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Article
Publication date: 16 August 2019

Zhihua Tao, Guanting Liu, Yuanxun Li and Hua Su

The adsorption and acceleration behavior of 3-mercaptopropyl sulfonate (MPS) were investigated by electrochemical tests for microvia filling by copper electroplating.

Abstract

Purpose

The adsorption and acceleration behavior of 3-mercaptopropyl sulfonate (MPS) were investigated by electrochemical tests for microvia filling by copper electroplating.

Design/methodology/approach

The synergistic effects of one suppressor of propylene oxide ethylene oxide propylene oxide named PEP and MPS as the accelerator during copper electroplating were also investigated by electrochemical methods such as electrochemical impedance spectroscopy cyclic voltammetric stripping (CVS) and Galvanostatic measurements (GMs).

Findings

The research results suggest that the adsorption of MPS onto the Cu-RDE metal surface was a spontaneous process and the adsorbing of MPS on cathode was proposed to physical-chemistry adsorption in the plating formula. There was no potential difference (i.e. ?? = 0) of GMs until MPS was injected into the plating solution suggest that copper deposition is not diffusion-controlled in the presence of PEP–Cl–JGB.

Originality/value

A new composition of plating bath was found to be effective to perform bottom-up copper filling of microvias in the fabrication of PCB in electronic industries. The adsorption of MPS into the Cu-RDE metal surface was a spontaneous process and the adsorbing of MPS on cathode was studied by EIS and the results proposed to physical-chemistry adsorption in the plating formula. An optimal plating solution composed of CuSO4, H2SO4, chloride ions, PEP, MPS and JGB was obtained, and the microvia could be fully filled using the plating formula.

Article
Publication date: 29 July 2014

Shouxu Wang, Li Feng, Yuanming Chen, Wei He, Zhihua Tao, Shijing Chen and Huan Xu

The purpose of this paper is to form good cutting qualities in glass-epoxy material for opening flexible areas of rigid-flex printed circuit boards (PCB) by ultraviolet (UV) laser…

Abstract

Purpose

The purpose of this paper is to form good cutting qualities in glass-epoxy material for opening flexible areas of rigid-flex printed circuit boards (PCB) by ultraviolet (UV) laser cutting.

Design/methodology/approach

The cut width and cut depth of glass-epoxy materials were both observed to evaluate their cutting qualities. The heat affected zone (HAZ) of the glass-epoxy material was also investigated after UV laser cutting. The relationships between the cut width and the parameters of various factors were analyzed using an orthogonal experimental design.

Findings

The cut width of the glass-epoxy material gradually increased with the increment of the laser power and Z-axis height, while cutting speed and laser frequency had less effect on the cut width. Optimal parameters of the UV laser process for cutting glass-epoxy material were obtained and included a laser power of 6W, a cutting speed of 170 mm/s, a laser frequency of 50 kHz and a Z-axis height of 0.6 mm, resulting in an average cut width of 25 μm and small HAZ.

Originality/value

Flexible areas of rigid-flex PCBs are in good agreement with the cutting qualities of the UV laser. The use of a UV laser process could have important potential for cutting glass-epoxy materials used in the PCB industry.

Details

Circuit World, vol. 40 no. 3
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 16 August 2013

Yuanming Chen, Wei He, Guoyun Zhou, Zhihua Tao, Yang Wang and Daojun Luo

Pb‐free soldering challenged printed circuit board (PCB) assembly with high temperature. The purpose of this paper is to explain the failure mechanism of printed circuit board…

Abstract

Purpose

Pb‐free soldering challenged printed circuit board (PCB) assembly with high temperature. The purpose of this paper is to explain the failure mechanism of printed circuit board (PCB) assembly with solder bubbles of vias to avoid the problems of via‐drilling defects and solder joint failure.

Design/methodology/approach

The failure of PCB vias with solder bubbles was investigated through cross sections and SEM microstructure inspection, TMA measurement, moisture absorption analysis and DSC measurement. The moisture absorption and CTE of FR4 laminate matched with manufacturing requirement to avoid the effects of solder bubbles. The effects of via drilling with a dull drill bit were compared to that with a new drill bit.

