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The purpose of this paper is to evaluate the influence of assembly parameters on lead-free solder joints reliability in Package-on-Package (PoP) Technology and demonstrate factors important for this issue.

Two types of soldering materials and three different assembly procedures were used for assembly of PoP system. The reliability properties of assembled PoP systems were investigated using accelerated aging and periodic resistance measurements of daisy-chain solder joints systems. The purpose of such approach was to determine which soldering material (flux or solder paste) as well as which assembly process parameter (dipping depth of upper component in soldering material), would provide better reliability properties of the solder joints in the PoP system.

It was stated that both selected flux and solder paste dedicated to assembly of PoP systems can be utilized in soldering of PoP applications. More reliable PoP systems applications require larger attention regarding materials selection and assembly parameters. It is recommended 50 per cent dipping depth of ball’s height into soldering material during upper PoP component assembly for more reliable applications. For less demanding PoP systems, the process window from 30 up to 70 per cent is acceptable. All observed failures after thermal shocks occurred in upper PoP components.

This paper explains how materials and assembly parameters have influence on lead-free solder joints reliability in PoP systems. Especially, influence of process window for dipping procedure of upper components balls into soldering material was presented.

The purpose of this paper is to evaluate the influence of solder powders sizes applied in soldering materials used for Package-on-Package (PoP) system manufacture as well as other factors on reliability and mechanical strength of created solder joints in three-dimensional (3D) PoP structures.

The design of experiments based on the Genichi Taguchi method were used in the investigation. The main factors covered different printed circuit board (PCB) coatings, soldering materials with solder powders sizes from Types 3 to 7 and soldering profiles. The reliability of 3D PoP structures was determined by measurements of resistance of daisy-chain solder joints systems during thermal shocks (TS) cycles. The mechanical strength of solder joints in 3D PoP structures was determined by measurements of a shear force of “Top” layer of 3D structures at T0 and after 1,500 TS. The ANOVA was used for results assessment.

The size of solder powders applied in soldering materials had small (10 per cent) influence on mechanical strength of solder joints in 3D PoP structures. Small size of solder powder had positive effect on solder joints reliability in 3D PoP structures. Especially important was the selection of solder paste for “Bottom” layer of 3D PoP system (influence 17 per cent). Incorrect soldering profile (influence 46 per cent) or wrong selected PCB coating (influence 35 per cent) can very easily reduce the positive impact of soldering materials on solder joints reliability. It was stated that as low as possible soldering profile and organic solderability preservative (OSP) coating in the case of single-sided PCB are the best for 3D PoP structures due to their reliability.

This paper explains how different sizes of solder powders used nowadays in solder pastes influence on reliability and mechanical strength of the solder joints in 3D PoP structures. The contribution, in numerical values, of soldering materials, soldering profile and PCB coating on 3D PoP structures solder joints reliability as well as recommendations improving reliability of 3D PoP structures solder joints were presented.

The purpose of this paper is to present challenges met during package-on-package (PoP) technology implementation in real surface-mount technology assembly processes.

The properties and behavior of different combinations of soldering materials, PoP components and soldering profiles were investigated, both in the laboratory and during production trials. The purpose of such an approach was identification of existing problems and challenges in lead-free PoP systems assembly as well as checking which soldering material designed to PoP is more suitable for this technology.

Technological trials are needed to select adequate soldering materials for PoP systems assembly, as laboratory tests of materials alone were not sufficient. The challenges of PoP technology were associated with the equipment utilized, the soldering materials, operational parameters and the soldering profile used for assembly. The localization of defects in PoP systems is very difficult and, in many cases, destructive methods have to be used on solder joints for the assessment and confirmation of failures.

This paper shows main materials and soldering challenges in lead-free PoP technology. In particular, the problem related with selection of soldering materials and soldering profiles for PoP was presented. Moreover, the issues that have to be taken into consideration during the planning of a PoP system assembly procedure are presented.

The main aim of this paper is to explore the influence mechanisms of perceived organizational politics (POP) on employee performance (EP). Drawing on the job demands-resources theory (JD-R), this paper investigates opportunistic silence (OS) as a mediating factor and job level as a moderating effect in the POP-OS-performance relationship.

