DIMENSIONALLY STABLE SOLDER MASK MATERIAL AND METHOD OF APPLICATION

摘要

The present invention relates to a solder masked semiconductor package or circuit board (24) wherein the solder mask material (25) comprises a porous non-woven material in which the voids of the porous non-woven material contain a mixture of at least one particulate filler and at least one thermoset or thermoplastic resin. Additionally, the invention relates to a method of forming a solder masked semiconductor package, or substrate (24) useful in making a semiconductor package, comprising the steps of laminating a solder mask material to a substrate (22) and forming a solder masked substrate (24), wherein the improvement comprises using a solder mask material (25) which is a non-woven material containing a mixture of at least one particulate filler and at least one thermoset or thermoplastic adhesive resin.