Findings

The moisture absorbed inside holes of via plating layers could be exposed to induce solder bubbles during Pb‐free soldering assembly and dull drill bits should be prevented during the drilling process to avoid the no‐bearing drilling effects.

Originality/value

The failure of PCB vias is not only involved in the voiding in solder joints but manufacturing processes of PCB. The paper designs an approach to analyse the properties of PCB materials and the drilling effects of vias to find out the mechanism resulting in solder bubbles of vias. The problem of drill bits should be considered to prevent the moisture absorbed in drilling vias with defects.

Details

Circuit World, vol. 39 no. 3
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 29 April 2014

Guoyun Zhou, Chia-Yun Chen, Liyi Li, Zhihua Tao, Wei He and C.P. Wong

Nickel phosphorus (Ni−P) thin-films have been electrolessly deposited in an acid-plating bath with the addition of manganese sulfate monohydrate (MSM) to achieve higher resistance…

Abstract

Purpose

Nickel phosphorus (Ni−P) thin-films have been electrolessly deposited in an acid-plating bath with the addition of manganese sulfate monohydrate (MSM) to achieve higher resistance for the application of embedded resistor with value beyond 10 KΩ. As this material is being used for fabricating embedded resistors under the addition of MSM, its resistance properties including effects of MSM concentration and plating time on resistances, temperature coefficient of resistance (TCR), and resistance tolerance of embedded resistor were investigated. The paper aims to discuss these issues.

Design/methodology/approach

The structure of fabricated Ni−P film was detected by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The properties of substrate, including the surface morphologies, glass transition process and boundary of copper pad and substrate surface, were performed by SEM, dynamic mechanical analysis and optical microscope, respectively. The resistance tolerances of embedded resistors were elaborated from the cases of Ni−P thin-film resistance tolerance and the size effects of resistors, respectively.

Findings

The fabricated film was found to be constructed with numerous Ni−P amorphous nanoparticles, which was believed to be the reason of increasing thin-film resistance. The Ni−P thin-films presented over one magnitude order of resistance increasing in the case of MSM concentration varied from 0 to 40 g/L. For the case of TCRs, Ni−P thin-films deposited with 20 g/L MSM exhibited low TCRs of within ±100 ppm/°C Before TR at temperature elevating from 40 to 160°C, indicating that this Ni−P thin-film belongs to the constant TCR materials according to the military standard. For the tolerance of embedded resistor, the tolerance contributed by Ni−P thin-film was obtained to be 9.8 percent, whereas the geometry tolerances were in the range of 0-20 percent according to the geometries of embedded resistor.

Originality/value

For Ni−P thin-film without MSM, its low resistance with around 100 ohm/sq. limit the values of resistor few KΩ and restricted its widespread application of embedded resistor with higher resistance beyond 10 KΩ. The authors introduced MnSO4 in Ni−P electroless plating process to improve the low resistance of Ni−P thin-film. The resistance was increased over one order of magnitude after added with 40 g/L MnSO4. Due to the specific structure, as this material is being used for fabricating embedded resistors, the electrical properties and its application properties to verify its appliance in embedded resistor were systematically investigated by means of SEM, TEM, XRD characterizations, TCRs, resistance tolerance analysis, respectively.

Article
Publication date: 3 April 2020

Chengjing You

This paper aims to convict the offender of real concurrence offenses of the most severe offense and applying the most severe penalty will result in no distinction between the…

Abstract

Purpose

This paper aims to convict the offender of real concurrence offenses of the most severe offense and applying the most severe penalty will result in no distinction between the perpetrator who conducted more than one act and the one who conducted only one act. This approach deviates from the purpose of criminal law. The real concurrence of offenses means several offenses, the perpetrator’s dangerousness and culpability are much higher than the perpetrator who commits just one crime, so combined punishments for several offenses should be applied to the real concurrence of offenses.

