US Patent 7757190 Design rules checking augmented with pattern matching

Layout patterns are identified as problematic when they have particular parameters required to exceed standard limits. The problematic layout patterns are associated with preferred design rules in a DRC-Plus deck. Layout data is scanned to generate match locations of any problematic layout patterns. The match locations are forwarded to a DRC engine that compares layout parameters of the match locations to corresponding preferred layout rules in the DRC-Plus deck. The DRC-Plus check results are used to modify the layout to improve manufacturability of the layout.