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Anisotropic conductive film (ACF) offers miniaturization of package size, reduction in interconnection distance and high performance, cost‐competitive packaging and improved environmental impact. However, a major limitation for ACF is the instability caused by thermal warpage. The purpose of this paper is to study the effects of thermal warpage on contact resistance in real time i.e. make online measurements of contact resistance fluctuations while the assembly undergoes thermal shock.

The ACF assemblies are subjected to thermal cycling with different temperature profiles that have peak temperatures either below or above the glass transition temperature (T_g) of the ACF. The flex substrate used was made of polyimide film, with Au/Ni/Cu electrodes and a daisy‐chained circuit matched to the die bump pattern. The ACF used was based on epoxy resin in which nickel and gold‐coated polymer particles are dispersed. A comparative study was carried out on the results obtained.

The results showed that the glass transition temperature (T_g) of the ACF material plays an important role in the high temperature contact resistance. Above T_g, the ACF matrix becomes less viscous, which reduces its adhesive strength and allows the bumps on the chip to slide away from the pads on the substrate. Even though a flex substrate was used in this study, the sliding effect is severe at the corner bumps of the chip, where cumulative forces are generated due to the thermal expansion mismatch. For every thermal cycling profile, there is an incubation period encountered from this work that would have a significant impact in the application of ACF. After the incubation period the contact resistance increased rapidly and the assemblies were therefore no longer reliable.

The work in this paper focuses on contact resistance changes during thermal shock. The paper discusses the reliability issue of ACF during thermal warpage, which is useful to industries using ACF for flip‐chip assemblies.

The curing reaction of a promising “no flow” flip chip underfill encapsulant is investigated by using a differential scanning calorimeter. It is found that the tested underfill can reach complete cure within 20 minutes at various cure temperatures. It is also shown that this “no flow” underfill could fully cure within one minute at 160°C after being heated at 220°C for one minute, demonstrating that this “no flow” underfill can be completely cured during the solder reflow cycle. The reaction order and the rate constant are determined to describe the curing progress. It is shown that the autocatalytic effect dominates the reaction kinetics.

The purpose of this paper is to assess the thermo-mechanical reliability of a solder bump with different underfills, with the evaluation of different underfill materials. As there is more demand in higher input/output, smaller package size and lower cost, a flip chip mounted at the module level of a board is considered. However, bonding large chips (die) to organic module means a larger differential thermal expansion mismatch between the module and the chip. To reduce the thermal stresses and strains at solder joints, a polymer underfill is added to fill the cavity between the chip and the module. This procedure has typically, at least, resulted in an increase of the thermal fatigue life by a factor of ten, as compared to the non-underfilled case. Yet, this particular case is to deal with a flip chip mounted on both sides of a printed circuit board (PCB) module symmetrically (solder bump interconnection with Cu-Pillar). Note that Cu-Pillar bumping is known to possess good electrical properties and better electromigration performance. The drawback is that the Cu-Pillar bump can introduce high stress due to the higher stiffness of Cu compared to the solder material.

As a reliability assessment, thermal cyclic loading condition was considered in this case. Thermal life prediction was conducted by using finite element analysis (FEA) and modified Darveaux’s model, considering microsize of the solder bump. In addition, thermo-mechanical properties of four different underfill materials were characterized, such as Young’s modulus at various temperatures, coefficient of temperature expansion and glass transition temperature. By implementing these properties into FEA, life prediction was accurately achieved and verified with experimental results.

The modified life prediction method was successfully adopted for the case of Cu-Pillar bump interconnection in flip chip on the module package. Using this method, four different underfill materials were evaluated in terms of material property and affection to the fatigue life. Both predicted life and experimental results are obtained.

This study introduces the technique to accurately predict thermal fatigue life for such a small scale of solder interconnection in a newly designed flip chip package. In addition, a guideline of underfill material selection was established by understanding its affection to thermo-mechanical reliability of this particular flip chip package structure.

We empirically assessed the antecedents of subjective well-being at work for French permanent employees.

The methodology includes qualitative and quantitative data analyses. In the first phase, interviews elicited the antecedents of subjective well-being at work among permanent French employees. In the second phase, a questionnaire survey was used to confirm the relevance of the antecedents uncovered in the first phase.

We found 14 distinct elements that influence French employees’ subjective well-being at work: corporate culture, job dissonance, relationships with colleagues, achievement, professional development, relationships with superiors, status, workload, perks, feedback, workspace, diversity and pay. Moreover, we identified discrete antecedents for the three components of subjective well-being at work: work achievement and relationships with superiors and colleagues for positive emotions at work, job dissonance and workload for negative emotions at work and organizational culture and professional development for satisfaction with one’s work.

The original contribution of this study is to have unpacked the black box of the antecedents of subjective well-being in the French workplace and to have uncovered discriminant predictors for each of the three components of subjective well-being at work. Furthermore, we specifically linked each of these three components with their most significant antecedents.

This paper aims to find proper technological parameters of low-temperature joining technique by silver sintering to eventually use this technique for reliable electronic packaging.

Based on the literature and author’s own experience, the factors influencing the nanosized Ag particle sintering results were identified, and their significance was assessed.

It has been shown that some important technological parameters clearly influence the quality of the joints, and their choice is unambiguous, but the meaning of some parameters is dependent on other factors (interactions), and they should be selected experimentally.

The value of this research is that the importance of all technological factors was analyzed, which makes it easy to choose the technological procedures in the electronic packaging.

The purpose of this paper is to identify factors behind cyclical fluctuations and differences in adjustments to shocks in Greece, Italy, Portugal and Spain (GIPS) and a reference country – Germany. The authors try to answer the question whether the GIPS countries could have fared differently in the Great Recession if they reacted to shocks affecting them like a resilient German economy would have.

