TSV结构热机械可靠性研究综述

Review on the Thermal Mechanical Reliability of TSV Structures

硅通孔(TSV)结构是三维电路集成和器件封装的关键结构单元。TSV结构是由电镀铜填充的Cu-Si复合结构,该结构具有Cu/Ta/SiO2/Si多层界面,而且界面具有一定工艺粗糙度。TSV结构中,由于Cu和Si的热膨胀系数相差6倍,致使TSV器件热应力水平较高,引发严重的热机械可靠性问题。这些可靠性问题严重影响TSV技术的发展和应用,也制约了基于TSV技术封装产品的市场化进程。针对TSV结构的热机械可靠性问题,综述了国内外研究进展,提出了亟需解决的若干问题:电镀填充及退火工艺过程残余应力测量、TSV界面完整性的量化评价方法、热载荷和电流作用下TSV-Cu的胀出变形计算模型问题等。

Through silicon via（TSV）is a key structural element in three dimensional circuit integration and device packaging.TSV is a composite structure fabricated by process filling electroplated copper into etched silicon via,it consists of Cu/Ta/SiO2/Si multiple interfaces with roughness formed in the via etching process.In the TSV structure,sixfold difference in coefficient of thermal expansion between copper and silicon leads to high thermal stress and related mechanical reliability issues,which block the application and development of the TSV technology,restrict it marketzation.The thermal mechanical reliability aspects of the TSV structure are reviewed,and some research works need to be conducted in the future are suggested.Those works include measurement of residual stress generated in the copper filling and annealing process,assessment of TSV interfacial integrity,computational model of TSV-Cu protrusion under thermal and electric current loads.