Adhesion of PVD layers on liquid crystal polymer pretreated by oxygen-containing plasma

The low-pressure plasma pretreatment of liquid crystal polymer (LCP) before PVD metallization is presented. More polar functional groups were present on the substrate surface after oxygen-containing plasma pretreatment. The adhesion strength between PVD Cu/Cr layers and LCP substrates is enhanced with high concentration of oxygen in a gas mixture of oxygen and argon used for plasma pretreatment. Thermal shock test results shows that oxygen plasma pretreatment is well suited to get reliable adherent sputtered metal layers on LCP for applications in electronics.