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The aim of the paper is to study the feasibility of direct ultrasonic bonding between contact pad arrays on flexible printed circuit boards (FPCB) and rigid printed circuit boards (RPCB) at ambient temperature.

Metallization layers on the RPCB comprised Sn on Cu while the pads on the FPCB consisted of Au/Ni/Cu. Prepared RPCB and FPCB were bonded by ultrasound at ambient temperature using an ultrasonic frequency of 20 kHz, a power of 1,400 W, and 0.62 MPa of bonding pressure. The bonded samples were cross‐sectioned and the joints and microstructures were observed by Field Emission Scanning Electron Microscopy (FE‐SEM) and Energy Dispersive Spectroscopy (EDS). The soundness of the joints was evaluated by pull testing.

Robust bonding between FPCB and RPCB was obtained by bonding for 1.0 and 1.5 s. This result has confirmed that direct room temperature ultrasonic bonding of Au and Sn is feasible. At a longer bonding time of 3.0 s, cracks and voids were found in the joints due to excessive ultrasonic energy. The IMC (intermetallic compound) between the Sn layer and pads of the RPCB was confirmed as Cu₆Sn₅. On the FPCB side, Cu₆Sn₅ and Ni₃Sn₄ were formed by contact with the facing Sn coating, and mechanically alloyed Cu_0.81Ni_0.19 was found within the pads. Meanwhile, the strength of bonded joints between FPCB and RPCB increased with bonding time up to 1.5 s and the maximum value reached 12.48 N. At 3.0 s bonding time, the strength decreased drastically, and showed 5.75 N. Footprints from the fracture surfaces showed that bonding started from the edges of the metal pads, and extended to the pad centers as ultrasonic bonding time was increased.

Direct ultrasonic bonding with transverse vibration at ambient temperature between the surface layers of the pads of FPCB and RPCB has been confirmed to be feasible.

This paper seeks to decrease the soldering temperature of capacitors using Sn‐Bi plated Sn‐3.5 wt%Ag solder.

Sn‐Bi layers were electroplated on Sn‐3.5 wt%Ag solder. As soldering examples, type 1608 capacitors electroplated with Sn, and printed circuit boards (PCBs) with a surface coating of electroless‐plated Ni/Au, were selected. Sn‐3.5Ag foil coupons plated with Sn‐95.7 wt%Bi were inserted as solder between the capacitors and the lands on the PCBs. The samples were reflowed at 220°C, which is below the normal reflow temperatures of around 240 ∼ 250°C used with Pb‐free solders. During heating, Bi in the plated layer diffuses into the Sn‐3.5Ag core solder resulting in a transient decrease in soldering temperature based on the concept of transient liquid phase bonding.

The joints made with the Sn‐95.7%Bi plated Sn‐3.5Ag solder at 220°C showed good appearance, and evidence of significant Bi segregation was absent in the microstructure. The shear strengths of the capacitor joints bonded with Sn‐95.7%Bi plated Sn‐3.5%Ag solder were approximately 5,000‐6,000 gf. After 1,000 thermal cycles between −40 and +125°C, the shear strengths of the joints decreased approximately 5‐10 percent from the strengths in the as‐reflowed state for all plated solders. This confirmed that the soldered joints were stable and not significantly degraded by thermal cycles.

Reduced temperature soldering using Sn‐Bi plated Sn‐3.5%Ag solder was applied to attach capacitors to PCBs. In a production application, the foil coupons could be replaced by pre‐solder on the PCB pads.

Creativity and innovation have been buzzwords of managerial discourse over the last few decades as they contribute to the long-term survival and competitiveness of firms. Given the non-linear, causally ambiguous, and intangible nature of all innovation-related phenomena, management scholars have been trying to uncover factors that contribute to creativity and innovation from multiple lenses ranging from organizational behavior at the micro-level to strategic management at the macro-level. Along with important and insightful developments in these research streams that evolved independently from one another, human resource management (HRM) research – especially from a strategic perspective – has only recently started to contribute to a better understanding of both creativity and innovation. The goal of this chapter is to review the contributions of strategic HRM research to an improved understanding of creativity at the individual-level and innovation at the firm-level. In organizing this review, the authors rely on the open innovation funnel as a metaphor to review research on both HRM practices and HRM systems that contribute to creativity and innovation. In the last section, the authors focus on more recent developments in HRM research that focus on ambidexterity – as a way for HRM to simultaneously facilitate exploration and exploitation. This chapter concludes with a discussion of future research directions.

