Plasma pre-treatment of liquid crystal polymer and subsequent metallization by PVD

In this paper surface modification of a liquid crystal polymer (LCP) substrate by oxygen containing plasma pre-treatment and subsequent Cu/Cr deposition by physical vapour deposition (PVD) technique is described. By pre-treatment with oxygen containing plasma more volatile reaction products are generated compared to argon plasma pre-treatment as is shown by the etching rate. The small molecule fragments generated during the pre-treatment process are analyzed by mass spectrometry. After the pre-treatment metal layers with suitable adhesion strength even after 1000 cycles of thermal shock are obtained.