Chemical interaction, adhesion and diffusion properties at the interface of Cu and plasma-treated thiophene-based plasma polymer (ThioPP) films

Chemical interaction, adhesion and diffusion properties at the interface of Cu and plasma-treated thiophene-based plasma polymer (ThioPP) films deposited by plasma-enhanced chemical vapor deposition (PECVD) were studied. Surface characterization of ThioPP films treated by Ar and O plasma using X-ray photoelectron spectroscopy (XPS), contact angle measurements, and 2 atomic force microscopy (AFM) showed the formation of C_O chemical bonds by O plasma treatment and increase in surface 2 roughness resulting in the decrease of contact angle. The chemical interaction between Cu and plasma-treated ThioPP films investigated by XPS showed the formation of Cu–S chemical bonding resulting in the strong adhesion of Cu on ThioPP films. Diffusion properties of CuyThioPP films annealed at 4508C for 1 h were surveyed by current–voltage (I–V) measurement. The slight reduction of Cu diffusion into ThioPP films treated by O plasma compared to that of the samples untreated or treated by 2 Ar plasma is attributed to the formation of new chemical bonding states on the surface of O plasma-treated ThioPP films. 2 2001 Elsevier Science B.V. All rights reserved.