The authors use a DSGE model of real open economy with search and matching on the labour market and endogenous job destruction, estimated separately for each country. The authors calculate impulse response functions, historical decompositions and perform counterfactual simulations of the response of the German model to the sequence of shocks identified for each of GIPS.

The authors find that all GIPS countries were more vulnerable to productivity and foreign demand shocks than Germany. They would have experienced lower macroeconomic volatility if they reacted to their shocks like Germany. Employment (unemployment) rates in GIPS would have been less volatile and higher (lower) during the Great Recession, especially in Spain and Greece. Real wage volatility would have been higher, especially in Spain and Portugal.

The trade-off between unemployment and wage adjustments vis-à-vis Germany was the largest in Spain, which also would have experienced lower variability of job separations and hirings. The evolution of the labour market in Greece and Portugal was driven rather by its higher responsiveness to GDP fluctuations than in Germany, whereas Italy emerges as the least responsive labour market within GIPS.

This paper aims to categorize users of voice assistants and analyze decision-making conflicts to predict intention to adopt voice commerce (v-commerce).

This exploratory study used expert survey-based data collection founded on data saturation.

This study identifies three forms of voice systems based on senses aroused (screen first, voice only and voice first) and four profiles of voice users (passive resistant, hedonistic adopter, utilitarian adopter and active resistant), each with a different appraisal of the benefits and costs of v-commerce adoption and the experiences (positive or negative) felt during the shopping experience. This study proposes a conceptual model to predict intention to adopt v-commerce depending on voice-system and -user characteristics.

Learning from this study can help improve the marketing strategies and actions put in place by voice-assistant brands and advertisers by providing insights for adapting product recommendation algorithms to meet the needs of the identified profiles.

This paper provides an answer to the limits of classical approaches based on “one-size-fits-all” strategy by showing how voice-assistant users have different profiles that span a gradient of advance in technology adoption.

In light of the new way of interpreting work spearheaded by Generation Z, the objectives of this study are to investigate (1) whether young entrepreneurs identify their start-ups with “zebras” – that is, as a concrete response to the evanescence and fantasy of “unicorns” based on the simultaneous pursuit of profit and social value, mutualism and resilience – and (2) whether they adopt a “teal” organizational configuration – that is, one characterized by evolutionary purpose, self-management and wholeness.

Through a qualitative approach with 41 interviews, this study focuses on start-uppers and companies that are particularly innovative and promising in the Italian context, as selected by Forbes magazine in its ranking of the brightest entrepreneurs, leaders and stars under 30.

The results suggest that young entrepreneurs recognize the importance of the common themes of the zebra movement and therefore identify their startups with zebras. More specifically, Generation Z entrepreneurs: (1) pursue a dual (economic and social) purpose, (2) are mutualistic and (3) build their organizations with resilience and capital efficiency. In addition, the interviews show that the organizational approach taken follows the paradigm of teal organizations, particularly in terms of evolutionary purpose, distributed leadership and decision-making power, and employee wholeness and empowerment.

This is the first study to analyze the evolutionary trends of animal entrepreneurial “species” led by Generation Z entrepreneurs and organized on the basis of the teal paradigm.

This study aims to examine the influence of the derived attributes of embedded artificial intelligence-mobile smart speech recognition (AI-MSSR) technology, namely perceived usefulness, perceived ease of use (PEOU) and perceived enjoyment (PE) on consumer purchase intention (PI) through the chain relationships of attitudes to AI and consumer smart experience, with the moderating effect of consumer innovativeness and Generation (Gen) X and Gen Y in fashion retail.

The study employed a quantitative survey strategy, drawing a sample of 836 respondents from Sri Lanka and India representing Gen X and Gen Y. The data analysis was carried out using smart partial least squares structural equation modelling (PLS-SEM).

The findings show a positive relationship between the perceived attributes of MSSR and consumer PI via attitudes towards AI (AAI) and smart consumer experiences. In addition, consumer innovativeness and Generations X and Y have a moderating impact on the aforementioned relationship. The theoretical and managerial implications of the study are discussed with a note on the research limitations and further research directions.

To multiply the effects of embedded AI-MSSR and consumer PI in fashion retail marketing, managers can develop strategies that strengthen the links between awareness, knowledge of the derived attributes of embedded AI-MSSR and PI by encouraging innovative consumers, especially Gen Y consumers, to engage with embedded AI-MSSR.

This study advances the literature on embedded AI-MSSR and consumer PI in fashion retail marketing by providing an integrated view of the technology acceptance model (TAM), the diffusion of innovation (DOI) theory and the generational cohort perspective in predicting PI.

The rapid growth of artificial intelligence (AI)-based voice-assistant systems (VASs) has created many opportunities for individuals to use VASs for various purposes in their daily lives. However, traditional quality success factors, such as information quality and system quality, may not be sufficient in explaining the adoption and use of AI-based VASs. This study aims to propose interaction quality as an additional, yet more important quality measure that leads to trust in an AI-based VAS and its adoption.

The authors propose a research model that highlights the importance of interaction quality and trust as underlying mechanisms in the adoption of AI-based VASs. Based on survey methodology and data from 221 respondents, the proposed research model is tested with a partial least squares approach.

The results suggest that interaction quality and trust are critical factors influencing the adoption of AI-based VASs. The findings also indicate that the impacts of traditional quality factors (i.e. information quality and system quality) occur through interaction quality in the context of AI-based VASs.

This research adds interaction quality as a new quality factor to the traditional quality factors in the information systems success model. Further, given the interactive nature of VASs, the authors use social response theory to explain the importance of the trust mechanism when individuals interact with AI-based VASs.