Author_Institution :
Dept. of Mech. Eng., Univ. of California, Berkeley, CA, USA
Abstract :
Recently, a comprehensive model has been developed by Luo and Dornfeld ("Material removal mechanism in chemical mechanical polishing: theory and modeling", IEEE Trans. Semiconduct. Manufact., vol. 14, pp. 112-133, May 2001) to explain the material removal mechanism in chemical mechanical planarization (CMP). Based on the model, the abrasive size distribution influences the material removal from two aspects, one, the number of active abrasives, and the other, the size of the active abrasives. In this paper, experimental evidence supporting this view of abrasive size effects is discussed. A detailed model of wafer-abrasive-pad contact is developed to explain how and where abrasive size distributions come into the comprehensive material removal model. A material removal rate formulation as a function of abrasive size distribution is proposed and verified. In the future, the application of the model to the CMP process optimization, for example, improving the nonuniformity, or obtaining minimum surface scratching and preferred material removal rate by changing abrasive size distribution, may be attempted.
Keywords :
abrasion; chemical mechanical polishing; particle size; planarisation; semiconductor process modelling; abrasive size distribution; chemical-mechanical planarization; material removal model; process optimization; semiconductor manufacturing; wafer-abrasive-pad contact; Abrasives; Chemicals; Copper; Cutting tools; Dielectric materials; Fabrication; Planarization; Semiconductor device modeling; Semiconductor materials; Surface topography;
