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Article
Publication date: 1 April 1987

D.A. PARKER and G.M. DONNISON

The concept of an air‐gap insulated piston has been explored using bolted and welded/roll bonded designs. Pistons with bolted‐on crowns demonstrated the effectiveness of…

Abstract

The concept of an air‐gap insulated piston has been explored using bolted and welded/roll bonded designs. Pistons with bolted‐on crowns demonstrated the effectiveness of air gap insulation, but roll bonded and welded designs were found to be more robust and to provide the complete sealing of the air gap necessary for continued insulation. Evolution of the design to combine high insulation with adequate durability is discussed. Engine running times of up to 200 hours at full load have been achieved for an air gap piston which reduces heat flow to the crown by 33 per cent. An improved design giving 41 per cent reduction of heat flow has been tested for 78 hours at full engine load with no evident deterioration. Development is continuing to provide a fully durable piston achieving up to 50 per cent reduction in heat flow.

Details

Industrial Lubrication and Tribology, vol. 39 no. 4
Type: Research Article
ISSN: 0036-8792

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Book part
Publication date: 17 September 2014

Jamshid Beheshti, Mohammed J. AlGhamdi, Charles Cole, Dhary Abuhimed and Isabelle Lamoureux

The chapter describes a four-year research project, the objective of which was to design and develop an intervention tool to assist middle school students in their…

Abstract

Purpose

The chapter describes a four-year research project, the objective of which was to design and develop an intervention tool to assist middle school students in their information seeking when engaged in an inquiry-based learning project.

Methodology/approach

Bonded design method was used to design a proof-of-concept (POC) low-tech Guide, and focus group and Informant Design methods were utilized to develop a Web Guide.

Findings

In creating an intervention tool, whether low-tech paper-based or high-tech websites, different methodologies that relied heavily on the participation of students in the design process were successfully utilized.

Practical implications

The research shows that participation of children and adolescents in designing the content of technology for educational use is imperative.

Originality/value

This is a long-term research project, which is unparalleled and unique in its scope, duration, breadth, and depth. Having access to the grade eight classes in a single school over a four-year period has proven to be a remarkable research opportunity, seldom reported in the literature.

Details

New Directions in Children’s and Adolescents’ Information Behavior Research
Type: Book
ISBN: 978-1-78350-814-3

Keywords

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Article
Publication date: 1 January 1990

J.H. Lau, S.J. Erasmus and D.W. Rice

A review of state‐of‐the‐art technology pertinent to tape automated bonding (for fine pitch, high I/O, high performance, high yield, high volume and high reliability) is…

Abstract

A review of state‐of‐the‐art technology pertinent to tape automated bonding (for fine pitch, high I/O, high performance, high yield, high volume and high reliability) is presented. Emphasis is placed on a new understanding of the key elements (for example, tapes, bumps, inner lead bonding, testing and burn‐in on tape‐with‐chip, encapsulation, outer lead bonding, thermal management, reliability and rework) of this rapidly moving technology.

Details

Circuit World, vol. 16 no. 2
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 20 July 2021

Valerie Nesset, Elisabeth C. Davis, Owen Stewart-Robertson and J. Brice Bible

This paper examines how bonded design (BD), a participatory design methodology, was influenced by the transition to working in a virtual environment necessitated by the…

Abstract

Purpose

This paper examines how bonded design (BD), a participatory design methodology, was influenced by the transition to working in a virtual environment necessitated by the coronavirus disease 2019 (COVID-19) pandemic.

Design/methodology/approach

Abiding by the participatory design tenets of creativity, learning-by-doing and mutual learning, the BD methodology was created for the specific purpose of fostering meaningful communication and interaction between two disparate groups. Previous iterations of BD are discussed, including its naissance with intergenerational teams, its adaptation to provide a framework for a university-wide initiative, the Faculty Information Technology (IT) Liaison Program that brought together faculty members and IT professional staff, and its current use in helping public librarians to develop with older adults, targeted library programming and services.

Findings

Analysis of the findings from the assessment of the BD methodology in different physical contexts demonstrates that the flexibility in the makeup and order of design techniques (discussion, evaluation, brainstorming, prototyping, consensus-building) makes BD potentially adaptable to online spaces. Recommendations for implementing the BD methodology online are outlined. It is argued that BD’s adaptability makes it an ideal method for creating meaningful and productive collaborations within both physical and virtual environments.

Originality/value

The proposed iteration of the BD methodology responds to a need for innovative practices to foster collaborative work in a virtual environment. BD is a unique, inclusive and cost-effective methodology to encourage meaningful interaction and communication between disparate groups in physical or online contexts.

Details

Journal of Documentation, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0022-0418

Keywords

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Article
Publication date: 1 November 1967

D. Ris

ESTABLISHING A STANDARD SOME twenty‐two years ago Dr de Bruyne invented the Redux system for joining metal to metal in a manner suitable for use in aircraft construction…

Abstract

ESTABLISHING A STANDARD SOME twenty‐two years ago Dr de Bruyne invented the Redux system for joining metal to metal in a manner suitable for use in aircraft construction The phenol‐formaldehyde/polyvinyl‐formal formulation of this system is still widely used today. What is it that has made this system such a success through the years?

Details

Aircraft Engineering and Aerospace Technology, vol. 39 no. 11
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 18 April 2008

W.D. van Driel, R.B.R. van Silfhout and G.Q. Zhang

At present, over 95 percent of the manufactured packages are still being wire bonded. Owing to the ongoing trend of miniaturization, material changes, and cost reduction…

Abstract

Purpose

At present, over 95 percent of the manufactured packages are still being wire bonded. Owing to the ongoing trend of miniaturization, material changes, and cost reduction, wire bond‐related failures are becoming increasingly important. This paper aims to understand these kinds of failures.

