面向三维IC堆栈集成高温单相互连点的快速成形原理研究

项目名称： 面向三维IC堆栈集成高温单相互连点的快速成形原理研究

项目编号： No.U1504507

项目类型： 联合基金项目

立项/批准年度： 2016

项目学科： 机械、仪表工业

项目作者： 田野

作者单位： 河南工业大学

项目金额： 27万元

中文摘要： 三维IC堆栈集成是通过垂直堆栈互连功能芯片组成集成微系统，其中互连键合为核心技术之一，目前重点关注的是固液互扩散键合法。随着互连点尺寸和芯片厚度降低，该方法遇到如下挑战：（1）形成高温互连点，且键合时间短，避免上层芯片键合加热重熔或压溃下层互连点钎料，及热输入过大导致芯片变形。（2）互连点由单相构成，且不发生化合物相变，防止热应力导致相界开裂，及相变形成裂纹。本课题采用Ni/Sn微凸点及Ni纳米化层，通过固液互扩散键合，快速形成高温Ni3Sn4互连点，解决上述挑战。主要研究：（1）Ni纳米化界面Ni3Sn4微观结构演变，探讨界面Ni3Sn4形核长大及粗化机制；（2）Ni纳米化界面Ni3Sn4生长动力学，探讨Ni层纳米化结构对界面Ni3Sn4生长动力影响机制；（3）键合参数优化，探索最佳键合参数，快速制备Ni3Sn4互连点。研究结果将为固液互扩散键合开发一种新方法，促进三维IC堆栈集成发展。

中文关键词： 三维IC集成；互连点；金属间化合物；纳米化；可靠性

英文摘要： Three dimensional IC stacked integration can build up integrated micro-systems by vertically connecting chip together, chip interconnecting is a key technology，now mainly focusing on state-liquid interdiffusion bonding technology. As the joint size and chip thickness reduced, this bonding technology has to face the following challenges: (1) Joints with high temperature, and short bonding time, to avoid remelting and crushing the solder joints of lower level, and chip distortion induced by excess heat input. phase transformation fracture; (2) Joint consisted of single phase, and no phase transformation happening, to prevent crack formation in phase interface caused by thermal stress, and phase transformation fracture. This proposal try to form the Ni3Sn4 joint in a short bonding time, depending on Ni/Sn micro-bump and nano Ni pad layer through state-liquid interdiffusion bonding, which can solve above challenges. The research work as following: (1) Studying on the microstructure evolution of Ni3Sn4 on Ni nano layer, to analyze the Ni3Sn4 grain growth and coarsening mechanism; (2) Studying IMC growth Kinetics on nano layer, to discuss effect of Ni nano layer on Ni3Sn4 growth driving force; (3) Bonding technology optimization, to obtain the optimal bonding parameters, and make Ni3Sn4 joint. The result is to provide a new way for state-liquid interdiffusion bonding, which will promote the development of 3D IC stacked integration.

英文关键词： Three dimensional IC integration; Joint;Intermetallic compound;Nanocrystallization;Reliability