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The study aims to ascertain the influence of solder conductive particle types and substrate widths on the current carrying capability of flex-on-board (FOB) assemblies. By comparing Sn58Bi and SAC305 particles and varying substrate widths, the research sought to provide insights into the stability and performance of solder joints under different scenarios, particularly in high-power applications.

The study used a comprehensive design/methodology, encompassing the investigation of solder conductive particle types (Sn58Bi and SAC305) and substrate widths on the current carrying capability of FOB assembly. Stable solder joints were obtained by manipulating the curing speed of anisotropic conductive films for both particle types. Various tests were conducted, including current carrying capability assessments under differing conditions.

The study revealed that larger substrate widths yielded higher current carrying capability due to increased contact area and reduced contact resistance. Notably, solder joints remained stable beyond the solder melting temperature due to encapsulation by cured epoxy resin. SAC305 solder joints exhibited superior current carrying capability over Sn58Bi in continuous high-voltage conditions. The results emphasized the stability of SAC305 solder joints and their suitability for robust interconnections in high-power FOB assemblies.

This study contributes by offering a comprehensive assessment of the impact of solder particle types and substrate widths on solder joint performance in FOB assemblies. The finding that SAC305 joints outperform Sn58Bi under continuous high-voltage conditions adds significant value. Moreover, the observation of stable solder joints beyond solder melting temperature due to resin encapsulation introduces a novel aspect to solder joint reliability. These insights provide valuable guidance for designing robust and high-performance interconnections in demanding applications.

The purpose of this paper was to investigate how variations in the geometry of silicon chips and the presence of surface defects affect their static bending properties. By comparing the bending radius and strength across differently sized and treated chips, the study sought to understand the underlying mechanics that contribute to the flexibility of silicon-based electronic devices. This understanding is crucial for the development of advanced, robust and adaptable electronic systems that can withstand the rigors of manufacturing and everyday use.

This study explores the impact of silicon chip geometry and surface defects on flexibility through a multifaceted experimental approach. The methodology included preparing silicon chips of three distinct dimensions and subjecting them to thinning processes to achieve a uniform thickness verified via scanning electron microscopy (SEM). Finite element method (FEM) simulations and a series of four-point bending tests were used to analyze the bending flexibility theoretically and experimentally. The approach was comprehensive, examining both the intrinsic geometric factors and the extrinsic influence of surface defects induced by manufacturing processes.

The findings revealed a significant deviation between the theoretical predictions from FEM simulations and the experimental outcomes from the four-point bending tests. Rectangular-shaped chips demonstrated superior flexibility, with smaller dimensions leading to an increased bending strength. Surface defects, identified as critical factors affecting flexibility, were analyzed through SEM and atomic force microscopy, showing that etching processes could reduce defect density and enhance flexibility. Notably, the study concluded that surface defects have a more pronounced impact on silicon chip flexibility than geometric factors, challenging initial assumptions and highlighting the need for defect minimization in chip manufacturing.

This research contributes valuable insights into the design and fabrication of flexible electronic devices, emphasizing the significant role of surface defects over geometric considerations in determining silicon chip flexibility. The originality of the work lies in its holistic approach to dissecting the factors influencing silicon chip flexibility, combining theoretical simulations with practical bending tests and surface defect analysis. The findings underscore the importance of optimizing manufacturing processes to reduce surface defects, thereby paving the way for the creation of more durable and flexible electronic devices for future technologies.

The purpose of this study is to investigate the reliability of flex-on-board (FOB) interconnection connected with an anisotropic conductive paste (ACP), which is prepared by dispersing nickel balls in the epoxy-curing system.

Differential scanning calorimetry was used to evaluate the curing characteristics of the paste. And the contact resistances of bonding joints and 90º peel adhesion were tested before and after high temperature and high humidity test (85°C, 85% humidity), thermal cycling (−45°C∼125°C, 30min/cycle) and pressure cooker test (PCT, 121°C, 100% humidity 2 atm) to evaluate the flex on board (FOB) interconnection reliability.

