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Indium solders are frequently used for interconnections in cooled systems because of their high ductility down to very low temperatures. Very fine contact pitches are required for hybrid mosaic radiation sensors compared with those for conventional flip‐chip technology. This paper presents solutions for bumping and bonding indium bumps based on the measured properties of indium solders in relation to the requirements of, and possibilities for, manufacture of fine pitch solder bump features.

The purpose of this paper is to fit Coffin‐Manson equation of Sn‐4.0Ag‐0.5Cu lead free solder joint by using results of solders joint reliability test and finite element analysis. Also to present a novel device for solder joint reliability test.

Two‐points bending test of Sn‐4.0Ag‐0.5Cu lead free solder joint was carried out at three deflection levels by using a special bending tester that can control displacement exactly by a cam system. The failure criterion was defined as resistance of solder joint getting 10 percent increase. The X‐section was done for all failure samples to observe crack initiation and propagation in solder joint. Finite element analysis was presented with ANSYS for obtaining shear strain range, analyzing distribution of stress and strain and supporting experimental results.

The experimental results indicate that the fatigue life decreased obviously with the displacement increased. By using optical microscope and SEM photographs, two kinds of failure mode were found in solder joint. The majority failure mode took place at the bottom corner of solder joint under the termination of resistor initially, and propagated into the solder matrix. Another failure mode was delamination. It appeared at the interface between the termination of resistor and its ceramic body. The distribution status of stress and strain in solder joint and the calculation results of shear strain range at different deflection levels were obtained from simulation result. The Coffin‐Manson equation of Sn‐4.0Ag‐0.5Cu lead free solder joint was fitted by combining experimental data with result of finite element analysis.

This paper presents Coffin‐Manson equation of Sn‐4.0Ag‐0.5Cu solder joint with two‐points bending test. An effective and economical device was designed and applied.

In land grid array hybrid or system in package type products passive integration on silicon dies are flip chip mounted on a laminate substrate using Pb‐free solder. To increase the solder bump fatigue life, underfill is applied. The application of underfill resulted in the occurrence of an unexpected and unwanted phenomenon: solder flowing out of the underfill during a second level reflow test. The occurrence of solder flow‐out seemed associated with moisturizing as part of a moisture sensitivity level assessment. The solder flow‐out is preceded by delamination, initiated by mismatch in coefficient of thermal expansion between copper through‐holes and laminate. This paper aims to describe the phenomenon and possible solutions by combining experiments with finite element (FE) simulations.

Ways to prevent this kind of overstress failures are investigated by design of experiments and observed trends are compared with thermo‐mechanical FE simulations. A significant contribution is made by through‐holes close to the bump and underfill fillet.

The FE simulations confirmed increased thermo‐mechanical induced stress levels by bad positioning of vias, underfill and solder. The integrity of the flip chip construction is substantially improved by optimising product design, underfill material and the associated assembly process.

This paper is a useful source of information on the causes of delamination and solder flow‐out.

There are several lead-free solder alloys available in the industry. Over the years, the most favorable solder composition of tin-silver-copper (Sn-Ag-Cu [SAC]) has been vastly used and accepted for joining the electronic components. It is strongly believed that the silver (Ag) content has a significant impact on the solder mechanical behavior and thus solder thermal reliability performance. This paper aims to assess the mechanical response, i.e. creep response, of the SAC solder alloys with various Ag contents.

A three-dimensional nonlinear finite element simulation is used to investigate the thermal cyclic behavior of several SAC solder alloys with various silver percentages, including 1%, 2%, 3% and 4%. The mechanical properties of the unleaded interconnects with various Ag amounts are collected from reliable literature resources and used in the analysis accordingly. Furthermore, the solder creep behavior is examined using the two famous creep laws, namely, Garofalo’s and Anand’s models.

