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Gold coatings are used on connector structures to maintain suitable solderability of the underlying Ni coating layer as well as to prevent surface corrosion during service. However, the likelihood of Au embrittlement in connector solder joints must be minimized by eliminating much of the Au plating from the surfaces using a hot solder dipping or “wicking” procedure prior to final assembly. It was observed that Au removal was most effective by using a double wicking process. Also, a higher soldering temperature improved the efficiency of the Au removal process. A longer soldering time during the wicking process did not appear to offer an appreciable improvement in Au removal. Because the wicking procedure was a manual process, it was found to be operator dependent.

The purpose of this paper is to investigate the effect of typical morphologies of Au-Sn IMCs (intermetallic compounds) at the interfaces of solder and pads on shear properties of laser reflowed micro-solder joints.

Sn-2.0Ag-0.75Cu-3.0Bi (SnAgCuBi) solder balls (120 μm in diameter), pads with 0.1, 0.5, 0.9 or 4.0 μm thickness of Au surface finish, and different laser input energies were utilized to fabricate micro-solder joints with Au-Sn IMCs having different typical morphologies. The joints were performed by a shear test through a DAGE bond test system. Fracture surfaces of the joints were analyzed by scanning electron microscopy and energy-dispersive X-ray spectrometry to identify fracture modes and locations.

Morphologies of Au-Sn IMCs would affect shear properties of the joints remarkably. When needle-like AuSn4 IMCs formed at the interfaces of solder and pads, almost entire surfaces presented the manner of ductile fracture. Moreover, shear forces of this kind of solder joints were higher than those of joints without Au-Sn IMCs or with a nearly continuous/continuous Au-Sn IMCs layer. The reason was that the shear performance of the solder joints with needle-like AuSn4 IMCs was enhanced by an interlocking effect between solder and needle-like AuSn4 IMCs. As a nearly continuous or continuous Au-Sn IMCs layer formed, the fracture surfaces presented more character of brittle than ductile fracture. However, if an Au layer still remained under Au-Sn IMCs, the shear performance of the joints would be enhanced.

The results in this study can be used to optimize microstructures and shear properties of laser reflowed micro-solder joints.

Tape Automated Bonding (TAB) is a modern technology which meets the requirements for micro‐connecting VLSI circuits. The limitations for gang bonding chips with high lead counts and reduced pitches are increased bond forces and induced mechanical stress. Laser soldering is an alternative for such contacts. Because microjoining of surfaces occurs via thermal energy from the laser beam, no mechanical pressure is necessary. Due to the optical properties of the laser beam and the possibility to reduce the laser spot, soldering of small pitches is possible. The results of TAB inner lead bonding with a pulsed Nd:YAG laser are presented. Tapes with three metallisations (Sn, Ni‐Sn and Au) were laser soldered to bumps consisting of gold and gold‐tin. The pull strength of laser soldered TAB‐contacts was optimised by variation of laser power and reliability investigations were performed. The metallurgy of laser soldering is different and more critical to long term reliability than that of gang bonded ILB‐contacts, even if identical tape and bump materials are applied. An accumulation of eutectic 80/20 Au‐Sn solder in the bonded interface results in a strong degradation due to Kirkendall pore formation in the ternary Cu‐Sn‐Au system. The application of a tape with a diffusion barrier of Ni inhibits this effect. But during thermal ageing these contacts show a strong degradation of pull forces which is attributed to the formation of brittle intermetallic compounds of the elements Ni, Sn and Au in the contact area. Laser soldering of Au‐plated tapes to Au‐Sn solder bumps is possible. The contacts show optimal pull forces and a minimal degradation after thermal ageing. This is attributed to the formation of an intermetallic compound with a high stability. The Zeta phase acts as a diffusion barrier between the copper lead and the eutectic Au‐Sn solder.

Surging global natural disasters provide incentive for risk-reducing policies and strategies. In this light, the African Union (AU) engaged a multi-stakeholder policy formulation process between 2002 and 2006, to develop a continent-wide disaster risk reduction (DRR) strategy. Drawing from secondary data, this chapter assesses the process and applies qualitative analysis instruments to critically assess the AU’s disaster policy. Linkages to the 2005 international Hyogo Framework for Action (HFA) are also highlighted. The analysis reveals that Africa’s policy formulation process was belated for over a decade, with respect to international expectations. The formulation process was however largely African owned and led, culminating in a strategy document that reflected African contextual reality at the time, and aligned well with HFA fundamental goals. The applied multi-stakeholder approach enhanced a spirit of participation across levels and was central to the largely successful policy formulation process. However, targeted policy outcomes were not explicit, and poorly formulated indicators marred short- and long-term policy evaluation. Based on these results, we conclude that the African-wide DRR policy formulation processes were belated but participatory, systematic and very successful. Belated policy formulation reflects an initial inertia on the African continent, justified by past negative policy experiences and the desire to succeed. A replication of this policy formulation approach in Africa is recommended, albeit exercising more caution on policy timing, the elaboration of better monitoring and evaluation instruments and criteria. Participation should further embrace modern, risk-free (anti-COVID-19-friendly) information and communication technologies.