It is found that FOB test vehicles have been successfully bonded by using ACP for the first time. And the ACP bonding joint of FOB has good reliability and can meet the requirements of FOB interconnection. Compared with conventional anisotropic conductive film (ACF), this ACP interconnection provides higher adhesion strength, higher joint current carrying capability and higher reliability performance and lower cost for FOB interconnection.

ACP is applied in the interconnection of FOB. It has the higher reliability performance and lower cost for than the conventional ACF.

In flip‐chip interconnection on organic substrates using eutectic tin/lead solder bumps, a highly reliable under bump metallurgy (UBM) is required to maintain adhesion and solder wettability. Various UBM systems such as 1μm Al/0.2μm Ti/5μm Cu, 1μm Al/02μm Ti/1μm Cu, 1μm Al/0.2μm Ni/1μm Cu and 1μm Al/0.2μm Pd/1μm Cu, applied under eutectic tin/lead solder bumps, have been investigated with regard to their interfacial reactions and adhesion properties. The effects of the number of solder reflow cycles and the aging time on the growth of intermetallic compounds (IMCs) and on the solder ball shear strength were investigated. Good ball shear strength was obtained with 1μm Al/0.2μm Ti5μm Cu and 1μm Al/0.2μm Ni/1μm Cu even after four solder reflows or seven‐day aging at 150∞C. In contrast, 1μm Al/0.2μm Ti/1μm Cu and 1μm Al/0.2μm Pd/1μm Cu showed poor ball shear strength. The decrease of the shear strength was mainly due to the direct contact between solder and non‐wettable metals such as Ti and AL, resulting in a delamination. In this case, thin 1μm Cu and 0.2μm Pd diffusion barrier layers were completely consumed by Cu‐Sn and Pd‐Sn reaction.

When wearable and implantable devices first arose in the 1970s, they were rigid and clashed dramatically with our soft, pliable skin and organs. The past two decades have witnessed a major upheaval in these devices. Traditional electronics are six orders of magnitude stiffer than soft tissue. As a result, when rigid electronics are integrated with the human body, severe challenges in both mechanical and geometrical form mismatch occur. This mismatch creates an uneven contact at the interface of soft-tissue, leading to noisy and unreliable data gathering of the body’s vital signs. This paper aims to predict the role that discreet, seamless medical devices will play in personalized health care by discussing novel solutions for alleviating this interface mismatch and exploring the challenges in developing and commercializing such devices.

Since the form factors of biology cannot be changed to match those of rigid devices, conformable devices that mimic the shape and mechanical properties of soft body tissue must be designed and fabricated. These conformable devices play the role of imperceptible medical interfaces. Such interfaces can help scientists and medical practitioners to gain further insights into the body by providing an accurate and reliable instrument that can conform closely to the target areas of interest for continuous, long-term monitoring of the human body, while improving user experience.

The authors have highlighted current attempts of mechanically adaptive devices for health care, and the authors forecast key aspects for the future of these conformable biomedical devices and the ways in which these devices will revolutionize how health care is administered or obtained.

The authors conclude this paper with the perspective on the challenges of implementing this technology for practical use, including device packaging, environmental life cycle, data privacy, industry partnership and collaboration.

This study aims to investigate the current and future status of overseas halal food marketing and develops strategies for improving the competitiveness of Korean seafood companies in the global halal food market.

The research uses a case study approach and a semi-structured review of previously published data. Evidence collected from literature reviews, supported by research studies, anecdotal proof, personal reflection and experience is also used. It also considers the perspectives of various stakeholder groups in the global halal food supply chain.

The global halal food market is forecasted to reach US$1.914tn in 2021. At present, Korea holds a small share of this market. To enter the emerging Islamic market, there is a need to develop strategies. This study recommends the following main strategies to improve the competitiveness of Korean seafood companies in the halal food market: reduce mistrust by improving halal authentication and certification standards; understand consumer behavior and develop marketing strategies according to the respective country’s socioeconomic and geographic status; train industry employees and develop competitive halal seafood products; exploit the rising global influence of Hanryu; establish a halal logistics/supply chain and halal industrial parks; and promote digital marketing and tourism. Moreover, the government should also subsidize halal seafood development, as well as provide export and international trade insurances.

