Tin per kg over years: In 2006, about half of all tin produced was used in solder. The rest was divided between tin plating, tin chemicals, brass and bronze alloys, and niche uses. Tin has long been used in alloys with lead as solder, in amounts 5 to 70% w/w. Tin with lead forms a eutectic mixture at the weight proportion of 61.9% tin and 38.1% lead (the atomic proportion: 73.9% tin and 26.1% lead), with melting temperature of 183 °C (361.4 °F) . Such solders are primarily used for joining pipes or electric circuits. Since the European Union Waste Electrical
Thermal copper pillar bump both having copper pillars and solder connections. The primary difference between the two is the introduction of either a P- or N-type thermoelectric layer between two solder layers. The solders used with CPBs and thermal bumps can be any one of a number of commonly used solders including, but not limited to, Sn, SnPb eutectic, SnAg or AuSn. Figure 5 shows a device equipped with a thermal bump. The thermal flow is shown by the arrows labeled “heat.” Metal traces, which can be several micrometres high, can be stacked or interdigitated to provide highly conductive pathways for collecting heat from