Heterogeneous Wireless Sensing and Modeling of Chemical-Mechanical Interactions in Chemical Mechanical Planarization Process for Microelectronic Applications

本研究项目的目的是解决半导体芯片精加工中化学机械刨平/抛光（CMP）过程的预测建模和实时监控中的以下问题：硅片-衬垫界面的化学和机械现象的相互作用，机器振动、力、温度分布和声发射信号的影响，以及非线性随机过程-机器相互作用的建模，该模型捕捉了硅片-衬垫相互作用和传感器信号响应之间的动态关系。将进行实验和分析调查以解决这些问题。一台生产机器将配备一系列异构传感器，包括力、温度、振动和声发射（有线和无线）。传感器融合方法将用于监测过程的各个阶段。机器特定和材料特定参数与性能变量（即去除率和平面性）之间的复杂关系将通过应用于实验数据的一套统计分析方法来描述。利用积家经典热源理论、吉布斯自由能最小化和分子动力学模型，建立热模型，确定不同温度下晶圆衬垫界面的机械和化学相互作用。半导体器件精加工的生产率提高取决于化学机械刨平/抛光技术的进步。晶圆尺寸、器件密度、特征尺寸、表面质量和缺陷结构对化学机械刨光/抛光科学技术提出了严峻的挑战。这项研究如果成功，将对各种化学-机械相互作用产生更深入的见解，并将集成异构传感器网络，以提高生产率和集成电路质量。

The objective of this research project is to address the following issues involved in the predictive modeling and real-time monitoring of chemical mechanical planarization/polishing (CMP) process used in the finishing of semiconductor chips: the interaction of chemical and mechanical phenomena at the silicon wafer-pad interface, the effect of machine vibrations, forces, temperature profiles, and acoustic emission signals, and the modeling of nonlinear stochastic process-machine interactions that capture the dynamic relationships between the wafer-pad interactions and the response of the sensor signals. Both experimental and analytical investigations will be undertaken to address these issues. A production machine will be instrumented with an array of heterogeneous sensors, including force, temperature, vibration, and acoustic emission (both wired and wireless). A sensor fusion approach will be used to monitor various stages of the process. The complex relationships connecting machine-specific and material-specific parameters with performance variables, namely, removal rate and planarity will be delineated by the application of a suite of statistical analysis methods applied to the experimental data. The mechanical and chemical interactions at the wafer-pad interface at various temperatures will be determined by developing a thermal model using Jaeger's classical heat source theory, Gibbs free-energy minimization, and molecular dynamics modeling.Productivity gains in the finishing of semiconductor devices depend on advances in chemical mechanical planarization/polishing. Wafer sizes, device density, feature dimensions, surface quality, and defect structure are posing serious challenges to the science and technology of chemical mechanical planarization/polishing . This investigation, if successful, will yield deeper insights into various chemo-mechanical interactions and will integrate a heterogeneous sensor network for improving productivity and integrated circuit quality.