Patent · US Expired

Selective flattening in layout areas in computer implemented integrated circuit design

US6009250A · kind A · utility

86Cited by
10References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 30, 1997
Grant dateDec 28, 1999
Priority date
Expiry dateSep 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.