摘要
电镀铜填盲孔是高密度互连(HDI)印制线路板(PCB)制造的核心技术之一。随着电镀的进行,镀液中添加剂不断消耗分解,副产物的累积导致镀液填孔能力下降等问题。为延长镀液寿命,在常见的三组分添加剂(即1.5 mg/L聚二硫二丙烷磺酸钠+300 mg/L聚乙二醇8000+50 mg/L整平剂LB)镀液基础上加入自制稳定剂,研究了稳定剂对电镀铜填盲孔时镀液寿命的影响。计时电位分析显示,微量稳定剂的加入基本不会影响镀液中原添加剂的电化学信号,表明微量稳定剂不会影响原添加剂的填孔性能及干扰对原添加剂浓度的分析。循环伏安剥离法分析结果表明,镀液中加入稳定剂后,添加剂在电镀过程中的消耗速率明显降低。哈林槽电镀实验结果表明,稳定剂的加入对填孔效果无明显影响,但无稳定剂的镀液寿命仅250 A·h/L,加入稳定剂后镀液寿命可达500 A·h/L以上。X射线衍射分析表明,新开缸时无稳定剂和含稳定剂镀液的铜镀层均为(200)晶面择优生长,但随着电镀时间的延长,无稳定剂体系铜镀层的择优取向逐渐由(200)晶面向(111)晶面转变,含稳定剂镀液的铜镀层晶型基本不变,镀液性能更加稳定。
Copper electroplating is one of the core technologies for manufacturing of high-density interconnect(HDI)printed circuit board(PCB).The additives in electrolyte are gradually decomposed during electroplating process,leading to the degradation in filling power for the accumulation of by-products.Some home-made stabilizers were added to the traditional electrolyte containing three additives i.e.bis-(3-sulfopropyl)disulfide 1.5 mg/L,polyethylene glycol-8000300 mg/L,and leveling agent LB 50 mg/L to extend its bath life.The effect of stabilizer on the bath life of the electrolyte for blind via filling by copper electroplating was studied.The chronopotentiometric analysis result showed that the addition of a small amount of stabilizer to the electrolyte has little effect on the electrochemical behavior of the original additives,indicating that the via filling power and quantitative analysis of the original additives won’t be affected by the stabilizer.The results of cyclic voltammetric stripping showed that the consumption rates of different additives were decreased greatly after adding a stabilizer to the electrolyte.The result of Hull cell test showed that the microvia filling capability of the electrolyte with and without a stabilizer was almost the same.The bath life of the stabilizer-free electrolyte was only about 250 A·h/L,while that of the stabilizer-containing electrolyte was at least 500 A·h/L.The result of X-ray diffraction showed that both the copper coatings electroplated from the fresh electrolyte with and without a stabilizer show a preferential orientation in Cu(200)plane.With the extending of electrolysis time,the preferential orientation was gradually transformed into Cu(111)plane for the electrolyte without a stabilizer,but basically remained the same for the electrolyte with a stabilizer,indicating that the electrolyte with a stabilizer was much more stable.
作者
廖代辉
詹安达
陈素锐
郑丹霞
孙宇曦
曾庆明
罗继业
LIAO Daihui;ZHAN Anda;CHEN Surui;ZHENG Danxia;SUN Yuxi;ZENG Qingming;LUO Jiye(Guangdong University of Technology,Guangzhou 510006,China;Guangdong Shuocheng Technology Company Limited,Shaoguan 512700,China)
出处
《电镀与涂饰》
CAS
北大核心
2023年第5期33-40,共8页
Electroplating & Finishing
基金
国家自然科学基金(22178071)
广州市科技计划──基础与应用基础研究项目(202102021029)。
关键词
印制线路板
填盲孔
电镀铜
稳定剂
镀液寿命
printed circuit board
blind via filling
copper electroplating
stabilizer
bath life
