摘要
圆片级封装再布线层结构改变焊盘布局从而提升器件I/O密度和集成度,在移动电子产品中得到广泛应用,其热机械可靠性备受关注。按照JEDEC标准对含RDL结构的WLP器件进行了温度循环试验,研究了WLP器件结构对可靠性的影响。结果表明,随样品节距减小,器件的可靠性降低;相同节距时,焊球直径越小可靠性越低。通过失效分析发现了3种与互连结构有关的失效模式,其中一种与RDL结构直接相关,且对大节距的WLP器件可靠性产生了较大影响。结合有限元模拟,对再布线结构圆片级封装的失效机理进行了深入地分析。
Wafer level packaging （WLP） with redistribution layer （RDL） can increase the I/O density and integration of the package by redistributing pad locations. Wafer level packages are widely applied in mobile electronic devices, and their thermo-mechanical reliability has drawn much attention. WLP devices with RDL were experienced through temperature cycling test according to the JEDEC standard. The effect of the device structure on the reliability of the WLP with RDL structure was studied. The reliability of the WLP decreases along with the decrease in the pitch size. WLP with smaller solder ball size shows the worse reliability when the pitch size is fixed. Three failure modes concerning the interconnection were found through failure analysis. Among these three, one mode arisen ditectly from the RDL structure was observed, which had a large influence on the reliability of WLP with large pitch size. The failure mechanism of the WLP devices with RDL structure was discussed in combination with the finite element analysis results.
出处
《半导体技术》
CAS
CSCD
北大核心
2013年第9期709-714,共6页
Semiconductor Technology
基金
国家科技重大专项资助(2011ZX02602)
