Fluorinated CMP Pad With Multimodal Grooves for STI Planarization

The patent applies local quality by creating a non-uniform groove pattern where different regions of the polishing pad have different groove characteristics. Specifically, there are first grooves with a first cross-sectional area and second grooves with a second cross-sectional area that is less than 50% of the first groove cross-sectional area. This local variation in groove geometry allows different areas of the pad to perform different functions - some areas provide higher removal rate while others maintain planarity, thus resolving the contradiction between these two requirements.

The patent applies parameter changes by modifying the physical and chemical parameters of the polishing pad material. Specifically, it uses a fluorinated polyurea polymer with controlled molecular weight and composition, and creates a groove pattern with specific geometric parameters (cross-sectional area ratios, groove depths, groove spacings). These parameter changes enable the pad to achieve high removal rates even at low downforce pressures below 30 kPa, while maintaining low defect occurrence and good planarity.

The patent applies mechanics substitution by replacing reliance on high mechanical downforce with a chemically enhanced mechanical system. The fluorinated polyurea polymer material provides chemical mechanical polishing action through its specific molecular structure and interaction with the slurry, enabling effective material removal at low mechanical pressures. This substitutes the need for high downforce (which causes defects) with a chemically active material that removes material effectively through chemical-mechanical interaction rather than pure mechanical compression.