Collaborative Research: Wire Sawing - Mechanics and Design Space Exploration

本项目的研究目标是了解线切割硅片中长波长波纹的基本机理，并研究金刚石涂层线材中金刚石拔出的条件。还将调查这种拔出对线锯晶片表面质量和完整性的影响。将采用分析和数值模拟相结合的方法。将建立用于产生长波长波纹的流固耦合模型，并将进行热力耦合分析以预测金刚石的拔出条件。模拟结果将与实验室条件下的实验观测结果进行验证。然后将利用经过验证的机械模型来开发用于线切割过程的集成过程模型和控制算法。目前的线锯切割方法在晶片表面留下了长波长的波纹，必须通过昂贵的研磨工艺来校正。如果成功，该项目将改进线切割工艺，大大减少诱导波纹，从而减少研磨的需要，提高硅片生产的成本效益。磨料拔出影响砂轮的性能，建立磨料拔出的机理模型将有助于磨削工艺的设计。这些结果将对集成电路行业具有相当大的价值，特别是在该行业向更大的晶圆直径和更精细的电路结构发展的时候。

The research goals of this project are to understand the fundamental mechanics of the long wavelength waviness in wire sawed silicon wafers and to investigate the conditions for diamond pull-out from diamond coated wires. The implications of such pull-outs on surface quality and integrity of wire sawed wafers will also be investigated. A combination of analytical and numerical simulations will be pursued. A fluid-structure interaction model will be developed for long wavelength waviness generation, and a coupled thermo-mechanical analysis will be pursued for predictions of diamond pull-out conditions. Simulation results will be verified against experimental observations under laboratory conditions. Verified mechanistic models will then be utilized to develop integrated process models and control algorithms for the wire sawing process.The current wire sawing method of wafer slicing leaves a long wavelength waviness on the wafer surface that must be corrected by an expensive lapping process. If successful, this project will improve the wire sawing process to greatly reduce the induced waviness, thereby reducing the need for lapping, and enhancing the cost effectiveness of wafer production. Abrasive pull-out affects the performance of grinding wheels, and a mechanistic model of this phenomenon will aid in grinding process design as well. These results will be of considerable value to the integrated circuit industry, particularly as the industry goes to bigger wafer diameters and finer circuit structures.