The nonlinear computational analysis results showed that the silver content has a great influence on the solder behavior as well as on thermal fatigue life expectancy. Specifically, solders with relatively high Ag content are expected to have lower plastic deformations and strains and thus better fatigue performance due to their higher strengths and failure resistance characteristics. However, such solders would have contrary fatigue performance in drop and shock environments and the low-Ag content solders are presumed to perform significantly better because of their higher ductility.

Generally, this research recommends the use of SAC solder interconnects of high silver contents, e.g. 3% and 4%, for designing electronic assemblies continuously exposed to thermal loadings and solders with relatively low Ag-content, i.e. 1% and 2%, for electronic packages under impact and shock loadings.

Amidst the turbulent tides of geopolitical uncertainty and pandemic-induced economic disruptions, the information technology industry grapples with alarming attrition and aggravating talent gaps, spurring a surge in demand for specialized digital proficiencies. Leveraging this imperative, firms seek to attract and retain top-tier talent through generous compensation packages. This study introduces a holistic, integrated theoretical framework integrating machine learning models to develop a compensation model, interrogating the multifaceted factors that shape pay determination.

Drawing upon a stratified sample of 2488 observations, this study determines whether compensation can be accurately predicted via constructs derived from the integrated theoretical framework, employing various cutting-edge machine learning models. This study culminates in discovering a random forest model, exhibiting 99.6% accuracy and 0.08° mean absolute error, following a series of comprehensive robustness checks.

The empirical findings of this study have revealed critical determinants of compensation, including but not limited to experience level, educational background, and specialized skill-set. The research also elucidates that gender does not play a role in pay disparity, while company size and type hold no consequential sway over individual compensation determination.

The research underscores the importance of equitable compensation to foster technological innovation and encourage the retention of top talent, emphasizing the significance of human capital. Furthermore, the model presented in this study empowers individuals to negotiate their compensation more effectively and supports enterprises in crafting targeted compensation strategies, thereby facilitating sustainable economic growth and helping to attain various Sustainable Development Goals.

The cardinal contribution of this research lies in the inception of an inclusive theoretical framework that persuasively explicates the intricacies of a machine learning-driven remuneration model, ennobled by the synthesis of diverse management theories to capture the complexity of compensation determination. However, the generalizability of the findings to other sectors is constrained as this study is exclusively limited to the IT sector.

Because of the need for electronics use at temperatures beyond 150°C, high temperature resistant interconnection technologies like transient liquid phase (TLP) soldering and silver sintering are being developed which are not only replacements of high-lead solders, but also open new opportunities in terms of temperature resistance and reliability. The paper aims to address the thermo-mechanical reliability issues that have to be considered if the new interconnection technologies will be applied.

A TLP soldering technique is briefly introduced and new challenges concerning the thermo-mechanical reliability of power devices are worked out by numerical analysis (finite element simulation). They arise as the material properties of the interconnect materials differ substantially from those known for soft solders. The effective material responses of the new materials are determined by localized unit cell models that capture the inhomogeneous structure of the materials.

It is shown that both the TLP solder layer and the Ag-sinter layer have much less ductility and show less creep than conventional soft solders. The potential failure modes of an assembly made by TLP soldering or Ag sintering change. In particular, the characteristic low cycle fatigue solder failures become unlikely and are replaced either by metallization fatigue, brittle failure of intermetallic compound, components, or interfaces.

A variety of new failure risks, which have been analyzed theoretically, can be avoided only if they are known to the potential user of the new techniques. It is shown that an optimal reliability will be strongly dependent on the actual assembly design.

This paper aims to determine the influence of various enterprise characteristics on on-the-job training. The paper focuses mainly on identifying the influence of a firm’s innovative activity, technological capacity for manufacturing and product market competition on its likelihood of having a training program and on training intensity.

The authors administered a firm-level survey to a sample of 2,000 Russian enterprises. This survey includes questions about on-the-job training and key information about the companies’ activities. Probit and ordered probit estimates are used in the statistical analyses.

