Papers by Keyword: Contact Pressure Distribution

Abstract: In order to make the contact pressure distribution of polishing wafer surface more uniform during chemical mechanical polishing (CMP), a kind of the bionic polishing pad with sunflower seed pattern has been designed based on phyllotaxis theory, and the contact model and boundary condition of CMP have been established. Using finite element analysis, the contact pressure distributions between the polishing pad and wafer have been obtained when polishing silicon wafer and the effects of the phyllotactic parameter of polishing pad on the contact pressure distribution are found. The results show that the uniformity of the contact pressure distribution can be improved and the singularity of the contact pressure in the boundary edge of polished wafer can be decreased when the reasonable phyllotactic parameters are selected.

Abstract: In order to obtain the contact pressure distribution between the hard disc substrate and the polishing pad and its effects on the profile of polished substrate surface, the elastic contact mechanical model and mathematical equations on the chemical mechanical polishing of the hard magnetic disc substrate are established, and also the relevant boundary conditions are put forward. The contact pressure distribution is calculated with FEM, the polishing experiments are carried out and the surface profiles of polished substrates are obtained. The study results show that the contact pressure distribution on the substrate surface is non-uniformity and the contact pressure in the substrate edge present biggish undulation. Choosing properly the Young’s modulus of the polishing pads and decreasing its Poisson’s ratios can make the uniform area of the contact pressure distribution enlarging and improve the flatness of polished substrate.