Design/methodology/approach

If the depositors are acquaintances or relatives and friends, the relationship can be explained by “personality trust.” If the depositors are strangers, but they have complied with their duties of care, the deposit relationship can be explained by “system trust.”

Findings

The real concurrence of offenses means several offenses, the perpetrator’s dangerousness and culpability are much higher than the perpetrator who commits just one crime, so combined punishments for several offenses should be applied to the real concurrence of offenses.

Originality/value

The principle of choosing the most severe punishment applied to the real concurrence of offense should be abolished. As the perpetrator separately conducts two acts at different times, these acts infringe on different legal interests. Although these acts exist closely, the authors cannot deny that these acts constitute more than one offense.

Article
Publication date: 30 September 2019

Dan Zhao, Cun Xin, Tao Jin, Xiaopeng Yan, Shenggguo Ma and Zhihua Wang

The purpose of this study to analyze the plastic anisotropy of 6061 aluminum alloy with finite deformation using crystal plasticity finite element method.

Abstract

Purpose

The purpose of this study to analyze the plastic anisotropy of 6061 aluminum alloy with finite deformation using crystal plasticity finite element method.

Design/methodology/approach

A representative volume element (RVE) model was constructed by Voronoi tessellation. In this model, grain shapes, grain orientations and distribution of grains were involved. The mechanical response of the component under composite loading was tested using specify cruciform specimen. Moreover, different stress and strain states in the specific central region were analyzed to reveal the effects of complex loading.

Findings

We calculated the influence of misorientation of adjacent grains as well as the evolution of the micro structure’s plastic deformation on the macroscopic deformation of the structure. Geometry design for the cruciform specimen helps obtain a homogenous distribution of the stress and strain at the specimen center. In this process, the initial grain orientation is also an important factor, and the larger misorientations between special grains may cause greater stress concentration.

Originality/value

The influence of micro-scale factors on macro-scale plastic anisotropy of AA6061 is analyzed using RVE model and cruciform specimen, and they offer a reference for related research.

Details

Engineering Computations, vol. 37 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 7 August 2019

Zhihua Niu, Zhimin Li, Sun Jin and Tao Liu

This paper aims to carry out assembly variation analysis for mechanisms with compliant joints by considering deformations induced by manufactured deviations. Such an analysis…

Abstract

Purpose

This paper aims to carry out assembly variation analysis for mechanisms with compliant joints by considering deformations induced by manufactured deviations. Such an analysis procedure extends the application area of direct linearization method (DLM) to compliant mechanisms and also illustrates the dimensional interaction within multi-loop compliant structures.

Design/methodology/approach

By applying DLM to both geometrical equations and Lagrange’s equations of the second kind, an analytical deviation modeling method for mechanisms with compliant joints are proposed and further used for statistical assembly variation analysis. The precision of this method is verified by comparing it with finite element simulation and traditional DLM.

Findings

A new modeling method is proposed to represent kinematic relationships between joint deformations and parts/components deviations. Based on a case evaluation, the computational efficiency is improved greatly while the modeling accuracy is maintained at more than 94% rate comparing with the benchmark finite element simulation.

Originality/value

The Equilibrium Equations of Incremental Forces derived from Lagrange’s equations are proposed to quantitatively represent the relationships between manufactured deviations and assembly deformations. The present method extends the application area of DLM to compliant structures, such as automobile suspension systems and some Micro-Electro-Mechanical-Systems.

Details

Assembly Automation, vol. 39 no. 4
Type: Research Article
ISSN: 0144-5154

Keywords

Open Access
Article
Publication date: 7 June 2021

Saad Ahmed Javed, Yu Bo, Liangyan Tao and Wenjie Dong

Global supply chains experienced unprecedented changes in 2020 and the relationship between domestic and global markets needed adjustments considering the long-term impacts of the…

7614

Abstract

Purpose

Global supply chains experienced unprecedented changes in 2020 and the relationship between domestic and global markets needed adjustments considering the long-term impacts of the changes that are unfolding around these markets. China has become the first country to announce a formal strategy – “Dual Circulation” Strategy (DCS) – to guide its self-reliant economic development in the post-COVID era. However, what exactly is the DCS and what drove China to publicize this strategy is not yet clear. This study aims to answer these questions.

