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1 – 5 of 5Yan Pan, Shuye Zhang, Pengli Zhu and Kyung W. Paik
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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Yan Pan, Taiyu Jin, Xiaohui Peng, Pengli Zhu and Kyung W. Paik
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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Li Peng and Paul Anthony Maria Das
China is experiencing an economic revolution focused on reducing carbon emissions (CEs). Various technological research and development (R&D) frameworks also hasten the growth of…
Abstract
Purpose
China is experiencing an economic revolution focused on reducing carbon emissions (CEs). Various technological research and development (R&D) frameworks also hasten the growth of the digital economy, which then fuels this economic revolution. Nevertheless, several correlation uncertainties in China have been observed between R&D investment and CE reduction with green economic transformation. This phenomenon is attributed to insufficient spatial impact considerations.
Design/methodology/approach
Therefore, this article explored the spatial impacts of the digital economy and R&D expenditures regarding environmental quality using Chinese-related panel data between 2012 and 2021. This study uses the Moran I index to test whether there is a spatial relevance between regional carbon emissions in China and assess the digital economic advancement level using the entropy weight approach. In addition, this article analyzes the direct and indirect impacts following the partial differentiation approach, and then creates an interaction term between the digital economy and R&D investment to assess the moderating effect for examining the influence of investing in R&D on reducing CO2 levels of the digital economy.
Findings
A positive spatial relevance between the digital economy and CEs was then highlighted from the empirical findings. The digital economy expansion also demonstrated higher local CEs while negatively impacting nearby regions. Notably, the digital economy concurrently lowered and increased local CEs in the Eastern and Central zones, respectively. Overall, a larger R&D investment directly impacted the capacity of the digital economy in decreasing the carbon emission intensity (CEI) at a regional level. An accelerated digital economy expansion and lower CEI were recorded in the Eastern zone owing to more significant R&D investments.
Research limitations/implications
China has gradually shifted its focus from reducing CEs to implementing “dual control of carbon” to achieve the “dual carbon” target. Future studies should then involve additional studies concerning the impact mechanism and path selection related to “dual carbon control.”
Practical implications
Investment in R&D plays a key role in reducing carbon emissions from the digital economy. By fostering innovation and technological advances, R&D investment activities can create more energy-efficient digital infrastructures, develop sustainable practices and optimize resource use. In addition, these R&D investments can facilitate the transition to renewable energy sources, enhance data management systems to minimize waste and promote the adoption of green technologies by businesses and consumers. As the digital economy continues to evolve, prioritizing R&D in this area is critical to achieving long-term sustainable development goals and addressing the pressing challenges of climate change. Stakeholders across industries must therefore recognize the importance of investment in research and development as a strategic approach that not only drives economic growth but also ensures environmental stewardship in an increasingly digital world.
Social implications
Investments in research and development not only foster innovation and technological progress, but also promote sustainable practices, which can have significant environmental benefits. In addition, they have the potential to create new jobs, improve public health through better air quality and drive economic growth in a manner consistent with climate goals. As society becomes increasingly dependent on digital solutions, it is critical to harness the power of the digital economy to achieve a more sustainable and inclusive society.
Originality/value
Research development investment is critical to all aspects of regulation. Research on R&D investment can provide direction to local governments in formulating digital economy policies and can be beneficial to local governments in considering regional differences in resource availability. The research and technical innovation strategies in the policies for developing the digital economy can substantially expedite carbon neutrality achievement by 2060.
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Xu Han, Zhonghe Han, Wei Zeng, Peng Li and Jiangbo Qian
The purpose of this paper is to study the condensation flow of wet steam in the last stage of a steam turbine and to obtain the distribution of condensation parameters such as…
Abstract
Purpose
The purpose of this paper is to study the condensation flow of wet steam in the last stage of a steam turbine and to obtain the distribution of condensation parameters such as nucleation rate, Mach number and wetness.
Design/methodology/approach
Because of the sensitivity of the condensation parameter distribution, a double fluid numerical model and a realizable k-ε-kd turbulence model were applied in this study, and the numerical solution for the non-equilibrium condensation flow is provided.
Findings
The simulation results are consistent with the experimental results of the Bakhtar test. The calculation results indicate that the degree of departure from saturation has a significant impact on the wet steam transonic condensation flow. When the inlet steam deviates from the saturation state, shock wave interference and vortex mixing also have a great influence on the distribution of water droplets.
Originality/value
The research results can provide reference for steam turbine wetness losses evaluation and flow passage structure optimization design.
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Jean-Eric Pelet, Bonnie Canziani and Nic Terblanche
Teaching wine tasting online is challenging, even given the curated digital tools of the Wine and Spirit Education Trust, a highly renowned online wine certification system is…
Abstract
Purpose
Teaching wine tasting online is challenging, even given the curated digital tools of the Wine and Spirit Education Trust, a highly renowned online wine certification system is used. This paper aims to initially explore wine experts’ opinions about online wine education and subsequently examine the feasibility of customizing wine appreciation lexicons for Chinese learners.
Design/methodology/approach
A two-study multimethod approach was adopted. Study 1, a two-stage Delphi study, was conducted with 17 wine experts representing a number of countries, using a mix of closed/open-ended questions in an online survey. Data was collected in a market study in Study 2, conducted at agricultural markets in Thailand (pilot test) and China. Dialogues with market sellers were undertaken, evoking mental imagery of wine descriptors to explore the relevance of traditional versus local aromas and flavors in describing wine.
Findings
Findings concentrate on three main areas: general advantages/disadvantages of online wine education, reactions toward asynchronous/synchronous methods of wine tasting and, finally, the feasibility of customizing a wine appreciation lexicon for Chinese learners.
Originality/value
The study presents novel insights into the role of online wine education in China.
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