摘要 |
<p>A solder clad printed circuit board (100) consists of an electrically insulating substrate that has copper circuit traces (105), portions of which are solderable. A substantially planar layer (120) of a soldering composition is fused to the solderable traces, to form a solder pad that is not domed. The layer is composed of a mass of off-eutectic solder particles (115) that are fused together to form an agglomeration (120) having a porous structure. The solder particles are fused together by heating the off-eutectic solder to a temperature that is between the solidus temperature and the liquidus temperature of the solder. The solder is then cooled below the solidus temperature to solidify it.</p> |