Design/methodology/approach

Based on an extensive review of literature and media reports, a background has been constructed that justifies the DCS as a long-overdue historic necessity.

Findings

A novel definition of “Dual Circulation” is introduced. A novel construct to visualize the domestic circulation in light of international and domestic markets and international circulation has been presented. The study argues that maintaining optimum levels of consumption and saving rates is crucial to the DCS’s success.

Originality/value

The study pioneers the first scientific definition of the “Dual Circulation” that will pave way for future debate on the topic. Also, it is the first time an academic study on the DCS has been executed.

Details

Rajagiri Management Journal, vol. 17 no. 1
Type: Research Article
ISSN: 0972-9968

Keywords

Article
Publication date: 18 October 2023

Sisi Zou and Catriona Paisey

The purpose of this paper is to examine the alternative accounts produced by Green Earth Volunteers (GEV), a Chinese environmental non-governmental organisation, over a 10-year…

Abstract

Purpose

The purpose of this paper is to examine the alternative accounts produced by Green Earth Volunteers (GEV), a Chinese environmental non-governmental organisation, over a 10-year period in the context of their campaign to create visibilities about hydroelectric dam projects along the Chang Jiang.

Design/methodology/approach

Drawing on conceptions of the human–nature relationship, including those evident in ancient Chinese philosophy and mythology, and the Chinese way of viewing and resolving conflict, this paper offers an interpretive analysis of the alternative accounts of GEV in terms of their form and content.

Findings

In terms of their content, the alternative accounts reflect elements of interrelated thinking, being underpinned by a recognition of the relationship between humans and nature, which is evident in Confucianism, Taoism and ancient Chinese mythology. The strategies adopted by GEV are a non-confrontational but feasible way to promote their ecological beliefs in the Chinese context.

Practical implications

The study suggests that social and environmental accounting (SEA) in developing countries is steeped in local cultural and philosophical traditions that need to be considered and incorporated into the design of alternative accounts.

Originality/value

The study contributes to the very limited literature that offers qualitative analyses of SEA in developing countries.

Details

Accounting, Auditing & Accountability Journal, vol. 37 no. 4
Type: Research Article
ISSN: 0951-3574

Keywords

Article
Publication date: 27 March 2024

Yupeng Mou, Yixuan Gong and Zhihua Ding

Artificial intelligence (AI) is experiencing growth and prosperity worldwide because of its convenience and other benefits. However, AI faces challenges related to consumer…

Abstract

Purpose

Artificial intelligence (AI) is experiencing growth and prosperity worldwide because of its convenience and other benefits. However, AI faces challenges related to consumer resistance. Thus, drawing on the user resistance theory, this study explores factors that influence consumers’ resistance to AI and suggests ways to mitigate this negative influence.

Design/methodology/approach

This study tested four hypotheses across four studies by conducting lab experiments. Study 1 used a questionnaire to verify the hypothesis that AI’s “substitute” image leads to consumer resistance to AI; Study 2 focused on the role of perceived threat as an underlying driver of resistance to AI. Studies 3–4 provided process evidence by the way of a measured moderator, testing whether AI with servant communication style and literal language style is resisted less.

Findings

This study showed that AI’s “substitute” image increased users' resistance to AI. This occurs because the substitute image increases consumers’ perceived threat. The study also found that using servant communication and literal language styles in the interaction between AI and consumers can mitigate the negative effects of AI-substituted images.

Originality/value

This study reveals the mechanism of action between AI image and consumers’ resistance and sheds light on how to choose appropriate image and expression styles for AI products, which is important for lowering consumer resistance to AI.

Details

Marketing Intelligence & Planning, vol. 42 no. 4
Type: Research Article
ISSN: 0263-4503

Keywords

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