Reliability Design of Conductive Adhesive Connection in Electronic Packages

电子封装中导电胶连接的可靠性设计

基本信息

批准号：
14550082
负责人：
IKEDA Toru
金额：
$ 1.79万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2003
项目状态：
已结题

项目摘要

Conductive adhesive connection for electronic packaging using anisotropic conductive adhesive film (ACF) and conductive resin are expected to increase year after year due to its easiness for downsizing, manufacturing process under low temperature and including no lead and so on. However, the reliability of adhesive connection is currently lower than that of soldering which has the developed reliability technologies. Developing the evaluation and the design technique for the reliability of adhesively connected electronic packages is very important for the promotion of the adhesive connection technique for electronic packages.Flip chips are often used with other surface mount devices, and are connected with a circuit board using solder joints. During a solder reflow process, a circuit board is heated to the range from 150℃ to 200℃ for the pre-heating, and reached to the peak temperature around, the range from 240℃ to 245℃. During the solder reflow process, some flip chip using adhesive connection are broken or unconnected.In this study, we developed a new design technique for a flip chip using the ACF against the solder reflow sensitivity test. At first, the coefficient of diffusion, and Henry's low coefficient were measured, then the finite element analysis of the moisture absorption was performed to estimate the vapor pressure induced in a flip chip during solder reflow process after moisture absorption in an atmosphere. The stress intensity factors around assumed cracks in a flip chip caused by the estimated vapor pressure were compared with the delamination toughness of an interface between the ACF and the material of a component part (Aluminum terminal, Cu terminal or Si chip). Estimated critical absorption time that causes the delamination during the solder reflow process corresponds well with experimental result.

使用各向异性导电粘合膜（ACF）和导电树脂的电子封装用导电粘合连接由于其易于小型化、低温下的制造工艺以及不含铅等优点，预计将逐年增加。然而，粘合剂的可靠性。目前粘接技术的可靠性低于焊接技术，发展粘接电子封装的可靠性评估和设计技术对于电子封装粘接技术的推广具有重要意义。倒装芯片常被采用。与他人表面贴装器件，并通过焊点与电路板连接。在回流焊过程中，电路板被加热到150℃至200℃范围内进行预热，并达到周围的峰值温度。在240℃到245℃的回流焊过程中，一些使用粘合剂连接的倒装芯片会破裂或未连接。在这项研究中，我们开发了一种使用ACF的倒装芯片设计技术。首先，测量扩散系数和亨利低系数，然后进行吸湿的有限元分析，以估计倒装芯片在吸湿后回流焊过程中产生的蒸气压。将由估计的蒸气压引起的倒装芯片中假定裂纹周围的应力强度因子与 ACF 和部件材料（铝端子、铜端子或硅芯片）之间的界面的分层韧性进行比较。临界吸收回流焊过程中引起分层的时间与实验结果吻合良好。