小间距线路前处理选择
2020-08-04孟跃东张军
孟跃东 张军



摘 要:在小间距线路制作中,附着力极为关键,如果没有可靠的附着力支撑,小间距线路制作无从谈起。附着力主要决定覆铜板铜面与干膜(又称为感光抗蚀层或抗镀层)的结合效果。附着力形成主要受覆铜板铜面粗化效果限制,不同前处理方式所产生的粗化程度不同。目前,行业内前处理方式可分为两种,即物理处理方式与化学处理方式,最为普遍的為物理处理方式,如磨刷、喷砂、火山灰前处理,也有少数使用化学方式处理,如微蚀、超粗化等。
关键词:小间距线路;前处理;选择
中图分类号:TM216文献标识码:A文章编号:1003-5168(2020)17-0053-03
Selection of Pretreatment for Small Spacing Lines
MENG Yuedong ZHANG Jun
(Henan Haile Electronic Technology Co., Ltd.,Shangqiu Henan 476200)
Abstract: In the production of small-pitch lines, the adhesion is extremely critical, if there is no reliable adhesion support, the production of small-pitch lines cannot be discussed. The adhesion mainly determines the bonding effect of the copper surface of the copper clad laminate and the dry film (also known as photosensitive resist or plating resist). The formation of adhesion is mainly limited by the roughening effect of the copper surface of the copper clad laminate, and the degree of roughening produced by different pretreatment methods is different. At present, the pretreatment methods in the industry can be divided into two types, namely physical processing methods and chemical processing methods, the most common are physical treatment methods, such as brushing, sand blasting, and volcanic ash pretreatment, there are also a few that use chemical treatments, such as micro-etching and super-roughening.
Keywords: small pitch line;pretreatment;selection
当今世界,电子工业飞速发展,这也使电子工业的龙头行业——印制电路业,技术水平不断提高,布线密度越来越高;线条越来越细,最小可达50.8~76.2 μm;多层板内层越来越薄,基材厚度为0.05 mm(不含铜);板的层数越来越多。这些问题都给PCB制造商提出了严峻的挑战,小间距的附着力问题一直是困扰所有PCB厂的难题[1-2],因为它直接影响PCB板的合格率,附着力不好直接导致大批量的报废而使成本上升到一个可怕的程度。
1 概述
正常情况下,贴膜过程中的参数是大致统一的,行业内贴膜压力为4~6 kg/m3,出板温度≥55 ℃,压辘的工作温度为100~120 ℃。如果单一从这些参数入手,效果非常微观,如果配合其他参数,如曝光能量、显影速度,这势必对精细导线的解析效果有所影响。笔者个人认为,做好小间距需要从前处理突破,不论是正片工艺还是负片工艺,唯有提升干膜或油墨与铜面的接触表面积才是真理。……