This study’s data were collected from 203 employees working in Indian high-power distance organizations (HPDOs), such as the military, police and security forces. Mediation and moderation analysis were conducted using PLS-SEM, and the moderated mediation index was calculated using Hayes PROCESS Macro.

The results indicate that OS fully mediates the POP-performance relationship – specifically, POP as a job demand activates OS, which acts as an energy/resource depleting mechanism and further deteriorates task performance. Interestingly, the overall negative influence of POP and OS on EP was stronger for employees at lower job levels than those at senior job levels.

This paper offers a unique set of findings that enrich the understanding of factors responsible for employees’ performance in the highly political environments of HPDOs. By using the lens of JD-R theory, this paper draws attention towards the tendency of employees to indulge in self-serving behaviours like OS in politically charged contexts which is detrimental to their performance and may also undermine overall organization’s productivity. Furthermore, this paper also highlights the conditional effects exerted by job level in the unique nexus of POP, OS and EP.

Adopting an affective events perspective, our study investigates the relationship between perceived organizational politics (POP) and employee voice by exploring the mediating role of affect and the moderating role of supervisor political support.

The hypothesized model was tested with three-wave data collected from 393 full-time employees.

Results indicate that POP indirectly impacts employee voice through influencing positive and negative affect, and that supervisor political support moderates these indirect effects by moderating the relationship between POP and affective states.

Survey data can hardly test the causal relationship. Effect of employees' POP could be further examined in the lens subjective positive experiences. Organizational politics might have positive meanings.

Our findings show that POP brings employees negative feelings and reduces their voice behaviors while supervisor political support can mitigate this inhibiting effect. Therefore, managers should learn how to use political behavior more reasonably in highly political work environment.

By highlighting the possibility that employees can be beneficiaries having a vested interest in political environment and investigating the unexplored affective explanatory mechanisms underlying the POP–voice relationship, this study provides new directions for future research on POP and employee voice.

In this paper I bring together interaction, media, deviance, self, and identity to make sense of how young Singaporeans consume Korean popular (hereafter, K-pop) music and culture. My overarching goal is to highlight that being a music fan is not a straightforward or even easy experience. Rather, the self as music fan is continually developing within a complex variety of social processes, from the circulation of global, mass media representations to inter- and intra-personal interactions. I present data collected from a study on K-pop music consumption in Singapore, a small island-nation in Southeast Asia with an insatiable thirst for foreign culture. The data show how a group of Singaporean K-pop fans were regularly bombarded with largely negative messages about what it means to be K-pop music fans, and how these meanings affected their own negotiations as fans. K-pop fandom provided a sense of shared identity and status within popular youth culture, yet their experiences were often soured by negative media portrayals of deviant fans, whose behaviors risked stigmatizing the K-pop social identity. This paper thus deals with some of the problems for self that being a music fans entails.

This study explores the influence of heritage brand extension on consumer purchase intention and analyses the effects of pop culture involvement. The extension of heritage brands is becoming increasingly difficult because such an extension needs to be consistent with the unique characteristics of brands and resonate with consumers. However, few scholars discuss the influence of consumers' level of pop culture involvement on brand extension and purchasing behaviour.

Taking time-honoured brands as an example, this study established a conceptual model based on a comprehensive review of the literature, and then tested the model using a sample of 255 respondents who were familiar with one of the selected Chinese time-honoured brands. Structural equation modelling was used to analyse the relationships amongst brand extension fit, pop culture involvement, perceived value and purchase intention.

Time-honoured brand extension fit has a positive impact on consumer purchase intention, and this path is significantly influenced by the mediation mechanisms of perceived value. Situational pop culture involvement can significantly strengthen the relationship between time-honoured brand extension fit and perceived value, whereas enduring pop culture involvement does not.

The results clarify and expand on the different roles of cultural involvement in time-honoured brands and broaden research on the influence of cultural involvement in this regard. This study has significant theoretical value for the inheritance and revival of heritage brands and provides a reference for the practice of time-honoured brands.