Local Interconnect is incorporated into some of the new deep submicron processes. In the case discussed here, this layer is drawn at a constant width, and it electrically connects to either Diffusion or Poly without an intervening contact geometry. The electrical interface thus formed is rectangular in shape. The minimum requirement for the length of this rectangle is related to how likely this rectangularly-shaped interface is to be degraded by normal mask misregistration which occurs as the chip is fabricated. A shape whose long edge comes closer to extending beyond the edge of the Diffusion or Poly shape must be greater in length than a shape that is immune to degradation from misalignment. Essentially, the length of the rectangular interface varies inversely with how close it comes to the boundary of the underlying layer. For DRC purposes, this rule is expressed in a multi-line table format where each line defines three minimal parameters for a legal interface between Local Int and the underlying layer. We describe an SVRF implementation of this check which delivers good performance and which is applicable to an entire class of similar rule requirements.

Bio

John Bartholomew has been employed since June 1998 as an Application Engineer in the Austin office of Mentor Graphics, supporting the Physical Extraction and Verification line of tools. Prior to that he worked at Motorola for 12 years in the areas of hierarchical verification, layout automation, and various aspects of physical CMOS IC design. When in the Portland area, he enjoys attending performances by songwriter/pianist Dave Frishberg.