| dc.description.abstract | Plasma surface modification techniques have been widely used for polymer materials. Surface modification can alter contact angles and functional groups, thereby affecting surface hydrophilicity or hydrophobicity. It can also lead to changes in surface roughness. Furthermore, this study intends to replace the commonly used photo-imageable dielectric material, PI, with a new type of photo-imageable dielectric (PID) material for adhesion testing purposes. This PID has a lower curing temperature (<200℃) and excellent development resolution, which significantly reduce redistribution layers (RDL) production costs. If a strong adhesion behavior between the metal layer and the dielectric material layer can be achieved, potential industrial applications can be explored.
The experiment involves O2 plasma etching, which breaks chemical bonds between atoms on the surface of the PID. This process creates specific functional groups and dangling bonds on the surface of polymer, interacting with metals. On the first step, the changes in chemical composition and surface morphology of the PID after O2 plasma treatment was analyzed using XPS. After surface modification, Ti/Cu thin films were deposited using magnetron sputtering, and the microstructure at the interface of PID/Ti/Cu was observed by SEM. Adhesion property was preliminarily assessed using a cross-cut test, and then cross-cut test was conducted again to re-evaluate the electroplated Cu foil with a thickness of 20 μm.
As a result of this study, oxygen plasma treatment increases the proportion of oxygen-containing functional groups on the surface and enhances surface roughness. In addition, the sputter-deposited film exhibits good adhesion; however, significant differences in adhesion after electroplating were observed due to some difference observed in microstructure. This highlights the influence of the thin-film deposition process.
In conclusion, this study introduces a novel PID and employs oxygen plasma surface treatment. It utilizes material analysis methods to identify factors influencing adhesion, establishing a standard operation procedure to material characterization for future of hybrid bonding technology for heterogeneous integration. | en_US |