The Theoretical Analysis for the Effect of porous structure of pad on the Slurry Flows and Tribological Performances Arising at the Chemical Mechanical Polishing of Cu-Film Wafers

• Main Authors: Mow-Ren Tzeng, 曾茂仁
• Other Authors: Jen-Fin Lin
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/79264822129796314840

碩士 === 國立成功大學 === 機械工程學系碩博士班 === 93 === Abstract 　There are many parameters that effect the CMP in the process. The rule that porous structure of pad plays in CMP is very complicated and there are not many researches mentioned about it. Actually the porous structure of pad is significant for removing rate and uniformity of wafer after CMP. The theoretic simulation for flow field due to porous structure is established in this study. The method can be helpful for removing rate and uniformity of CMP. A valid method of evaluating the effect of porous structure to CMP is presented, too. 　The established model is considered for the effect of porous structure to both of the flow field and the contact mechanism among wafer, slurry, and pad. For the analysis of flow field, the Reynolds equation considered for effects of the porous structure is established. Numerical computing for theoretic analysis can solve the hydrodynamic pressure, liquid film thickness, and fluid velocity filed. For solid contact, the model for removing rate, which calculates deformation of pad roughness and substrate and includes abrasive and adhesive behaviors of wear, is established according to elastroplastic deformation theory. 　Using the Laplace Equation of Soil Mechanics to solve the hydro pressure in the field of pad. Computing the hydro pressure and hydrodynamic load by numerical analysis for the modified Reynolds equation. In the otherhand, evaluating the true contact pressure, contact area, and deformation between pad and wafer by analysis for the interface contact phenomena. There are several conclusions in this study. The porous structure increases removing rate more than uniformity. The smaller hardness of passivation, the larger removing rate and uniformity. According to the elastroplastic deformation theory of micro contact mechanics, we derive the contact pressure under polishing and solve the minimum fluid film thickness, attack angle, and rotating angle in equilibrium of force and moment.