical expression for thermal resistance for a given geometry of the vapor chamber.

Findings

The limitations arising from the low thermal conductivity of glass can be addressed by using copper structures and vapor chamber technology.

Originality/value

A few reports can be found on thermal performance of glass interposers. However thermal characteristics of glass interposer with advanced cooling technology have not been reported.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 26 no. 3/4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 9 July 2020

Pavel Baranov, Tamara Nesterenko, Evgenii Barbin and Aleksei Koleda

One of the problems encountered by developers of inertial systems, such as gyroscopes and accelerometers, is the critical dependence of the eigenfrequencies of elastic suspensions…

93

Abstract

Purpose

One of the problems encountered by developers of inertial systems, such as gyroscopes and accelerometers, is the critical dependence of the eigenfrequencies of elastic suspensions (ES) on temperature when using substrates for sensors made of dielectric materials, such as borosilicate glass. The internal stresses arising in the ES caused by the difference in the temperature coefficients of linear expansion (TCLE) lead to deformation of the sensor and complication of the electronic part of the sensor. The purpose of this paper is to approach for in-plane and out-of-plane ES are considered that allow for minimization of the influence of internal stresses on eigenfrequencies.

Design/methodology/approach

Analytical, finite element and experimental results are considered. The temperature coefficient of thermal expansion, the Young’s modulus and the Poisson ratio are given as a function of temperature. The shape of the spring elements (SEs) and the construction of the elastic suspension are the main topics of focus in this study. The authors’ out-of-plane ES based on a meander-like spring element implemented via finite element modeling show good agreement with the experimental results.

Findings

Meander-like SEs have been developed that have lower temperature errors in comparison with traditional types of SEs. The main contribution to the change in the eigenfrequency from temperature is made by internal stresses that arose from the deformation of the bonded materials with different TCLE. The change of eigenfrequency from the temperatures that were calculated by finite element method did not exceed 0.15%, however, in practice, the scatter of the obtained characteristics for different samples showed a change of up to 0.3%.

Originality/value

This study shows a way to design and optimize the structure and theoretical background for the development of the microelectromechanical systems (MEMS) inertial module combining the functions of gyroscope and accelerometer. The obtained results will improve and expand the manufacturing technology of MEMS gyroscopes and accelerometers.

Article
Publication date: 1 April 2005

Jaroslav Mackerle

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or…

5146

Abstract

Purpose

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or as welding and brazing fixtures, etc. Ceramic materials are frequently used in industries where a wear and chemical resistance are required criteria (seals, liners, grinding wheels, machining tools, etc.). Electrical, magnetic and optical properties of ceramic materials are important in electrical and electronic industries where these materials are used as sensors and actuators, integrated circuits, piezoelectric transducers, ultrasonic devices, microwave devices, magnetic tapes, and in other applications. A significant amount of literature is available on the finite element modelling (FEM) of ceramics and glass. This paper gives a listing of these published papers and is a continuation of the author's bibliography entitled “Finite element modelling of ceramics and glass” and published in Engineering Computations, Vol. 16, 1999, pp. 510‐71 for the period 1977‐1998.

Design/methodology/approach

The form of the paper is a bibliography. Listed references have been retrieved from the author's database, MAKEBASE. Also Compendex has been checked. The period is 1998‐2004.

Findings

Provides a listing of 1,432 references. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Originality/value

This paper makes it easy for professionals working with the numerical methods with applications to ceramics and glasses to be up‐to‐date in an effective way.

Details

Engineering Computations, vol. 22 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 21 March 2016

Robert Bogue

This paper aims to provide details of miniaturised analytical instrument technologies and developments.

Abstract

Purpose

This paper aims to provide details of miniaturised analytical instrument technologies and developments.

Design/methodology/approach

Following an introduction and historical background, this first considers miniaturised chromatographs and spectrometers based on micro-electromechanical system (MEMS)/micro total analytical system technologies. It then discusses lab-on-a-chip developments with an emphasis on capillary electrophoresis. Developments in the emerging lab-on-paper technology are then considered and are followed by brief concluding comments.

Findings

This shows that many classes of analytical instruments which offer a number of operational and economic benefits have been miniaturised through the use of microfabrication and other technologies. They are an active field of research and are based on silicon, glass, polymers and even paper and are underpinned by developments in microfluidics and optofluidics and fabrication techniques which include lithography, MEMS and micro-opto-electromechanical system.

