Hybrid Standard Cell Structure for Dense Gate-All-Around IC Layout

The patent segments standard cells into different size categories (large and small cells) with distinct active region widths. Small cells have narrower active regions and can be placed closer together, while large cells have wider active regions. This segmentation allows the spacing rules to be applied selectively rather than uniformly, improving packing density while maintaining process window for each cell type.

The patent applies different spacing requirements locally to different cell types rather than using a uniform spacing rule across all cells. Small cells with narrower active regions have different spacing requirements compared to large cells with wider active regions. This local quality approach allows optimized packing density in regions with small cells while maintaining adequate process window through appropriate spacing where required.

The patent segments the standard cell library into different performance categories based on active region width. Small cells with narrower active regions are optimized for high-speed performance and can be placed in performance-critical paths, while large cells with wider active regions provide robustness for less critical functions. This segmentation allows the design to achieve high overall device performance while maintaining process window through appropriate cell selection and placement.

The patent changes the active region width parameter to create different cell types with distinct performance characteristics. Small cells have narrower active regions that enable faster switching speeds, while large cells have wider active regions that provide better manufacturing yield. By varying this parameter and allowing different cell types to coexist, the patent achieves both high device performance and adequate process window.

The patent segments the standard cell library into a manageable two-category classification (small and large cells) based on active region width. This limited segmentation provides enough variety to achieve high packing density while avoiding the complexity of having many different cell types. The simple binary classification makes it easier to manage device complexity compared to having numerous dimensional variations.

The patent creates a universal standard cell library structure where both small and large cells follow the same basic design rules and can be placed using the same methodology. This universality allows the hybrid structure to achieve high packing density without proportionally increasing device complexity, as the same placement and routing tools can handle both cell types.