Modeling and Control of Wafer Scale Yield Improvement in Chemical Mechanical Planarization (CMP)

本计画的目的是借由在化学机械平坦化制程中，提高晶圆级材料移除速率的均匀性，以提升IC制造中的晶圆良率。减少和消除边缘排斥是这个项目特别感兴趣。将采用基于综合模型的控制方法。将开发一个将材料去除速率与晶片-焊盘界面压力和晶片背面负载分布相关联的分析模型。模型预测将首先在静态条件下和材料去除率数据进行验证。基于上述模型的主动控制算法将被开发。特别地，将追求曲率控制算法。这将首先在软件中实现，然后在hardware.It预计，该项目将开发理解相关的纳米级的细微差别的化学机械平面化过程中的宏观尺度的设计考虑。这将促进工艺参数的有效优化和控制，目前主要通过反复试验来完成。通过产学合作，拟议的项目将通过让研究生和本科生接触控制纳米级材料去除过程的新方法来帮助人力资源开发。目前，3-5 mm晶圆边缘排除用于在晶圆上收获“可用”芯片，这影响了300 mm晶圆上约20%的芯片。如果成功，该项目将直接影响和提高这些过程的产量。

The objective of this project is to enhance wafer yield in IC manufacturing by enhancing the wafer scale uniformity in material removal rate during a chemical mechanical planarization process. Reduction and elimination of edge exclusion is of particular interest to this project. An integrated model based control approach will be pursued. An analytical model relating the material removal rate to the wafer - pad interface pressure and wafer backside loading profile will be developed. The model predictions will be verified first under static conditions and from material removal rate data. An active control algorithm based on the above model will be developed. In particular, the curvature control algorithm will be pursued. This will be implemented first in software, and then in hardware.It is anticipated that this project will develop understanding to relate nano-scale nuances of the chemical mechanical planarization process to macro-scale design considerations. This will facilitate efficient optimization and control of process parameters, which is currently done mostly through trial and error iterations. Through Industry-University collaboration, the proposed project will aid in human resource development by exposing graduate and undergraduate students to novel methods of controlling nano-scale material removal processes. Currently a 3-5 mm wafer edge exclusion is used to harvest "usable" chips on wafers, and this affects about 20 percent of the chips on a 300 mm wafer. If successful, this project will directly impact and enhance the yield of such processes.