Originality/value

This provides an insight into the rapidly developing field of miniaturised analytical instrument technologies.

Details

Sensor Review, vol. 36 no. 2
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 26 June 2019

Pavel Baranov, Tamara Nesterenko, Evgenii Barbin, Aleksej Koleda, Shuji Tanaka, Takashiro Tsukamoto, Ivan Kulinich, Dmitry Zykov and Alexander Shelupanov

Technological capabilities of manufacturing microelectromechanical system (MEMS) gyroscopes are still insufficient if compared to manufacturing high-efficient gyroscopes and…

371

Abstract

Purpose

Technological capabilities of manufacturing microelectromechanical system (MEMS) gyroscopes are still insufficient if compared to manufacturing high-efficient gyroscopes and accelerometers. This creates weaknesses in their mechanical structure and restrictions in the measurement accuracy, stability and reliability of MEMS gyroscopes and accelerometers. This paper aims to develop a new architectural solutions for optimization of MEMS gyroscopes and accelerometers and propose a multi-axis MEMS inertial module combining the functions of gyroscope and accelerometer.

Design/methodology/approach

The finite element modeling (FEM) and the modal analysis in FEM are used for sensing, drive and control electrode capacitances of the multi-axis MEMS inertial module with the proposed new architecture. The description is given to its step-by-step process of manufacturing. Algorithms are developed to detect its angular rates and linear acceleration along three Cartesian axes.

Findings

Experimental results are obtained for eigenfrequencies and capacitances of sensing, drive and control electrodes for 50 manufactured prototypes of the silicon electromechanical sensor (SES). For 42 SES prototypes, a good match is observed between the calculated and simulated capacitance values of comb electrodes. Thus, the mean-square deviation is not over 20 per cent. The maximum difference between the calculated and simulated eigenfrequencies in the drive channel of 11 SES prototypes is not over 3 per cent. The same difference is detected for eigenfrequencies in the first sensing channel of 17 SES prototypes.

Originality/value

This study shows a way to design and optimize the structure and theoretical background for the development of the MEMS inertial module combining the functions of gyroscope and accelerometer. The obtained results will improve and expand the manufacturing technology of MEMS gyroscopes and accelerometers.

Details

Sensor Review, vol. 39 no. 5
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 1 October 1951

G.N. GADSBY

ALTHOUGH the element silicon is second only to oxygen in order of abundance in the earth's crust the chemistry of its compounds and in particular of organo‐silicon compounds had…

Abstract

ALTHOUGH the element silicon is second only to oxygen in order of abundance in the earth's crust the chemistry of its compounds and in particular of organo‐silicon compounds had developed but little before the turn of the century. It is true that the German chemist Friedel and his students Crafts and Ladenburg and later Polis prepared a few isolated organo‐silicon compounds during the latter half of the nineteenth century (1863–1886), but the land mark in this field is undoubtedly the classical work of Professor F. S. Kipping and his school at University College, Nottingham. This work extended over nearly forty years from 1899 to 1937 during which time a systematic study was made of this branch of chemistry.

Details

Industrial Lubrication and Tribology, vol. 3 no. 10
Type: Research Article
ISSN: 0036-8792

Article
Publication date: 13 February 2007

David A. Hutt, Karen Williams, Paul P. Conway, Fuad M. Khoshnaw, Xiaoyun Cui and Deepa Bhatt

To present the aims and preliminary findings of a research project to investigate the manufacture of multilayer glass substrates built up from thin glass sheets.

Abstract

Purpose

To present the aims and preliminary findings of a research project to investigate the manufacture of multilayer glass substrates built up from thin glass sheets.

Design/methodology/approach

The approaches that may be taken to create glass substrates and the challenges involved are described. Excimer laser machining was used for the formation of microvias and other features in individual glass sheets. In addition, methods for the electroless copper metallisation of the smooth glass surfaces were studied. Finally, a technique for the lamination of the glass layers using low temperature, pressure assisted bonding was investigated.

Findings

Microvias with 100 μm diameter entry holes were successfully machined in 100 μm thick glass sheets and process windows were identified to reduce debris and hole taper. Using appropriate pre‐treatment steps, electroless copper coatings could be deposited uniformly over the smooth glass surface, however, further improvements in adhesion were found to be necessary. The direct lamination of glass layers was found to be possible using pressure and temperature applied over long periods of time. Improvements to the lamination process were made to reduce the initiation of cracks which were assessed using fatigue testing.

