International Business Machines Corporation

Xin Yuan

Kevin W McCullen

Robert F Walker

Xiaoping Tang

Jason D Hibbeler

Rani Narayan

Michael S Gray

Fook-Luen Heng

Robert J Allen

Cam V Endicott

Matthew Thomas Guzowski

Leon Jacob Sigal

Stephen Larry Runyon

Veit Gernhoefer

Pieter J Woeltgens

Xiaoyun K Wu

Approaches are provided for fixing pin mismatches from swapping library cells in layout migration. Specifically, a method is provided that includes collecting information about a first technology pin from a library cell in a first technology. The method further includes swapping the library cell in the first technology with a library cell in a second technology. The method further includes collecting information about a second technology pin from the library cell in the second technology. The method further includes building a pin-mapping table that is configured to map the first technology pin to the second technology pin. The method further includes scaling a layout from the first technology to the second technology. The method further includes modifying the layout based on the pin-mapping table to match the at least one first technology pin to the at least one second technology pin while satisfying ground rules of the second technology.

Systems and methods for fixing pin mismatch in layout migration

Solutions for optimizing an integrated circuit layout for implementation in an integrated circuit are disclosed. In one embodiment, a computer-implemented method is disclosed including: obtaining a plurality of hierarchical constraints in mathematical form, the plurality of hierarchical constraints defining a first integrated circuit layout; partitioning the plurality of hierarchical constraints into groups according to one or more partitioning rules; determining whether a boundary condition exists between two of the groups, and distributing a slack or a gap between the two of the groups in the case that the boundary condition exists; creating a plurality of integer linear programming problems associated with each of the groups; determining a solution for each of the plurality of integer linear programming problems; and integrating each solution together to form a second integrated circuit layout.

Parallel solving of layout optimization

An approach for decomposing a layout for triple patterning lithography is described. In one embodiment, a triple patterning conflict graph is built from a layout having pattern features specified as shapes. The triple patterning conflict graph represents the shapes in the layout and coloring constraints associated with the shapes. The shapes represented by the triple patterning conflict graph are decomposed into three colors to avoid color conflict, while balancing the color density among the three colors and minimizing a number of stitches used to represent the shapes in the layout. Color conflicts in the decomposition are resolved by selectively segmenting the shapes in the decomposition that are associated with the color conflict.

Decomposing layout for triple patterning lithography

A method, system and program product for migrating an integrated circuit (IC) design from a source technology without radical design restrictions (RDR) to a target technology with RDR, are disclosed. The invention implements a minimum layout perturbation approach that addresses the RDR requirements. The invention also solves the problem of inserting dummy shapes where required, and extending the lengths of the critical shapes and/or the dummy shapes to meet 'edge coverage' requirements.

Technology migration for integrated circuits with radical design restrictions

An approach that obtains a feasible integer solution in a hierarchical circuit layout optimization is described. In one embodiment, a hierarchical circuit layout and ground rule files are received as input. Constraints in the hierarchical circuit layout are represented as an original integer linear programming problem. A relaxed linear programming problem is derived from the original integer linear programming problem by relaxing integer constraints and using relaxation variables on infeasible constraints. The relaxed linear programming problem is solved to obtain a linear programming solution. Variables are then clustered, and at least one variable from each cluster is rounded to an integer value according to the linear programming solution. Next, it is determined whether all the variables are rounded to integer values. Unrounded variables are iterated back through the deriving of the integer linear programming problem, solving of the relaxed linear programming problem, and rounding of a subset of variables. A modified hierarchical circuit layout is generated in response to a determination that all the variables are rounded to integer values.

Methods to obtain a feasible integer solution in a hierarchical circuit layout optimization

A computer-implemented method for handling a plurality of constraints in layout optimization for an integrated circuit (IC) layout is disclosed. In one embodiment, the method includes building a graph representing the plurality of constraints; marking two-dimensional constraints in the plurality of constraints; generating two-dimensional clusters including groups of the two-dimensional constraints; handling at least one of the two-dimensional clusters, the handling including finding a solution for the two-dimensional constraints in the at least one two-dimensional cluster; repeating the handling for any unprocessed two-dimensional clusters until all of the two-dimensional clusters are handled; and adopting the solution for each of the two-dimensional clusters to solve at least a portion of the plurality of constraints including the two-dimensional clusters.

