Allan R. Knoll

Oxygen plasma modification of polyimide webs: effect of ion bombardment on metal adhesion

Webs of Kapton 200-H and Upilex-S polyimide films were treated using oxygen plasma prior to sequential sputter deposition of chromium and copper in a roll metallization system. Two plasma system configurations were employed for treatment. In one configuration, the sample traveled downstream from a microwave plasma; in the other, the web moved through a DC-generated glow discharge. For the DC-glow treatment, the potential difference between the plasma and the web, Φf, and relative ion densities, n+, were measured at various values of chamber pressure and DC power using a Langmuir probe. Although samples treated downstream from the microwave plasma were not subjected to bombardment by energetic ions, Φf for the DC-glow operating conditions was between 5 and 13 eV. For both films, advancing DI water contact angles of less than 20° were achieved using both modes of treatment. Contact angles for untreated films were greater than 60°. However, 90° peel tests yielded values of 15 to 20 g/mm for microwave plasma ...