基于微流原理的通孔互联填充方法可行性研究

项目名称： 基于微流原理的通孔互联填充方法可行性研究

项目编号： No.61504158

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 无线电电子学、电信技术

项目作者： 顾杰斌

作者单位： 中国科学院上海微系统与信息技术研究所

项目金额： 20万元

中文摘要： 硅通孔互连(TSV)是穿透基片的垂直电互连技术，是先进封装中极其重要的技术。通孔互连可以显著减少器件的封装尺寸，降低能耗和提供更好的抗噪性能。在通孔互连制造中，通孔填充是难度最大的一步。铜电镀是目前研究最成熟使用最广泛的通孔填充方法。但这种原子层级的沉淀技术从本质上限制了其填充的速率。使用压力差将液态合金填充入通孔具有速度快成本低的优势，非常适合于几十到几百微米尺寸通孔的填充。但现在的合金填充方法存在着填充质量低，填充过程不清洁以及无法扩展到圆片级等问题。本项目提出并研究利用微流(Micro-fluidic)的微液滴分离技术，实现填入通孔中的微合金柱与合金液面的可控“切割“，从而可以显著的提高合金填充的质量。此外使用的“三明治”结构不仅保证了填充过程的清洁性，而且消除了填充片两面的压力差从而可以使这种方法扩展到圆片级。本项目的研究将极大的提高合金填充作为通孔互联制造的可行性。

中文关键词： 通孔互联；微流；MEMS封装

英文摘要： Through-Silicon Via(TSV) is a vertical feed-through interconnection technology, which is very important for advanced packaging. TSV not only dramatically reduces packaging footprint and energy consumption of devices, but also provides better anti-noise performance. Through-hole filling is the most difficult step in TSV fabrication. Currently Copper-plate is the most studied and used method for through-hole filling. However electro-plating is an atom-level deposition technology, which limits its filling efficiency. Using pressure differential to fill through-hole with liquid alloy is a much faster and cost-efficiency filling process for TSV with size from tens to hundreds of microns. But so far this method suffers from poor filling quality, furthermore the process is limited to die-level and not clean. In this project, we propose that using droplet formation mechanism in micro-fluidic to achieve “controlled-cut” between filled alloy pillars and liquid alloy surface. By this method, the filling quality of alloy can be dramatically improved. In addition, the method employs a “sandwich” structure, which not only make the process much cleaner, but also eliminate pressure differential during filling, thus make it scalable to wafer-level. The research can highly increase the probability of alloy-filling as a TSV fabrication method.

英文关键词： Through-Silicon Via;Micro-fluidic;MEMS Packaging