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Article
Publication date: 15 May 2009

J.H.‐G. Ng, M.P.Y. Desmulliez, M. Lamponi, B.G. Moffat, A. McCarthy, H. Suyal, A.C. Walker, K.A. Prior and D.P. Hand

The purpose of this paper is to present a novel manufacturing process that aims to pattern metal tracks onto polyimide at atmospheric pressure and ambient environment. The process…

Abstract

Purpose

The purpose of this paper is to present a novel manufacturing process that aims to pattern metal tracks onto polyimide at atmospheric pressure and ambient environment. The process can be scaled up for industrial applications.

Design/methodology/approach

From a thorough literature survey, different approaches were carried out for processing polyimide. Following a design of experiments for the processing and various characterisation techniques, a micro‐coil was manufactured as a test demonstrator.

Findings

The characteristics of some main formaldehyde‐based electroless copper baths were compared. The quality of the sidewalls was characterised and the performance of the process was assessed.

Originality/value

This paper demonstrates a high‐value manufacturing technique that is mass manufacturable, low cost and suitable for use on 3D surfaces. Criteria required for the development of a direct‐writing process have been described. The issues surrounding electroless plating on polyimide have been explained.

Details

Circuit World, vol. 35 no. 2
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 18 May 2010

Rabindra N. Das, Frank D. Egitto and Voya R. Markovich

Material formulation, structuring and modification are key to increasing the unit volume complexity and density of next generation electronic packaging products. Laser processing…

Abstract

Purpose

Material formulation, structuring and modification are key to increasing the unit volume complexity and density of next generation electronic packaging products. Laser processing is finding an increasing number of applications in the fabrication of these advanced microelectronic devices. The purpose of this paper is to discuss the development of new laser‐processing capabilities involving the synthesis and optimization of materials for tunable device applications.

Design/methodology/approach

The paper focuses on the application of laser processing to two specific material areas, namely thin films and nanocomposite films. The examples include BaTiO3‐based thin films and BaTiO3 polymer‐based nanocomposites.

Findings

A variety of new regular and random 3D surface patterns are highlighted. A frequency‐tripled Nd:YAG laser operating at a wavelength of 355 nm is used for the micromachining study. The micromachining is used to make various patterned surface morphologies. Depending on the laser fluence used, one can form a “wavy,” random 3D structure, or an array of regular 3D patterns. Furthermore, the laser was used to generate free‐standing nano and micro particles from thin film surfaces. In the case of BaTiO3 polymer‐based nanocomposites, micromachining is used to generate arrays of variable‐thickness capacitors. The resultant thickness of the capacitors depends on the number of laser pulses applied. Micromachining is also used to make long, deep, multiple channels in capacitance layers. When these channels are filled with metal, the spacings between two metallized channels acted as individual vertical capacitors, and parallel connection eventually produce vertical multilayer capacitors. For a given volume of capacitor material, theoretical capacitance calculations are made for variable channel widths and spacings. For comparison, calculations are also made for a “normal” capacitor, that is, a horizontal capacitor having a single pair of electrodes.

Research limitations/implications

This technique can be used to prepare capacitors of various thicknesses from the same capacitance layer, and ultimately can produce variable capacitance density, or a library of capacitors. The process is also capable of making vertical 3D multilayer embedded capacitors from a single capacitance layer. The capacitance benefit of the vertical multilayer capacitors is more pronounced for thicker capacitance layers. The application of a laser processing approach can greatly enhance the utility and optimization of new materials and the devices formed from them.

Originality/value

Laser micromaching technology is developed to fabricate several new structures. It is possible to synthesize nano and micro particles from thin film surfaces. Laser micromachining can produce a variety of random, as well as regular, 3D patterns. As the demand grows for complex multifunctional embedded components for advanced organic packaging, laser micromachining will continue to provide unique opportunities.

Details

Circuit World, vol. 36 no. 2
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 24 January 2024

Yunfei Xing, Justin Zuopeng Zhang, Veda C. Storey and Alex Koohang

The global prevalence of social media and its potential to cause polarization are highly debated and impactful. The previous literature often assumes that the ideological bias of…

Abstract

Purpose

The global prevalence of social media and its potential to cause polarization are highly debated and impactful. The previous literature often assumes that the ideological bias of any media outlet remains static and exogenous to the polarization process. By studying polarization as a whole from an ecosystem approach, the authors aim to identify policies and strategies that can help mitigate the adverse effects of polarization and promote healthier online discourse.

Design/methodology/approach

To investigate online polarization, the authors perform a systematic review and analysis of approximately 400 research articles to explore the connection between cognitive bias and polarization, examining both causal and correlational evidence. The authors extensively evaluate and integrate existing research related to the correlation between online polarization and crucial factors such as public engagement, selective exposure and political democracy. From doing so, the authors then develop a PolarSphere ecosystem that captures and illustrates the process of online polarization formation.

Findings

The authors' review uncovers a wide range of associations, including ideological cognition, bias, public participation, misinformation and miscommunication, political democracy, echo chambers and selective exposure, heterogeneity and trust. Although the impact of bias on social media polarization depends on specific environments and internal/external conditions, certain variables exhibit strong associations across multiple contexts. The authors use these observations as a basis from which to construct PolarSphere, an ecosystem of bias-based polarization on social media, to theorize the process of polarization formation.

Originality/value

Based on the PolarSphere ecosystem, the authors argue that it is crucial for governments and civil societies to maintain vigilance and invest in further research to gain a deep comprehension of how cognitive bias affects online polarization, which could lead to ways to eliminate polarization.

Details

Journal of Enterprise Information Management, vol. 37 no. 1
Type: Research Article
ISSN: 1741-0398

Keywords

Article
Publication date: 4 January 2013

A.E.‐S.I. Ahmed, A.M. El‐Masry, A. Saleh and A. Nada

The purpose of this paper is to prepare and optimize the preparation conditions of some new hydrogels and in addition, evaluate their water absorbance at different mediums and…

Abstract

Purpose

The purpose of this paper is to prepare and optimize the preparation conditions of some new hydrogels and in addition, evaluate their water absorbance at different mediums and their ability to remove ions from aqueous solutions.

Design/methodology/approach

Cellulose was extracted from depithed bagasse at two different pulping conditions; 3 and 6 hours cooking times, pulp (I) and (II), respectively. These pulps, in addition to cotton linter for comparison, were grafted with acrylamide followed by cross‐linking with glutaraldehyde. The networks were partially hydrolyzed and the structures of products (before and after hydrolysis) were studied using FTIR, SEM, TGA and X‐ray. The optimum preparation conditions were identified, before and after hydrolysis, to achieve maximum absorbance and the ability of prepared hydrogels to remove ions from solutions was investigated.

Findings

Maximum level of absorption was recorded using hydrogels prepared with monomer concentration =0.8 mol/l, cross‐linker concentration =0.01 mol/l, reaction time =2 hours and temperature =65°C. Hydrogels prepared using pulp (I) showed the best absorbance behavior and a tendency to remove ions from water.

Research limitations/implications

The ability of the prepared gels to remove ions from water could be further investigated to evaluate the ability of their use in a multi‐filtration system for water treatment.

Practical implications

This piece of work has suggested a simple way to convert an agricultural waste to hydrogel able to remove metal ions from water.

Social implications

Consuming this type of waste reduces the risks resulting from its burning in some countries, such as Egypt, that produce large amounts of it.

Originality/value

In this paper, low cost hydrogels, with expected value in water treatment, were prepared using agricultural wastes. They have shown better reactivity than gels prepared using pure cellulosic materials (cotton linter).

Details

Pigment & Resin Technology, vol. 42 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

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