Handling two-dimensional constraints in integrated circuit layout

A system and method are disclosed for legalizing a flat or hierarchical VLSI layout to meet multiple grid constraints and conventional ground rules. Given a set of ground rules with multiple grid constraints and a VLSI layout (either hierarchical or flat) which is layout-versus-schematic (LVS) correct but may not be ground rule correct, the system and method provide a legalized layout which meets the multiple grid constraints while maintaining LVS correctness and fixing the ground rule errors as much as possible with minimum layout perturbation from the input design. The system and method support multiple grid pitch constraints for hierarchical design, and provide for LVS correctness to be maintained while an on-grid solution possibly with some spacing violations.

VLSI artwork legalization for hierarchical designs with multiple grid constraints

An adaptive weighting method for layout optimization differentiates different priorities by assigning the weight of a higher priority (p) to be multiple of the weight of a lower priority (p) where W(p)=m% W(p. To avoid numerical imprecision, this method keeps the total cost in the objective function within a trustable range by scaling the initial weights in the objectives, while maintaining relativity, to produce the scaled weights.

Adaptive weighting method for layout optimization with multiple priorities

An approach that obtains a feasible integer solution in a hierarchical circuit layout optimization is described. In one embodiment, a hierarchical circuit layout and ground rule files are received as input. Constraints in the hierarchical circuit layout are represented as an original integer linear programming problem. A relaxed linear programming problem is derived from the original integer linear programming problem by relaxing integer constraints and using relaxation variables on infeasible constraints. The relaxed linear programming problem is solved to obtain a linear programming solution. A subset of variables from the relaxed linear programming problem is rounded to integer values according to the linear programming solution. Next, it is determined whether all the variables are rounded to integer values. Unrounded variables are iterated back through the deriving of the integer linear programming problem, solving of the relaxed linear programming problem, and rounding of a subset of variables. A modified hierarchical circuit layout is generated in response to a determination that all the variables are rounded to integer values.

Obtaining a feasible integer solution in a hierarchical circuit layout optimization

A method, system and program product for context aware sub-circuit layout modification are disclosed. The method may include defining at least one context for the sub-circuit for each circuit that uses the sub-circuit; in the case that a plurality of contexts are defined, minimizing a number of contexts for the sub-circuit by combining contexts into at least one stage; placing each stage into a staged layout; and modifying the sub-circuit by modifying the staged layout.

Context aware sub-circuit layout modification

A method, system and program product for migrating an integrated circuit (IC) design from a source technology without radical design restrictions (RDR) to a target technology with RDR, are disclosed. Also, a method, system and program product for migrating an integrated circuit design from a source technology without RDR to a target technology with RDR in which space may be reserved for late insertion of a feature and in which migration first occurs in a primary compaction direction having less tolerant ground rules.

Methods of independently migrating a hierarchical design are disclosed. A method for migrating a macro in an integrated circuit comprises: determining an interface strategy between a base cell in the macro and the macro, the base cell including an interface element involved in the interface strategy; migrating the base cell independently with respect to the macro based on the interface strategy; initially scaling the macro; swapping the migrated base cell into the macro; and legalizing content of the initially scaled macro.

Independent migration of hierarchical designs with methods of finding and fixing opens during migration

A method comprises extracting a hierarchical grid constraint set and modeling one or more critical objects of at least one cell as a variable set. The method further comprises solving a linear programming problem based on the hierarchical grid constraint set with the variable set to provide initial locations of the critical objects of the at least one cell and determining target on-grid locations of the one or more critical objects in the at least one cell using the results of the linear programming solution.

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Williston, VT, United States of America

Xin Yuan