PITA Fiscal Year 2008 Projects - Nanotechnology

Development of an Integrated, Multiphenomena Simulation Tool for Chemical Mechanical Polishing Systems

Principal Investigators: Myung S. Jhon, C. Fred Higgs, III

To reduce production cost in semiconductor manufacturing, the size of wafer gets larger. At the same time, the need for much thinner and more compact nanofabrication requires more precision machining. In manufacturing of advanced semiconductor devices, the CMP process is one of the most important intermediate fabrication steps. The CMP engineers face difficulties in scale-up of current wafer size, caused by lack of thorough understanding of the process. Representative physical phenomena in addition to complex geometries include non-Newtonian slurry flow with chemical reactions, contact mechanics, and particle motions which all lead to material wear. Therefore, it is a great challenge to develop an integrated complex multiphenomena simulation tool which can be used in a nanomanufacturing environment. In our previous work, we developed a novel lattice Boltzmann method (LBM) tool for the prediction of Newtonian/non-Newtonian flow with arbitrary boundary conditions. Further, we have developed a primitive integrated model with fluid dynamics, simple yet physically realistic particle dynamics and contact mechanics in an isothermal environment. LBM is advantageous over conventional computational fluid dynamics (CFD) since it is intrinsically transient, easy to parallelize, capable of complex geometry handling, and easy in incorporating complex physical phenomena. Therefore, integrated multiphenomena LBM will become a natural choice. We first propose to develop an LBM scheme for multiphase phenomena, which includes an accurate description of particle trajectories. Later, we will construct the integrated model which is useful for multiphase, chemically reactive fluid in a non-isothermal environment equipped with a realistic wear model. A CMP modeling test case, e.g., uniform slurry feeder, will be examined as a benchmark application. The development of a realistic integrated LBM-based CMP model will enhance our modeling capabilities of the complex phenomena and thus help the engineers, such as those at PPG, to design advanced CMP equipment and consumables.