Bump and flux

An alternative method of board assembly for leadless components which offers improved yields, reduced network costs, and higher reliability has been developed. The board is initially pretinned by screen printing solder paste and subsequently reflowed. Visual examination of the board allows for solderability checks, including those areas which would be hidden at the time and assembly. Poor solderability problems, solder balls, and solder bridging can be addressed at this time, without as yet being committed to the additional costs associated with assembly. The additional solder volume associated with this process will also provide better long-term storage of the board, as related to solderability. Designs in which selectively more solder is required can now be easily handled by the selective addition of solder through a secondary bumping operation. Design-induced excess and insufficient solder conditions can be eliminated in this way