A Vapor-Phase Deposited Polymer Film to Improve theAdhesion of Electroless-Deposited Copper Layer onto Various Kindsof Substrates.

Theadhesion of electrodeposited metal film to polymeric circuitboard substrate is one of the key elements to successful miniaturizationof electronic devices. However, as the size of the circuit patterncontinuously decreases, a novel method is urgently required to increasethe adhesion of the metal film on the substrate, especially on thesmooth surface, which is critical to decrease the minimum featuresize of the metal pattern. In this research, we developed an adhesionpromoter layer by depositing metal chelating poly(4-vinylpyridine)(P4VP) film onto various organic and inorganic substrates via initiatedchemical vapor deposition process (iCVD) to enhance the adhesion betweenthe electroless deposited copper (Cu) layer and the substrate. Thehighest peel strength obtained between the electroless deposited Culayer and P4VP coated substrate was 1.22 kgf/cm. Many advantageouscharacteristics of the adhesion promoter layer, including extremethinness, the improved adhesion strength, conformal coverage, scalabilityof the deposition process, and short process time, will prompt theapplicability of this adhesion promoter layer to industrial scaleproduction. [ABSTRACT FROM AUTHOR]