PCB中耐高温有机可焊保护剂成膜机理及性能研究OA北大核心CSTPCD

To overcome lead-free high temperature reflow process and obtain satisfactory solder joints on printed circuit board, the key issue is to generate a High-Temperature-Resistant Organic Solderability Preservative (HT-OSP) coating on the surface of copper solder pads. Selecting C14H10Cl2N2 as a coating formation agent, a HT-OSP coating is formed on copper surface. Theoretical calculations combined with comparative experiments, coating formation mechanism of C14H10Cl2N2 molecules reacting with copper atoms generating the HT-OSP coating is investigated. Based on the density functional theory in quantum chemistry, the complexation reactions between C14H10Cl2N2 molecules and cuprous ions are simulated. The typical functional groups in the HT-OSP coating are characterized by infrared spectroscopy. The valences of copper element in the HT-OSP coating are tested by X-ray photoelectron spectroscopy. The influence of copper ions on forming HT-OSP coating is analyzed by designing comparative experiments. The results indicate that the mechanism of generating HT-OSP coating is as follows: C14H10Cl2N2 molecules react with copper atoms generating HT-OSP coating deposition on copper layer surface. Copper ions promote the HT-OSP coating growth by complexation reaction. Moreover, the decomposition temperature of the HT-OSP coating is up to 531℃. The copper layer protected by the HT-OSP coating is not oxidized after 180 days in the atmospheric environment. It is proved that the HT-OSP coating possesses excellent antioxidant and heat resistance.