Design/methodology/approach

Different finite element (FE) techniques are explored to their ability to describe the thermo‐mechanical behavior of the wire embedded in the electronic package. The developed nonlinear and parametric FE models are able to predict the strong nonlinear behavior of wire failures and multi‐failure mode interaction accurately and efficiently.

Findings

It is found that both processing and testing environments as well as the occurrence of delamination strongly increase the risk for wire failures. The results indicate that processing and testing influences are much less than those of the delamination.

Practical implications

Package designers should focus on limiting the occurrence of delamination around wire bond and/or stitch areas.

Originality/value

Combining the strengths of predictive modeling with simulation‐based optimization methods, the optimal wire shape is obtained.

Details

Microelectronics International, vol. 25 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

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Article
Publication date: 26 July 2013

Fei Zong, Zhi‐jie Wang, Yan‐bo Xu, Ji‐yong Niu and Han‐min Zhang

The purpose of this paper was to attempt to confirm the root cause of unstable stitch pull strength in PQFN package and propose some permanent solutions for it.

Abstract

Purpose

The purpose of this paper was to attempt to confirm the root cause of unstable stitch pull strength in PQFN package and propose some permanent solutions for it.

Design/methodology/approach

A screen experiment was designed to find the key process out of the manufacturing flow; a non‐destructive detaching method and cross section polishing were used to inspect the bond integrity; Auger analysis assisted with argon ion sputter was tried to confirm the contamination; finally the manufacturing processes were redesigned to prevent the contamination.

Findings

Some first aids of process optimization got little improvement; the screen experiment of processes found solder die bonding was the one resulted into a poor bond integrity which was demonstrated by non‐destructive detaching method and cross section inspection; Auger analysis assisted with argon ion sputter detected that there was a tin layer thicker than 20 nm coated on the bonding surface and the wire bondability of gold wire on this tin coating was poor; the lead frame was redesigned to prevent the wetting and flowing of tin and got a perfect performance.

Research limitations/implications

Because of the limitation of time and resources, the proposed solutions for this issue could be studied more deeply.

Originality/value

This paper set up an example how to find out the root cause from the complex manufacturing process flow and put forward a quick solution accordingly for the issue.

Details

Microelectronics International, vol. 30 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

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Article
Publication date: 1 August 1996

S. Greathouse

Known good die, flip chip and chip scale packages are technologies that offer variousadvantages to the board manufacturer. A discussion of the different types of package…

Abstract

Known good die, flip chip and chip scale packages are technologies that offer various advantages to the board manufacturer. A discussion of the different types of package options, their methods of assembly, test and performance comparisons can help to resolve the general direction a manufacturer might pursue for next generation systems. This paper attempts to give a perspective as well as highlighting the areas of concern with the different options.

Details

Microelectronics International, vol. 13 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

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Article
Publication date: 21 September 2010

De‐Shin Liu, Shu‐Shen Yeh, Chun‐Teh Kao, Pay‐Yau Huang, Chia‐I Tsai, An‐Hong Liu and Shu‐Ching Ho

The reliability of chip‐on‐film (COF) packages is fundamentally dependent upon the quality of the eutectic Au‐Sn joint formed between the Au bumps on the integrated…

Abstract

Purpose

The reliability of chip‐on‐film (COF) packages is fundamentally dependent upon the quality of the eutectic Au‐Sn joint formed between the Au bumps on the integrated circuit (IC) device and the Sn‐plated Cu inner leads. Therefore, it is essential that an appropriate bonding temperature is achieved during the inner lead bonding (ILB) process. The purpose of this paper is to identify the optimal processing conditions which maximize the reliability of the Au‐Sn joints.

Design/methodology/approach

The paper commences by performing an experimental investigation to establish the temperature at three specific locations within the COF/ILB system in a typical gang‐bonding process. The relationship between the setting temperature of the bonding tool and the temperature of the tool surface is then calibrated using an off‐line experimental system. An ANSYS finite element (FE) model is then constructed to simulate the temperature distribution within the COF/ILB system under representative temperature conditions. The validity of the numerical model is confirmed by comparing the simulation results with the experimental temperature measurements. The FE model is then used in a 23 factorial design process to evaluate the effect of the principal COF/ILB processing parameters, namely the contact area, the tool temperature and the stage temperature, on the temperature induced at the interface between the Au bumps on the IC chip and the Sn‐coated Cu leads on the polyimide film.

Findings

The results reveal that the interfacial bonding temperature is determined primarily by the stage temperature.

Originality/value

A regression analysis model is applied to the factorial design results to construct a COF/ILB design chart which enables the rapid identification of the stage and tool temperatures required to achieve the minimum feasible eutectic bonding temperature.

Details

Soldering & Surface Mount Technology, vol. 22 no. 4
Type: Research Article
ISSN: 0954-0911

Keywords

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Article
Publication date: 1 April 1989

T.C. Chung and H.A. Moore

Tape automated bonding (TAB) is one technology which is becoming widely adopted for interconnecting integrated circuits to a substrate or package. Both destructive and…

Abstract

Tape automated bonding (TAB) is one technology which is becoming widely adopted for interconnecting integrated circuits to a substrate or package. Both destructive and non‐destructive test methods for evaluation of TAB bonds are analysed and criticised. The key parameters and general guidelines of a destructive beampull test set‐up are identified and presented. The key features of four different non‐destructive test methods are described and discussed. It is found that no universal solution exists for non‐destructive evaluation of TAB bonds although some methods may be more useful than others under certain conditions and constraints. Data and experimental procedure are presented for correlation of scanning laser acoustic microscopy and beampull data.

Details

Circuit World, vol. 16 no. 1
Type: Research Article
ISSN: 0305-6120

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