PCB通孔高电流密度电镀铜用加速剂的研究

Study on accelerators for copper electroplating of through-hole on PCB at high current density

在由75 g/L硫酸铜、200 g/L浓硫酸和65 mg/L盐酸组成的基础镀液中添加1 mg/L聚乙二醇(PEG10000)作为抑制剂,1 mg/L2-巯基-5-甲基-1,3,4-噻二唑(MMTD)作为整平剂,以及1mg/L聚二硫二丙烷磺酸钠(SPS)、噻唑啉基二硫代丙烷磺酸钠(SH110)、3-(苯并噻唑-2-巯基)丙烷磺酸钠(ZPS)、异硫脲丙基硫酸钠(UPS)、聚二硫二乙烷磺酸钠(SES)或聚二硫二己烷磺酸钠(SHS)作为加速剂。先通过计时电位法初步筛选得到合适的加速剂,再通过印制电路板(PCB)通孔电镀实验确定最佳加速剂。结果表明,采用1 mg/L UPS作为加速剂时,镀液在3 A/dm^(2)电流密度下的深镀能力达86.9%,所得铜镀层表面致密平整,抗热冲击性能良好。

The electrolyte comprising CuSO_(4)ꞏ5H_(2)O 75 g/L,concentrated sulfuric acid 200 g/L,and concentrated hydrochloric acid 65 mg/L for copper electroplating of through-hole on printed circuit board(PCB)was added with 1 mg/L polyethylene glycol(PEG10000)as inhibitor,1 mg/L 2-mercapto-5-methyl-1,3,4-thiadiazole(MMTD)as leveler,and 1 mg/L bis-(sodium sulfopropyl)-disulfide(SPS),sodium thiazolinyl dithiopropane sulfonate(SH110),sodium 3-(benzothiazol-2-ylthio)-1-propanesulfonate(ZPS),sodium 3-(amidinothio)-1-propanesulfonate(UPS),bis-(sodium sulfoethyl)-disulfide(SES),or bis-(sodium sulfohexyl)-disulfide(SHS)as accelerator.Suitable accelerators were selected by chronopotentiometry firstly,and then the optimal one was determined by copper electroplating experiment of through-hole on PCB.The electrolyte containing 1 mg/L UPS as accelerator had a throwing power of 86.9%at a current density of 3 A/dm^(2),and the Cu coating electrodeposited therefrom was compact and smooth with good thermal shock resistance.