Knowledge‐based Adhesive Selection for SMT Assemblies

Abstract

The last decade witnessed the increasing use of Surface Mount Technology (SMT) in the assembly of Printed Circuit Boards (PCBs). This fact coupled with increasing component densities, decreasing component pitch, and the need for reliable PCBs has focused attention on the critical components of the manufacturing process including the adhesive used. Components used in PCBs manufactured using SMT, which are to be wave soldered, must be adhesively attached to the board so that they remain in place during the wave soldering process. Utilisation of non‐conducting adhesives for the attachment of electronic components prior to wave soldering has become common throughout the electronics manufacturing industry. The knowledge based adhesive selection adviser described in this paper assists the user (process engineer) in the selection of adhesives for wave soldering of surface mount components. In addition to guiding the user through the adhesive selection process, it provides dispenser related information. This ‘advice’ is derived from the restrictions imposed by the user (including the user's facility temperature), material property requirements, productivity measures and the adhesive dispensing method. The adhesive selection adviser helps the user understand the relationships that need to be considered during adhesive selection. It is applicable to any existing SMT line that uses adhesives within the commercial PCB manufacturing domain.