폴리카보네이트에서의 표면개질 조건과 DC-Bias Sputtering 증착에 따른 Cu 밀착성

Abstract

The enhancement of adhesion for Cu film on polycarbonate (PC) surface with the Ar/O2 gas plasma treatment and dc-bias sputtering was studied. The plasma treatment with this reactive mixture changes the chemical property of PC surface into hydrophilic one, which is shown by the variation of contact angle with surface modification. The micro surface roughness that also gives the high adhesive environment is increased by the Ar/O2 gas plasma treatment. These results were observed distinctly from the atomic force microscopy (AFM). The negative substrate dc-bias effect for the Cu adhesion on PC was also investigated. Accelerated Ar+ ions in sheath area of anode bombard the bare surface of PC during initial stage of dc bias sputtering. PC substrate, therefore, has severe roughen and hydrophilic surface due to the physical etching process with more activated functional group. As dc-bias sputtering process proceeds, morphology of Cu film shows better step coverage and dense layer. The results of peel test show the evidence of superiority of bias sputtering for the adhesion between metal Cu and PC.