Palladium-Free Surface Metallization of Polycarbonate Substrate by a Chemical Grafting Technology

• Main Authors: Huei-Fang Huang, 黃慧芳
• Other Authors: 竇維平
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/83730632126903605135

碩士 === 國立中興大學 === 化學工程學系所 === 102 === In recent years, the wireless communication and the applications of cloud technique become more popular. Since the rapid increase in technology, the development of wireless electronic products tend toward light, thin and multi-functional . It has some problems with high wiring density and transmission speed in electronic communication applications. Therefore, the design and fabrication processes of antennas in smart phones have become important for developing wireless communication technology. Currently, laser direct structuring (LDS) technology is the main process for fabricating the antenna of a smart phone. The first step is to mix metal catalysts into a polycarbonate(PC) substrate. The laser ablation can do surface patterning directly. The buried catalysts were thus exposed after laser ablation and could initiate the electroless copper deposition. However, if the exposed catalysts are not uniform or insufficient, the subsequent electroless copper plating will get some problems. To overcome the problems, a variety of surface treatment techniques for metallizing polymer materials have been extensively reported, such as chemical etching treatments, plasma modification…etc. However, they will cause the environmental pollution and they have some equipment limitations. So low-cost and low-pollution chemical grafting technology attracts much attention. In this study, we reported an environmentally friendly and a wet process for the surface metallization of PC. With chemical grafting technology we were able to achieve region-selective metallization. We used Ni, Cu and Ag metals as catalysts to replace Pd for initiating the copper electroless deposition. Finally, the nickel electroplating deposition was used to increase corrosion resistance of antenna. We use X-ray Photoelectron Spectrometer(XPS) and Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy(ATR-FTIR) analysis to observe the changes of chemical bonding and surface functional groups in each steps and speculate a reasonable reaction mechanism. Field Emission-Scanning Electron Microscope(FE-SEM) and Atomic Force Microscopy(AFM) analysis is used to observe the surface morphologies of copper and nickel films. Finally the adhesion between the deposited copper layer and the PC substrate was evaluated by Scotch tape test according to the standard peeling test. The results show that the concentrations and the dielectric constants of the solvents that are used for grafting reaction influence the subsequent catalytic activity of the nickel nano-catalyst. When we use alcohol as the solvent, the plated copper layer has good adhesion and uniformity on the PC substrate. This approach significantly reduce the cost of equipment and processes and accomplishes a Pd-free metallization process.