US 9,436,793 B2 · Tier based layer promotion and demotion

Abstract

Among other things, one or more systems and techniques for tier based layer modification, such as promotion or demotion, for a design layout are provided herein. A metal scheme describes one or more metal layers of the design layout, which are grouped into a set of tiers based upon resistivity similarity between the metal layers. Wire segments of the design layout are evaluated for promotion to tiers providing improved performance, for demotion to tiers providing decreased performance so that relatively faster routing resources are freed up for other wire segments, or for modification such as widening of wire segments. Via count penalties corresponding to timing delays of additional vias used to reassign wire segments are taken into account during promotion. Routing resource gains associated with reassigning wire segments are taken into account during demotion. In this way, wire segments of the design layout are promoted, demoted, or modified.

Claims20

Dependent claims

A method for tier based layer modification for a design layout, comprising:

evaluating a metal scheme for a design layout to group metal layers of the design layout into a set of tiers based upon a resistivity associated with the respective metal layers;
identifying a first net within the design layout, the first net comprising a first wire segment;
determining a current performance for the first wire segment based upon a current tier, of the set of tiers, to which the first wire segment is assigned;
determining a potential performance for the first wire segment based upon a potential tier, of the set of tiers, to which the first wire segment could be reassigned;
evaluating the current performance and the potential performance to either retain an assignment of the first wire segment to the current tier or reassign the first wire segment to the potential tier;
and
forming the first wire segment within an integrated circuit according to the design layout, wherein:
the first wire segment is formed within a metal layer of the current tier when the assignment of the first wire segment to the current tier is retained;
and
the first wire segment is formed within a metal layer of the potential tier when the first wire segment is reassigned to the potential tier.

7 more elements

A non-transitory computer readable medium comprising instructions that when executed perform operations, comprising:

evaluating a metal scheme for a design layout to group metal layers of the design layout into a set of tiers;
identifying a first net within the design layout, the first net comprising a first wire segment;
determining a current performance for the first wire segment based upon a current tier to which the first wire segment is assigned;
determining a potential performance for the first wire segment based upon a demotion tier to which the first wire segment could be reassigned, the determining comprising:
identifying a routing resource gain associated with reassigning the first wire segment to the demotion tier;
and
specifying the potential performance based upon the routing resource gain;
evaluating the current performance and the potential performance to either retain an assignment of the first wire segment to the current tier or reassign the first wire segment to the demotion tier;
and
forming the first wire segment within an integrated circuit according to the design layout, wherein:
the first wire segment is formed within a metal layer of the current tier when the assignment of the first wire segment to the current tier is retained;
and
the first wire segment is formed within a metal layer of the demotion tier when the first wire segment is reassigned to the demotion tier.

10 more elements

Dependencies are inferred from the claim text.

Tier based layer promotion and demotion

Life of this patent

Tier based layer promotion and demotion

Life of this patent

Abstract

Claims20