Layout overlap detection with selective flattening in computer implemented integrated circuit design
US6011911A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 1997 |
| Grant date | Jan 4, 2000 |
| Priority date | — |
| Expiry date | Sep 30, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F30/398
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a method for efficiently performing hierarchical design rules checks (DRC) and layout versus schematic comparison (LVS) on layout areas of an integrated circuit where cells overlap or where a cell and local geometry overlap. With the present invention, a hierarchical tree describes the integrated circuit's layout data including cells having parent-child relationships and including local geometry. The present invention performs efficient layout verification by performing LVS and DRC checking on the new portions of an integrated circuit design and layout areas containing overlapping cells. When instances of cells overlap, the present invention determines the overlap area using predefined data structures that divide each cell into an array of spatial bins. Each bin of a parent is examined to determine if two or more cell instances reside therein or if a cell instance and local geometry reside therein. Once overlap is detected, the areas of the layout data corresponding to the overlap areas are selectively flattened prior to proceeding to DRC and LVS processing. During selective flattening of the overlap areas, the hierarchical tree is traversed from th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.