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The leaching of lead from electronic components in landfills to ground water is harmful to health and to the environment. Increasing concern over the use of lead in electronics manufacturing has led to legislation to restrict its use as a joining material. Consequently, significant recent research efforts have been geared to identification of suitable lead‐free solder pastes. Typically, lead‐free solder pastes contain a very active flux in an effort to improve wetting. These aggressive fluxes have the tendency to explode (or burst) and create flux spatter, causing many process problems with sensitive electronic components. The purpose of this paper is to propose solution procedures to minimize/eliminate these flux spatters, particularly, on gold fingers in memory modules when lead‐free solder pastes are used.

Four no‐clean, lead‐free Sn‐Ag‐Cu (SAC) alloy‐based solder pastes consisting of four different flux systems from three different vendors were evaluated. Two types of reflow profiles (linear and ramp‐soak‐ramp) were also evaluated. Experiments were also conducted to optimise the soak temperature and soak time to determine a broader process window for lead‐free volume production with minimal flux spatter on the contact fingers of memory modules. In order to validate our findings the recommended profile and paste was adopted in production. Additional experiments on a board with a different surface finish were also carried out to validate the recommendations.

Flux spatter can be reduced/eliminated through proper selection of flux chemistry and reflow profile optimisation. The experimental study conducted indicates there is a reduction in the occurrence of flux spatter when a ramp‐soak‐ramp profile is used with lead‐free solder pastes.

Demonstrates that flux spatter can be reduced/eliminated by carefully choosing a soak profile and appropriate flux chemistry.

Economics laboratories have become the primary locations of experimental economics research by the 1990s. They were a result of a decade long development from ad hoc opportune places to dedicated, purpose designed spaces. The distinctive feature of the economics laboratory and its key instrument became networked computers running custom-built software. However, the history of the economics laboratory is not just a history of evolving technology. I argue in this article that it is mainly a history of learning how to build an experimental economics community. Only a functioning community was able to change a physical place to a laboratory space. The distinction between place and space originates in the work of Michael de Certeau and I use it to analyze the evolution of economics laboratories. To this end, I analyze the case of Austin Hoggatt’s Management Science Laboratory at Berkeley in the 1960s as it illustrates the indispensability of creating a community centered on the laboratory. In contrast, the laboratories in Arizona and at Caltech since the 1980s, and in Amsterdam since the 1990s have become successful spaces, because, unlike Hoggatt, they focused equally on community building as on infrastructure and technology. This gave rise to social infrastructure and division of labor in the laboratory space.