Research limitations/implications

The feasibility of the individual steps in the fabrication of glass substrates has been demonstrated. Further work is necessary to control the processes in order to limit microcrack formation, improve copper coating adhesion and ensure uniform lamination of multiple glass layers.

Originality/value

The use of glass materials could enable the manufacture of substrates for high density electrical interconnect with integrated optical waveguides.

Details

Circuit World, vol. 33 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 20 September 2019

Farah Khaleda Mohd Zaini, Vengadaesvaran Balakrishnan, A. Syafiq, Nasrudin Abd. Rahim, A.K. Pandey, Ramesh Kasi and Ramesh Subramaniam

The purpose of this paper is to implement coating system by varying the amount of nano-sized titanium dioxide, (nano-TiO2) combined with various organic binders and to study the…

Abstract

Purpose

The purpose of this paper is to implement coating system by varying the amount of nano-sized titanium dioxide, (nano-TiO2) combined with various organic binders and to study the coating effects on the performance of solar cell in terms of temperature and efficiency.

Design/methodology/approach

Nano-TiO2 coatings are developed in two types of binder networks; the combination of methyltrimethoxy silane (MTMS) and nitric acid and the combination of 3-aminopropyl triethoxysilane (APTES) and MTMS. Overall, the formulations method was cost-effective, produces good transparency, clear and managed to dry at room temperature. The coating mixtures were applied onto the glass substrate by using the dip-coating method and the coated substrate were sent for several characterizations.

Findings

This study demonstrated that TiO2 nanoparticle coating in APTES/MTMS matrix showed a thermal-decreasing result on solar cells, where the cell temperature is reduced to 46.81°C (T2 coating type) from 55.74°C (without coating) after 1-h exposure under 1,000 W/m2 irradiance in a solar simulator. Contrary to prior works where solar cell coatings were reported to reduce the cell temperature at the expense of the cell efficiency, the results from this study reported an improved fill factor (FF) of solar cells. From the photovoltaic (PV) characteristics study, the FF for solar cells is increased by approximately 0.2, i.e. 33.3 per cent, for all coatings compared to the non-coated cell.

Research limitations/implications

Findings will be able to contribute in the development of temperature-reducing and efficiency-enhancing coating for PV panels.

Practical implications

A simple dip-coating method provides an even distribution of TiO2 nanoparticle coating on the glass panel, which is cost-effective and time-efficient to reduce the temperature of solar cell while maintaining its efficiency.

Originality/value

The ability of nano-TiO2 coatings with a simple fabrication method and the right solution to reduce the surface temperature of solar cells while improving the FF of the cells.

Details

Pigment & Resin Technology, vol. 49 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 15 April 2020

Bassam Abdallah, Mahmoud Kakhia and Walaa Zetoune

This study aims to carry out the deposition of zinc sulfide (ZnS) thick films on glass and silicon (100) substrates using radio frequency (RF) magnetron sputtering method at…

Abstract

Purpose

This study aims to carry out the deposition of zinc sulfide (ZnS) thick films on glass and silicon (100) substrates using radio frequency (RF) magnetron sputtering method at different powers. Film structure has been analyzed by X-ray diffraction (XRD); the patterns showed that the films possesses a cubic structure with (111) preferred orientation. Photoluminance (PL) intensity of the films has been related to the crystallinity, which is varied with the power.

Design/methodology/approach

Scanning electron microscope (SEM) images have been used to discover the films’ morphology. The stoichiometry has been confirmed by energy dispersive X-ray spectroscopy (EDX) analysis. MicroRaman spectroscopy has been used to validate the film structure. Gas-sensing studies were carried out by means of a static gas chamber to sense acetone, ethanol, methanol, H2O and NH3 vapor in air ambient.

Findings

ZnS has a stoichiometric and cubic structure. The band gaps and photoluminance intensity of the films are correlated with the crystallinity, which is varied with the power. The EDX analysis approved the stoichiometry of the prepared films. Acetone, ethanol, humidity (H2O), methanol and NH3 vapor gases were used to justify the sensing properties at 25°C of the thickest ZnS film.

Originality/value

High-quality ZnS films have been obtained at different powers without annealing. Gases sensing properties at 25°C are justified for deposited ZnS films using acetone, ethanol, humidity (H2O), methanol and NH3 vapor gases. It reveals good response for NH3 and humidity vapors at room temperature; the sensing functioning at this temperature was attractive in recent research.

Details

World Journal of Engineering, vol. 17 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

1 – 10 of over 2000