Leveling Agents For Printed Circuit Boards In Acid Copper Plating

The purpose of the topic in this thesis is to study several new leveling agent used in acid electroplating copper.Under the free radical iniator of azobisisobutyonitrile(AIBN),poly(N-vinyl-N'-butylimidazoliniumbromize-co-butylacrylate)(QVI-BA),poly(N-vinyl-N'-butylimidazoliniumbromize-co-N-vinylketopyrrolidine)(QVI-N VP)and poly(N-vinylimidazole-co-N-vinylketopyrrolidine) (VI-NVP) were synthesized from N-vinylimidazole,halogenide, butylacrylate(BA) and N-vinylketopyrrolidine(NVP). Compounds of N-vinylimidazole with polyether chain were synthesized from N-vinylimidazole and 1,4-butanediol diglycidyl ethe(BDE).The structures of products were characterizde by IR spectroscopy,1H-NMR spectroscopy,etc.The solubility of products were tested in acid water.The dosage range and the best daosage level of brightener, wetting agents and leveling agents in the complex additive system were confirmde by the quality and area of coating in cathode slice throug doing experiment of Hull cell.The results showed that the brightening, leveling and fine coatings can be got by adding the five kinds of complex additive systems to acid bath.The surface morphology of the coating characterized by doing electroplating experiment.The optical microscope(200times) and SEM of coatings indicated that the five kinds of additive systems had good coverage power and the complex additive system of VI-BDE(1:1) had best refining capacity.The five kinds of synthetic products could be studied as acid electroplating copper according to the cathodic polarization curves.The results showed that all of QVI-BA, QVI-NVP, VI-NVP,the polyether products of VI-BDE(1:1)and VI-BDE(1:0.5) can promote the copper ion into polarization in PCB acid electroplating copper bath obviously. The results of AC impedance test to the five kinds of complex additive systems showed that all of them have chemical reaction impedance on copper clectrodeposition. Which have obvious chemical reaction impedance on copper clectrodeposition were QVI-BA, VI-BDE (1:1) and VI-BDE (1:0.5) complex additive systems.Finally, the five kinds of synthetic products were be as leveling agents used in ascid electroplating copper.The bath of the five kinds of additive system which were QVI-BA compound additive system, QVI-NVP compound additive system,VI-NVP compound additive system,the polyether products of VI-BDE(1:1) and VI-BDE(1:0.5) compound additive system was tested on covering power and througing power.The results indicated that covering power of the five kinds of additive system was up to 100%.Throughing power of additive system of VI-BDE (1:1) was best and better than the brightener YL-623A which has good performance of leveling.Comparation and analysis were done among results of refining power and testing bath of the six kinds of composite additive system which were QVI-BA compound additive system, QVI-NVP compound additive system, VI-NVP compound additive system,the polyether products of VI-BDE(1:1) compound additive system, the polyether products of VI-BDE(1:0.5) compound additive system and the system of YL-623A.The results showde that the additive system composed from SPS,PEG-6000,polyether compounds of VI-BDE (1:1) was one kind of additive having good property usde in PCB ascid electroplating copper.