A new laminate material for high performance PCBs: liquid crystal polymer copper clad films

We have all heard that the primary drivers that are moving the electronics industry can be summarized in three words: faster, smaller, lighter. Many laminate materials have been developed in the history of the electronics industry and each has been designed to provide designers, fabricators and OEMs with interconnects that would satisfy this paradigm. However, as densities increase the demands placed on laminate materials are beginning to approach the limits of some of these materials. To meet manufacturer's needs, new materials must be continually developed to meet the demands of the electronics industry. This paper discusses a newly developed material consisting of a high performance liquid crystal polymer (LCP) laminated to copper foil. LCPs offer a balance of properties unmatched by other engineering or high performance resins. Some of the advantages offered by the LCP copper clad film include: low dielectric constant; very low moisture absorption; laser hole formation; processing similar to standard FR-4 materials; and chemical resistance. Also, this paper discusses the evaluation of multilayer PCB fabricated with liquid crystal polymer copper clad film. The evaluation included peel strength, solder float testing, moisture absorption and moisture and insulation resistance testing. The result of this work was the production of a functional PCMCIA card.