The results indicate that an enterprise’s provision of training is determined largely by firm-specific factors, such as its innovative activity, technical and technological state of manufacturing and product market competition. The authors adopt two widely used measures of training: incidence and intensity. Innovative activity and the technical and technological state of manufacturing are decisive factors in explaining a firm’s provision of training, as they have a strictly positive effect on both the incidence and the intensity of training. Product market competition has a positive effect on the incidence of training and a negative effect on the intensity of training.

This paper is original because it assumes that the process of deciding whether to implement a training program at an enterprise and the corresponding proportion of employees involved in training is built on the presupposition that the training intensity decision is made in two stages. This paper is the first to present estimates of on-the-job training intensity based on data from Russian enterprises.

The lifetime of flip chip solder joints can be greatly increased by applying underfill encapsulation. This paper presents a case study where the thermal cycle lifetime was increased by more than 20 times, that is from ∼100 cycles to more than 2,000 cycles for a chip size of 5.6mm × 6.3mm. By combining electrical, acoustic and metallographic investigation, the degradation of the solder joints was monitored, some important factors relevant to solder joint reliability were analysed and discussed. Delamination was found not to be the dominant failure mode.

The purpose of this paper is to detail various aspects of laminates and their current developments in order to enable the selection and development of appropriate laminate systems for use in high performance avionics interconnection applications.

Electronic packaging must provide circuit support, heat dissipation, signal distribution, manufacturability, serviceability, power distribution and data for performance simulation over the required frequency range in avionics applications. Innovations in packaging technology have made a big impact on the types of laminates that can be used in printed circuit boards destined for these applications. The “environments” in which aircraft are required to operate have changed due to global security threats and the laminates traditionally used are not designed for this role. Aircraft systems are expected to withstand disturbances due to unexpected threats. Various factors which determine the performance of laminates are evaluated.

The safety of aircraft is critically dependent on the interconnection technology in which laminates have a major role. Under global security threats, passenger safety, emergency landing and timely information to the pilot is of paramount importance. Hence, research programs need to be initiated to develop new innovative laminate systems, since traditional laminates have limitations in these applications.

The availability of data on the performance of laminates used in interconnection technology under various security threats is limited.

The paper describes how new laminates for high performance interconnection technology in avionics applications can be developed.

This paper aims to understand the development track of skills mismatch research and discover the hidden internal connections between literature.

The authors gathered data through scientometric quantitative analysis using CiteSpace. Specifically, this article applied basic analysis, journal cocitation analysis (JCA), author cocitation analysis (ACA) and document cocitation analysis (DCA), cluster analysis, citation burstness detection, scientific research cooperation analysis and coconcurrence analysis of keywords of 3,125 documents from Web of Science core collections for the period 2000–2020.

Through the document cocitation analysis and the keywords' co-occurrence, this article identifies influential scholars, documents, research institutions, journals and research hotspots in research on the skills mismatch phenomenon. The results showed that the publications had ballooned, and the phenomenon has become an interdisciplinary research subject. The USA and Finland remain the main contributors, which is attributed to their high-yield institutions such as the University of Helsinki, the University of Witwatersrand, the University of Washington and so on. While the African continent lacks research on skills mismatch even with the continent’s effort to overcome such a crucial issue. The paper presents an in-depth analysis of skills and educational mismatch issues to better understand the evolutionary trajectory of the collective knowledge over the past 20 years and highlight the areas of active pursuit.

The authors only used Web of Science core collection to collect data; however, they can added Scopus indexed database as well to extend the research trends and explore more new research hot topics to solve the skills mismatch phenomenon.

The scientometric analysis is of great significance for identifying the potential relationship between the literature and investigating the knowledge evolution of skills mismatch research. Organisation for Economic Co-operation and Development, the International Labor Organization and the World Health Organization are the giants who are mostly concerned of the mismatch skills phenomenon. Researchers can refer to this study to understand the status quo, gaps and research trends to deal with the skills mismatch issue.