There is an abundance of empirical evidence on the positive effects of employment – and the detrimental effects of unemployment – on individuals’ psychological and physical health and well-being. In this chapter, the authors explore whether and how self-employment or entrepreneurship could be a solution for individuals’ (re)entry to the job market and which (psychological) variables enhance the likelihood of entrepreneurial success. Specifically, the authors first focus on unemployment and its detrimental effects for health and wellbeing, and outline the existing interventions aimed at assisting reemployment and combating the negative consequences of unemployment for individuals’ well-being. Then, the authors will explore entrepreneurship as a potential solution to unemployment and explore the psychological variables that enhance the likelihood of entrepreneurial success. One of the variables the authors highlight as particularly relevant for self-employment is the second-order construct of Psychological Capital (PsyCap; Luthans, Avolio, Avey, & Norman, 2007), as well as its individual components – hope, optimism, efficacy, and resilience. PsyCap is a malleable construct that can be successfully trained, and PsyCap interventions are inherently strength-based and have positive effects on employees’ and entrepreneurs’ performance and wellbeing. Therefore, the authors end the chapter by suggesting that a PsyCap component in existing education and training programs for entrepreneurship is likely to not only increase entrepreneurial intentions and success, but also increases participants’ well-being, self-esteem, and the general confidence they can pick up the reigns and take back control over their (professional) lives.

The purpose of this paper is to determine: how much the residual curvature could be formed in sintered nano‐silver assembly when it is cooled to room temperature from the sintering temperature (normally 275°C); how the cyclic temperature load affects the residual curvature or stresses in sintered joint. Then the stress level and the reliability of sintered nano‐silver for high‐temperature applications can be understood.

5 mm * 2.5 mm silicon chip was bonded with 96 per cent Al₂O₃ substrate by sintering nanosilver paste. An optical system was developed to measure the curvature of the sintered assemblies. Reliability of the sintered assemblies was evaluated by temperature cycling of −40∼125°C. Finite element analysis was employed to simulate the behavior of the joint subjected to the temperature cycling from −40°C to 125°C by ANSYS. SEM images were taken to investigate the impact of temperature cycling on the reliability of sintered silver attachment.

This residual bending at room temperature was found concave towards the substrate (alumina) side. Also, with the bondline thickness increasing, the residual curvature decreases obviously. The severity of the residual bending in all the structures was mitigated to some extent with increasing number of cycles. There is no crack in the joint with the thickness of 25 μm. The drop of the residual curvature of the samples with bondline of 25 μm is caused mainly by stress relaxation in sintered silver before 300 cycles. Sample with thicker bondline is more susceptible to thermal cycling for the structure bonded with nanosilver than that with thinner bondline. The poor quality of bonding is due to the thicker sintered joint, which means that sintered nanosilver is not suitable for die‐attachment requiring thick bondline.

The paper describes: how a precise optical system was developed to measure the residual curvature of the sintered assemblies; how the evolution of the residual curvature of the sintered assembly with the temperature cycling was obtained by both experiment and simulation; and how microstructures of the sintered silver joint were analyzed for as‐sintered assembly and the sintered assembly after temperature cycling.

High-involvement work processes (HIWPs) are associated with high levels of employee influence over the work process, such as high levels of control over how to handle individual job tasks or a high level of involvement at team or workplace level in designing work procedures. When implementations of HIWPs are accompanied by companion investments in human capital – for example, in better information and training, higher pay and stronger employee voice – it is appropriate to talk not only of HIWPs but of “high-involvement work systems” (HIWSs). This chapter reviews the theory and practice of HIWPs and HIWSs. Across a range of academic perspectives and societies, it has regularly been argued that steps to enhance employee involvement in decision-making create better opportunities to perform, better utilization of skill and human potential, and better employee motivation, leading, in turn, to various improvements in organizational and employee outcomes.

However, there are also costs to increased employee involvement and the authors review the important economic and sociopolitical contingencies that help to explain the incidence or distribution of HIWPs and HIWSs. The authors also review the research on the outcomes of higher employee involvement for firms and workers, discuss the quality of the research methods used, and consider the tensions with which the model is associated. This chapter concludes with an outline of the research agenda, envisaging an ongoing role for both quantitative and qualitative studies. Without ignoring the difficulties involved, the authors argue, from the societal perspective, that the high-involvement pathway should be considered one of the most important vectors available to improve the quality of work and employee well-being.