CAJ | 학술논문

多功能、高性能、高可靠及小型化、轻量化是集成电路发展的趋势.以航空航天为代表的高可靠应用中,CBGA和CCGA形式的封装需求在快速增长.CLGA外壳/基板植球或植柱及二次组装之后的使用过程中,常出现焊接不良或其他损伤而导致电路失效,因此需要进行植球植柱焊接返工.在返工过程中,除对焊接外观、焊接层孔隙等进行控制,研究返工过程对植球植柱焊盘镀层的影响也是保证焊接可靠性的重要工作.一次返工后焊盘表面镀金层已不存在,镀镍层也存在被熔蚀等问题,这都对返工工艺及返工后的电路可靠性提出了挑战.文章主要研究返工中镀镍层熔蚀变化趋势以及随返工次数增加焊球/焊柱拉脱强度和剪切强度的变化趋势,并分析返工后电路植球植柱的可靠性.
다공능、고성능、고가고급소형화、경양화시집성전로발전적추세.이항공항천위대표적고가고응용중,CBGA화CCGA형식적봉장수구재쾌속증장.CLGA외각/기판식구혹식주급이차조장지후적사용과정중,상출현한접불량혹기타손상이도치전로실효,인차수요진행식구식주한접반공.재반공과정중,제대한접외관、한접층공극등진행공제,연구반공과정대식구식주한반도층적영향야시보증한접가고성적중요공작.일차반공후한반표면도금층이불존재,도얼층야존재피용식등문제,저도대반공공예급반공후적전로가고성제출료도전.문장주요연구반공중도얼층용식변화추세이급수반공차수증가한구/한주랍탈강도화전절강도적변화추세,병분석반공후전로식구식주적가고성.
Multifunction, small size and weight, high performance and reliability are the development trends for intergrated circuit(IC). In recent years, the application fields (avigation and spaceflight, for example) which require ICs of high reliability, is demanding more and more ICs with CBGA and CCGA package forms. In the process of attaching balls or columns to CLGA shell/substrate and the process of second-assembly of CBGA/CCGA to PCBs, poor soldering is generally induced which possibly cause a failure in use. Rework of balls/columns attachment is therefor necessary. In the process of rework, it is important to research the plated layers of pads as well as soldering appearance, voids of soldering interface etc. After rework of balls/columns attachment, Au-plated layer is of inexistence and Ni-plated layer is partially melted. Both of the problems challenge the rework process and reliability of ICs. The paper is mainly on 3 issues:evolvement trend of Ni-plated layer, evolvement trends of tensile and shear strength of solder balls and columns, analysis of ICs’ reliability after rework.