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The impact strength of solder joint under high strain rate was evaluated by board level test method. However, the impact shear test of single solder bump was more convenient and economical than the board level test method. With the miniaturization of solder joints, solder joints were more prone to failure under thermal shock and more attention has been paid to the impact reliability of solder joint. But Pb-free solder joints may be paid too much attention and Sn-Pb solder joints may be ignored.

In this study, thermal shock test between −55°C and 125°C was conducted on Sn-37Pb solder bumps in the BGA package to investigate microstructural evolution and growth mechanism of interfacial intermetallic compounds (IMCs) layer. The effects of thermal shock and ball diameter on the mechanical property and fracture behavior of Sn-37Pb solder bumps were discussed.

With the increase of ball size, the same change tendency of shear strength with thermal shock cycles. The shear strength of the solder bumps was the highest after reflow; with the increase of the number of thermal shocks, the shear strength of the solder bumps was decreased. But at the time of 2,000 cycles, the shear strength was increased to the initial strength. Minimum shear strength almost took place at 1,500 cycles in all solder bumps. The differences between maximum shear strength and minimum shear strength were 9.11 MPa and 16.83 MPa, 17.07 MPa and 15.59 MPa in φ0.3 mm and φ0.4 mm, φ0.5 mm and φ0.6 mm, respectively, differences were increased with increasing of ball size. With similar reflow profile, the thickness of IMC decreased as the diameter of the ball increased. The thickness of IMC was 2.42 µm and 2.17 µm, 1.63 µm and 1.77 µm with increasing of the ball size, respectively.

Pb-free solder was gradually used to replace traditional Sn-Pb solder and has been widely used in industry. Nevertheless, some products inevitably used a mixture of Sn-Pb and Pb-free solder to make the transition from Sn-Pb to Pb-free solder. Therefore, it was very important to understand the reliability of Sn-Pb solder joint and more further research works were also needed.

With continuous concerning on the toxic of element Pb, Pb-free solder was gradually used to replace traditional Sn-Pb solder. However, during the transition period from Sn-Pb to Pb-free solder, mixing of Sn-Pb and Pb-free is inevitable occurred in certain products, and in China where Sn-Pb solder was still used extensively in certain areas especially. Correspondingly, understanding reliability of Sn-Pb solder joints was very important, and further studies were needed.

Thermal shock test between −55°C and 125 °C was conducted on Sn-37Pb solder bumps in the BGA package to investigate the microstructure evolution and the growth mechanism of interfacial intermetallic compound (IMC) layer. The effects of thermal shock on the mechanical property and fracture behavior of Sn-37Pb solder bumps were discussed.

Pb-rich phase was coarsened and voids were increased at first; Pb-rich phase was refined and voids were decreased secondly with the increase of thermal shock cycles; the shear strength of solder bumps was slightly decreased after thermal shock, but was back up to 73.67MPa at 2,000 cycles; interfacial IMCs of solder bumps was from typical scallop-type into smooth, the composition of IMCs was from Cu₆Sn₅ into Cu₆Sn₅ and Cu₃S_n after thermal shock with 1,500 and 2,000 cycles; 20.0 per cent of solder bumps at 1,500 cycles and 9.5 per cent of solder bumps at 2,000 cycles were failure respectively.

Compared with the board level test method, the impact shear test for the single solder bump is more convenient and economical and is actively pursued by the industries. The shear strength of solder bumps was slightly decreased after thermal shock, but was back up to 73.67 MPa at 2,000 cycles; 20.0 per cent of solder bumps at 1,500 cycles and 9.5 per cent of solder bumps at 2,000 cycles were failure.

This paper aims to offer a convenient method to develop an oven recipe for a specific soldering profile in a reflow process. The method is devised to quickly achieve proper profile shape and heating factor Q_η, a measure of success for high reliability of the solder joints reflowed.

An in‐depth analysis of the heating mechanism and some experiments of the reflow soldering process are performed to research on how to realize a specific shape reflow profile were conducted.

Heating mechanism analysis and experiments demonstrate that the combinatorial parameters based method is feasible to do thermal profiling.

The mapping function among a particular configured PCBA, an oven used, a target reflow profile and an optimal range of the heating factor should be further established for fast and reliable production of reflow soldering.

Provides a methodology for designing an oven recipe for reflow soldering production.

An oven recipe can be quickly attained with the approach established in this paper, facilitating the formation of solder joints with high reliability during the reflow soldering process.

The purpose of this paper is to accomplish the low cost mass‐production of flexible radio frequency identification (RFID) tag inlays.

An anisotropic conductive paste (ACP) is prepared by mixing uniform micro‐sized spherical conductive particles, latent curing agent and other additives into a thermoset epoxy resin. RFID tag inlays are assembled with the paste through flip‐chip technology. The microstructural analysis of bonded joints, bond strength testing, and high‐temperature and humidity aging testing are employed to evaluate the performance of the inlays.

It was found that the chips are hard assembled on the antennae by the ACP. Flexible RFID tag inlays assembled using the presented method have good reliability when working under high frequency (13.56 MHz) conditions.

The method presented is a promising new way for packaging flexible RFID tag inlays with ACP. Through the use of flip‐chip technology, large‐scale production is possible with low manufacturing costs.

The paper details a simple way to prepare an anisotropic conductive paste and to assemble flexible RFID tag inlays. The technique uses flip‐chip technology with the paste as the electrical and mechanical interconnection material. It presents a simple and fast method of assembly for flexible RFID tag inlays on a large‐scale with low cost.

Knowledge-based organizations is a new paradigm for business. Knowledge management (KM) is important for supporting core business processes. This paper aims to define an open innovation (OI)-driven KM implementation for effectively executing the support.

