摘要
对穿透硅通孔(TSV)互连结构的湿-热应力问题进行了有限元分析。首先模拟了在二氧化硅和氢基半硅氧烷(HSQ)低k材料TSV互连结构在回流焊过程中,因热膨胀系数不匹配而引入的热应力,然后预测了HSQ基TSV互连结构在潮湿环境下因湿膨胀系数不同引起的湿应力,以及湿-热环境下的湿-热应力分布。结果表明:湿气会提高TSV结构界面处的等效应力,但湿气对铜线中的应力影响较小。湿-热应力集中主要出现在HSQ材料和与之相邻的硅上。与SiO2基TSV结构相比,HSQ基TSV结构中铜线上的应力集中得到改善,但HSQ和硅界面上的应力集中有所增加。
Thermal-hygroscopic stress of through silicon vias（TSV） was investigated by using the finite element method（FEM）.Firstly,the thermal expansion stresses due to the local thermal expansion mismatch among package materials in TSV with hydrogen silsesquioxane submicron（HSQ） low-k material or silicon dioxide（SiO2） were predicted during the reflow process.Secondly,the hygroscopic stress in TSV with HSQ caused by the differential hygroscopic swelling in humid environment,and thermal-hygroscopic stress distribution under the humid-thermal environment were all analyzed.The numerical results show that equivalent stress in TSV with HSQ is increased by moisture.The moisture absorption has little influence on the equivalent stress in the copper wire.The thermal-hygroscopic stress concentration mainly appears in the interface between HSQ and neighbored Si.Compared with the SiO2-based TSV,the stress concentration of the copper wire in the HSQ-based TSV can be reduced significantly,while larger stresses are found in the interface of the HSQ and Si.
出处
《半导体技术》
CAS
CSCD
北大核心
2012年第11期889-893,共5页
Semiconductor Technology
基金
国家自然科学基金项目(10902048
11162014)
关键词
TSV结构
低K材料
湿-热应力
有限元
铜互连
TSV structure
low-k material
thermal-hygroscopic stress
finite element
copper interconnect
