Patent attributes
A polishing pad having a polishing surface, a back surface and a sidewall is provided. The sidewall is connected to the polishing surface and the back surface. The polishing pad includes a polishing region and a region neighboring to the polishing region. Wherein, at least one stress buffer pattern is designed in the neighboring region. The stress buffer pattern is formed to buffer the stress created during a polishing process to prevent the region from being protruded and thus prevent the surface of the region, once protruded, from rubbing against the wafer carrier to generate particles, so that contamination of the surface of the wafers can be avoided. On the other hand, at least one cambered surface can be designed on the sidewall of the polishing pad to prevent the sidewall from rubbing against the wafer carrier to generate particles, so that contamination can be avoided.