Method of tiling analog circuits
AssigneeFreescale Semiconductor, Inc.
InventorsJames McClellan, Patrick Drennan, Douglas Garrity, David LoCascio, Michael McGowan
Life of this patent
Estimating the term…
Abstract
The present invention provides a method for tiling an integrated circuit having a critically matched device such as a transistor. The method obtains an advantage of automatically improving metallic density over critically matched devices thus yielding improved CMP. The method may include the steps of: identifying critically matched devices in the integrated circuit; placing metal tiles over the critically matched device; performing a density test around each critically matched device; and if a density test is not satisfied around a critically matched device, placing at least one metal strip over a critically matched device.
Claims20
A method for placing tiles in an integrated circuit having critically matched devices, the method comprising the steps of:
- identifying critically matched devices in the integrated circuit;
- calculating a metal spacing for tiles in the integrated circuit;
- calculating a lateral spacing for tiles in the integrated circuit;
- placing tiles around the critically matched devices based on the metal spacing and the lateral spacing;
- performing a density test over each critically matched device;
- and
- if a density test is not satisfied over a critically matched device, placing at least one metal strip over a critically matched device.
An integrated circuit comprising:
- at least one critically matched device having an area of symmetry;
- and
- at least one metal strip placed over a critically matched device so as to substantially overlie the area of symmetry.
A system for automatically placing tiles in an integrated circuit having critically matched devices, the system comprising:
- means for inputting data to the system;
- means for outputting data from the system;
- a memory;
- and
- a processor linked to the means for inputting, means for outputting, and memory, and wherein the processor is configured so as to
- identify critically matched devices;
- calculate a metal spacing for tiles in the integrated circuit;
- calculate a lateral spacing for tiles in the integrated circuit;
- place tiles around the critically matched devices;
- determine whether a density test is satisfied over each critically matched device;
- and
- if a density test is not satisfied, place at least one metal strip over a critically matched device that does not satisfy the density test.
Dependencies are inferred from the claim text.