Investigation of Bondply Leakage Disposition at Inner PCB Layers During Process of Thermal-Pressure Bonding

The results of the thermal pressure bonding of printed circuit board materials are presented. Results have shown a disposition of prepreg leakage at inner printed circuit boards layers. To estimate how the placement of cavities affects the amount of leaked prepreg a pattern of several milled squares was formed at a top layer of the circuit board. This estimation may help designers of certain technology-based boards (cavity milled) to place PCB cavities at optimal positions and provide data about critical bounds, at which positioning of circuit board cavities may be rejectable or at least less desirable.