As the Muslim population continues to grow, the importance of global halal food marketing also increases. Therefore, strategies for improving the competitiveness of Korean seafood companies in the global halal food market need to be taken into account.

The purpose of this paper is to investigate how the center of pressure (COP) changes depending on the type and wearing method of baby carriers, which is fundamental research for the development of smart baby carriers. In addition, the most comfortable and least burdensome type and method of wearing baby carriers is suggested.

The COP and muscle fatigue were measured depending on the three types and wearing method of baby carriers. And then, the subjective stability, comfort, and fatigue were analyzed.

The results of this study show that horizontal changes to the COP are greater and when baby carriers are worn loosely, subjective comfort is worse. Furthermore, when the shoulder straps are worn loosely, the center of mass moves downwards, lowering the muscle fatigue of the shoulders, but greatly raising the muscle fatigue of the waist and thighs. Comparison of the shapes of baby carriers showed that X-type produced greater muscle fatigue in the shoulders, waist, and thighs, as well as greater subjective fatigue in the shoulders. However, subjective fatigue in the waist decreases when baby carriers without waist support are worn.

It is expected that changes in COP values based on the type and method of wearing baby carriers will be applied as fundamental data for the development of automatic-adjusting smart baby carriers that prevent muscular pain and concentrated pressure.

From the viewpoint of degree of cure, the purpose of this paper is to find how to improve the reliability of flip‐chip packaging modules based on an anisotropically conductive adhesive film (ACF) interconnection process.

The work begins by revealing the correlation of adhesive strength and contact resistance of flip‐chip joint interfaces with the degree of cure of the ACF. The effect of different degrees of curing on the electrical and mechanical properties of some typical ACF‐interconnected joints is studied, and the optimum degree of cure is suggested to achieve highly reliable ACF joints, where the performance variations of the adhesion strength and contact resistance are considered simultaneously. First, the degradation data of the contact resistance of some ACF assemblies, bonded with several degrees of cure, is collected during a standard high‐hydrothermal fatigue test. The resistance distribution is verified using a two‐parameter Weibull model and the distribution parameters are estimated, respectively. After that, a reliability analysis method based on the degradation data of contact resistance is achieved, instead of the traditional failure time analysis, and the reliability index, as well as the mean‐time‐to‐degradation of the ACF joints, as a function of the degree of cure, is deduced, through which the optimum degree of cure value and recommend range are suggested.

Numerical analysis and calculations are performed based on the experiments. Results show that the optimum degree of cure to achieve highly reliable joints is 83 per cent, and the recommend range is from 82 to 85 per cent for the ACF tested (considering a 95 per cent confidence interval).

The paper provides important support for optimizing the curing process for various ACF‐based packaging applications, such as chip‐on‐glass packaging of liquid crystal displays and flip‐chip bonding of radio frequency identification, etc.

This paper explores how gender-related issues are communicated in Korean family-run conglomerates (chaebols) and the roles of women within these businesses. It also addresses to what extent the communication of chaebols about female employment and career development reflects the perception of gender representation in these organisations.

By paying attention to gendered discourse in Korean chaebols, this paper examines what is said and written about gender issues in glottographic statements (texts) and non-glottographic statements (charts and other visuals) of annual reports (ARs) published by five chaebols since 2010. The paper uses a Foucauldian framework to develop the archive of statements made within these ARs.

Although there is an increase in female-employee ratios, ARs show that number of women at the board or senior management level continue to be small. ARs tend to provide numbers related to female employment and retention in their non-glottographic statements, yet these numbers occasionally differ from and frequently are not explained by glottographic statements. The strategies used by chaebols to improve career prospects for their female staff are only vaguely described and rarely evaluated.

This paper looks beyond the existing discourse analysis on “talk and text” by also investigating claims made through graphic and linear/pictorial elements and their interplay with text. This approach opens new understandings of how gendered discourses are constructed and how they (unintentionally) fail to resolve issues and perceptions related to female employment and career development in Korea.