This chapter examines the relationship between the gendering of domestic work – its construction as ‘women's work’ – and the treatment within migration regimes of people who do such work. Research on paid domestic workers to date has highlighted that there are many examples of migrant domestic workers being subject to more stringent, limiting or invasive visa regulations than other migrant workers (see, e.g. Constable, 2003; Mundlak & Shamir, 2008; Pratt, 2004; Yeoh & Huang, 1999a, 1999b). Additionally, domestic workers can be excluded from employment protections, such as those that ensure minimum wages or maximum working hours for other groups (Hondagneu-Sotelo, 2001; Mundlak & Shamir, 2008; Pratt, 2004).

In this chapter,¹ I explore topics which unexpectedly emerged in in-depth interviews with Filipino and Eastern European women in Norway, which proved important for the ways in which they experienced their sojourn as au pairs in Oslo. These topics were related to their physical experience of having and being a body, as bodily subjects and as objects for ‘consumption’. To understand au pairs' experiences one must include an analysis both of experiences related to eating practices and experiences related to sexuality, in terms of ‘being a (female) body’ (Bordo, 2003). These two kinds of experiences may be regarded as interrelated and challenge and activate the division between public and private, employer and employee, and involve intimacy and experiences which are interpreted as physical.

Au stud bump bonding technology is an effective means to realize heterogeneous integration of commercial chips in the 2.5D electronic packaging. The purpose of this paper is to study the long-term reliability of the Au stud bump treated by four different high temperature storage times (200°C for 0, 100, 200 and 300 h).

The bonding strength and the fracture behavior are investigated by chip shear test. The experiment is further studied by microstructural characterization approaches such as scanning electron microscope, energy dispersive spectrometer and so on.

It is recognized that there were mainly three typical fracture models during the chip shear test among all the Au stud bump samples treated by high temperature storage. For solder bump before aging, the fracture occurred at the interface between the Cu pad and the Au stud bump. As the aging time increased, the fracture mainly occurred inside the Au stud bump at 200°C for 100 and 200 h. When aging time increased to 300 h, it is found that the fracture transferred to the interface between the Au stud bump and the Al Pad.

In addition, the bonding strength also changed with the high temperature storage time increasing. The bonding strength does not change linearly with the high temperature storage time increasing but decreases first and then increases. The investigation shows that the formation of the intermetallic compounds because of the reaction between the Au and Al atoms plays a key role on the bonding strength and fracture behavior variation.

This paper aims to explore the factors that drive and inhibit national stakeholder organisations’ engagement with an established an umbrella place brand identity (PBI) in the context of country branding, during the PBI implementation stage.

This study adopted a case study approach to examine Australia’s current country brand identity initiative: Australia Unlimited, as an example of PBI. Data were collected through in-depth interviews with senior executives (n = 39) representing 30 Australian national organisation stakeholders across a range of sectors (i.e. government agencies, public and private organisations and industry associations).

The tension between the PBI and the brand identity of the stakeholders’ own organisation was an emergent finding at the heart of potential disengagement. Moreover, stakeholders’ perception of the leadership of the organisation managing the place brand plays a key role in influencing their engagement with PBI.

The findings contribute to place marketing theory by identifying drivers and inhibitors of stakeholders’ engagement that originated from the PBI itself (PBI-centred factors) and from the stakeholder organisations (stakeholder-centred factors).

The findings provide a practical framework for place brand managing organisations to foster stakeholders’ engagement during the implementation stage of a PBI initiative.

Place branding research to date has focussed primarily on resident stakeholders’ engagement in the development of PBI initiatives. This paper contributes to knowledge by proposing a framework that encompasses the drivers and inhibitors of national stakeholder organisations’ engagement with PBI during its implementation phase.

This paper aims to analyze the effect of Au wire size and location of hook during wire pulling test to identify the variation of results obtained.

Two hook locations, namely, location A and location B were used to analyze the effect of hook location. Location A was the same as the hook location required by MIL-STD-883E standard, whereas location B was located near to the second bond. The correlation between new purposed failure modes and MIL-STD-883E standard was developed to reflect on the pull strength with the physical failure.

It was observed that fine pitch Au wire has higher variation and lower process capability of pull strength. Au wire pulled by the hook at location B provides a more representative result compared to that at location A. Fifty per cent or more of Au remnant is required to be considered as a good and reliable Au wedge bond based on the new purposed failure modes.

The evaluation of gold (Au) wedge bond requires a new proper wire pulling test method. This is due to the large variation obtained from the application of current practice of wire pulling test.

The purpose of this study is to address two kinds of printed circuit board (PCB) failures with electrolytic Ni/Au as the surface finish. One was the weak bondability of gold wires to Ni/Au pads and the other was “dull gold” and weak solder wettability, which both caused great loss for the PCB manufacturer.

The failure samples were studied and analyzed in terms of macro- and micro-morphology of the surface finish, its element composition and thickness by various characterization techniques, such as three-dimensional stereo microscope, scanning electron microscope, energy dispersive spectroscopy and X-ray fluorescence spectrum.

Then the causes of the two failures were both found to be the inadequate thickness of gold deposit and other surface finish defects, but these causes played different roles in either failure or the mechanisms differ. Finally, their failure mechanisms were discussed and corresponding countermeasures were put forward for prevention.

This study not only addresses a practical failure problem but also provides some clues to a better and further understanding of the effect of PCB process and management on its quality and reliability in manufacturing practice.

It sheds light on how the thickness and quality of surface finish affects its wire bonding and soldering performances.