COF（Chip on Film）30μm／30μm精细线路的研制.pdfVIP

CO F(C h i p o n F．I m) 30gm／30gm精细线路的研制 何 波 崔 浩 何 为 莫云绮 张宣东 徐景浩 关 健 (珠海元盛电子科技有限公司技术中心 ，广东珠海 51 9060) (电子科技大学应用化学系 ，四川 成都 61()054) 摘 萼 近年来，随着驱动Ic的I／0数量El益增多，芯片I／0端的排列密度也越来越大。为了与间距El益精细的芯 片I／0端相适应，COF基板的线宽／间距已经普遍降到50pm以下，尤其是某些内部引线键合(ILB)端，其线宽／间距已 经减小到1 5pm。由于传统的减成法存在不可避免的侧蚀问题，所以用它来制作如此精细的线路存在一定难度。但是使用 半加成法就能很大程度的抑制侧蚀现象，它更适合于制作非常精细的线路。文章中，介绍以铜箔厚度仅有21．m的溅射型 挠性覆铜板为原材料，采用半加成法制作了最小线宽／间距分别为5 Opm／50pm和30~m／301xm的精细线路基板。在半加成 法的差分蚀刻工艺中，选用硫酸／双氧水蚀刻液来蚀刻去除基材铜，而不是选用常用的盐酸／氯化铜蚀刻液。结果表明， 半加成法具有很好的蚀刻性能，其制作出的线路横截面非常接近矩形。即使基板的线宽／间距由5O ／501xm下降到3O ／ 301xm，线路的横截面依然非常理想，并没有出现向梯形变化的趋势。同时，由于半加成法所需的蚀刻时间非常短，它能 很好的保持线宽，使其与设计尺寸一致。 关键词 COF；精细线路：半加成法 中图分类号：TN41 文献标识码：A 文章编号：1 009-0096(2008)03-0029-04 Production of Fine Lines(301~m／301zm)Applied in COF HE Bo CUI Hao H E Wei MO Yun—qi ZHANG Xuan—dong XU Jing·hao GUAN Jian Abstract In recent years，following the driver IC’s I／O numbers are becoming higher，the density of IC’s bgmps is becoming greater．For suiting these fine pitch bumps，the width／space of COF substrate is smaller than 50gm commonly and especially some width／space of ILB(Inner Line Bonding)has decreased to 1 5pm．Because of the unavoidable side etching，it is difficult to produce these fine lines by conventional subtractive process．The semi— additive process is more suitable for forming finer pattern because it is able to inhibit side etching greatly．In this paper， we have used sputtered FCCL with 2pm copper layer to produce two kinds of fine line substrates which are 50gin／5Ogm and 30gm／3Ogm by semi—additive process．In flash etching of the semi—additive process，we made use of not HC1／CuC12 etchant but H2SO4／H2O2 etchant to etch the base copper．The semi—additive process has a good etching performance and the section of lines formed by it closely resemble rectangles．Even the width／space decreased from 50gm／5Ogm to 3