METHOD OF ATTACHING A FLEXIBLE CIRCUIT TO A SUBSTRATE

摘要

A circuit board assembly which includes a flexible printed circuit bonded to a substrate by an adhesive that is curable upon exposure to actinic radiation of a preselected wavelength is provided. The flexible circuit includes a dielectric layer made from a material that is transmissive to actinic radiation of a preselected wavelength and a conductive layer disposed on a surface of the dielectric layer. The conductive layer has an opening therethrough to allow passage of the actinic radiation through the flexible circuit. Preferably, the opening is in the region of the conductive layer that lacks metal tracings. The substrate of the assembly includes a top surface defining a mating region and a channel and a side surface defining a port that is in communication with the channel. The channel of the substrate is aligned and coincident with the opening of the conductive layer. The adhesive is disposed within the channel. The mating region of the substrate is in direct contact with the flexible printed circuit such that there is little to no adhesive between the mating regions of the top surface of the substrate and the mating surface of the flexible circuit. Thus, the circuit board assemblies of the present invention may be thinner than their prior art counterparts that have an adhesive between the substrate and the flexible printed circuit. The present invention also relates to the flexible printed circuits of the circuit board assembly.