KM is important for supporting organizational innovation. OI plays a critical determinant role in defining the design of KM for effectively supporting OI. Further, the final goal of KM is to reach the success of OI-based KM implementation. A model is thus proposed for connecting OI as a driver to a design of KM and, in turn, KM implementation. Survey is conducted to collect data. Partial least squares is used for analysis.

The three processes of OI partially present significant impact on the design of KM process and, in turn, a noticeable achievement of KM implementation. The two KM processes indicate an interaction effect for reinforcement mutually. The findings provide rich evidence into the argument that OI-based KM implementation through the mediator of the design of KM process is important for a successful KM in organizations.

While OI is a phenomenon that has increasingly become critical for the contemporary business, the design of KM mechanism needs to be adapted from the choice of OI process for guaranteeing the success of KM implementation.

Extant theories did not provide such an approach to develop an effective KM implementation in terms of the important management concept, OI, in organizations. This model empirically demonstrates its capability to work on this issue.

This chapter aims to delineate the indigenous pattern of parental involvement in Taiwan by investigating the effects of specific practices in schools and in the family, such as school selection, school involvement, preparing a study place at home, and providing nutritious food.

We use two waves of data from the Taiwan Youth Project (2000, 2003) to examine how parental involvement varies between dual- and single-earner families, and we further demonstrate how sons and daughters have different access in terms of recognizing their parents’ effort, and how children’s subjective appraisals promote their academic performance with respect to test scores.

We find that dual-earner families have higher incomes, higher educational levels, and have fewer children than single-earner ones. Our multivariate analyses show that parental involvement does increase youngsters’ Basic Competence Test (BCT) score. However, we are unable to find any direct or indirect effects from parental employment status on BCT scores. Further analysis indicates that the relationship between parental school involvement and BCT score is only significant among dual-earner families, but not for the single-earner ones. In addition, our multiple group analysis reveals that sons’ BCT scores are affected more by parents’ school involvement, whereas daughters’ are affected more by special home provision. Our findings from adolescents’ subjective responses imply that sons may be more responsive to a non-familial context in contrast with daughters, who react more positively to familial provision.

An increasing number of users join and become immersed in WeChat official accounts, but many users quit using these services as well. Nevertheless, most of the previous studies mainly focussed on the usage behavior. The purpose of this paper is to fill the gap by examining factors affecting users’ unfollow intentions for WeChat subscriptions in a Chinese context.

Structural equation modeling is used in our study. A field survey with 260 WeChat users is conducted to test the research model and hypotheses.

The results show the following interesting key findings: first, the effect of actual cost on users’ unfollow intentions is larger than the effect of opportunity cost; second, users’ unfollow intentions will decrease with the increase of users’ perceptions of information usefulness; third, the results of the control variables showed that only landing frequency has a negative effect on users’ unfollow intentions; and fourth, users’ demographic differences are also examined in regard to how they may affect users’ unfollow intentions.

First, this paper studies factors influencing users’ unfollow intentions for WeChat subscriptions from a social exchange theory perspective; the authors considered both extraneous factors and users’ internal perception factors potentially affecting users’ unfollow intentions, which has rarely been researched. Furthermore, the authors examined significant differences among users’ demographic characteristics in affecting users’ unfollow intentions. The results of the study provide a more comprehensive understanding of the influencing factors of users’ unfollow intentions.

The paper aims to propose a model and a comprehensive diagnostic method of organizational health status based on traditional Chinese medicine (TCM).

The methodology is qualitative/interpretive and uses of the concept of functional homomorphism of WR Ashby is used, establishing similarities between the way in which this ancient medicine considers the human being and their condition as healthy to transfer it to an organization that produces goods and/or services.

A healthy organization is conceived as one constituted by an association of people regulated by a set of norms based on certain purposes in a state of harmonious balance of their physical and energetic dimensions. In that the physical refers to storage functions, regulation and allocation of resources; transformation of raw materials and inputs into goods and services; waste disposal, distribution and coordination and with information systems for management control, while energy is associated with the ability to act with its management and policies.

The current paper is a first theoretical proposal, which should be enriched with practical applications that feedback its conceptual formulation, thus contributing to its validation.

A comprehensive organizational diagnostic method is made available.

The proposed method allows a comprehensive organizational diagnosis, considering the participation of all the actors that make up this type of social systems.

Although the methodological resource is old, the way it is used here is considered original, and it is also part of an original investigative process by the authors, oriented toward the search for comprehensive organizational diagnostic methods.

In response to the tilted emphasis on the corporate political activities and to the recent call for including the institutional perspective in the research of the MNE’s governmental relations (MGRs), this study aims to, departing from resource dependence theory, introduce the legitimacy formation as a bridging mechanism to MGRs to holistically examine the behavioral types of antecedents of MGRs in contingency with three critical contextual influences.

This study purposely chose a Taiwanese globalized logistic corporation that we have been acquainted with as the entry for collecting data. The study started the survey with the seven foreign subsidiaries of this logistic corporation and invited their customers through their personal referrals to join this survey. Following the snowball sampling, remarks were added in the questionnaire to request respondents’ assistance in inviting TMT members of different MNE subsidiaries in their personal networks to join the survey.

The findings from analyzing a survey data set of 155 MNE subsidiaries during 2016 show that the MNE’s economically-good behaviors are not so influential as Milton Friedman stated in 1962, and can only outperform socially-good and politically-good behaviors in shaping better MGRs under some specific contextual influences.

This study contributes to the international business literature by shedding new light on the sensitivity of behavioral antecedents of MGRs in contingency with contextual influences and provides managerial implications to MNE particularly when they expect to reduce external uncertainties or capturing opportunities by MGRs.