Layouts with routes with different widths in different directions on the same layer, and method and apparatus for generating such layouts

• US 7,096,449 B1
• Filed: 08/26/2002
• Issued: 08/22/2006
• Est. Priority Date: 01/22/2002
• Status: Expired due to Fees

• Current Assignee: Cadence Design Systems Incorporated (Cadence Group)
• Original Assignee: Cadence Design Systems Incorporated (Cadence Group)
• Inventors: Teig, Steven, Jacques, Etienne
• Primary Examiner(s): Thompson, A. M.
• Assistant Examiner(s): Dimyan, Magid Y.
• Application Number:
  US10/229,202
• Time in Patent Office: 1,457 Days
• Field of Search: 716 12- 15
• US Class Current: 716/129
• CPC Class Codes: G06F 30/394 Routing G06F30/396 takes precedence

Abstract

Some embodiments of the invention provide a method of routing nets in a multi-layer integrated-circuit (“IC”) layout. For a particular net, the method specifies widths for routing the particular net in different directions on the same layer. It then defines a particular route for the particular net, where the route has different widths in the different directions on the same layer.

Claims

1. A multi-layer integrated-circuit (“

IC”

) layout comprising a route that traverses different directions on a particular layer, wherein the route has a first segment in a diagonal first direction and a second segment in a Manhattan second direction, wherein the first segment is wider than the second segment on the particular layer.

2. A multi-layer integrated-circuit (“

IC”

) layout comprising;

a) a plurality of nets having a plurality of routable elements;

b) a plurality of routes for connecting the routable elements of nets, wherein the routes traverse a plurality of directions on a particular layer; and

c) said plurality of routes having a set of routes, wherein each route in the set has first and second segments on the particular layer, wherein the first segment is in a diagonal first direction and the second segment is in a Manhattan second direction, wherein the first segment is wider than the second segment.

3. The IC layout of claim 2, wherein a plurality of the routes are specified based on design rules that specify different widths for routes in different directions on the particular layer.

4. The IC layout of claim 3, wherein the design rules specify for at least two routes different widths in the same direction on the particular layer.

5. The IC layout of claim 2, wherein the diagonal direction is a 45°

diagonal direction.

6. The IC layout of claim 2, wherein a particular route is snapped to a manufacturing grid, and the snapping of the particular route to the manufacturing grid makes the width of the route in the different direction different.

7. The IC layout of claim 2, wherein the layout is the layout of a single integrated circuit.

8. The IC layout of claim 2, wherein the layout is the layout of a portion of a single integrated circuit.

9. A method of routing nets in a multi-layer integrated-circuit (“

IC”

) layout, the method comprising;

a) for a particular net, specifying different widths for routing the particular net in different directions on a particular layer; and

b) defining a particular route for the particular net, wherein the particular route has a first segment in a diagonal first direction on the particular layer and a second segment in a Manhattan second direction on the particular layer, wherein the first segment is wider than the second segment.

10. The method of claim 9 further comprising:

a) for each particular net in a set of nets, specifying different widths for routing the particular net in different directions on the particular layer; and

b) defining a route for each net in the set, wherein the route of each of a plurality of nets in the set has different widths in the different directions on the particular layer.

11. The method of claim 10, wherein specifying different widths for routing the nets comprises specifying for at least two routes different widths in the same direction on the particular layer.

12. The method of claim 10, wherein the diagonal direction is a 45°

diagonal direction.

13. The method of claim 9, wherein defining the route comprises snapping the route to a manufacturing grid, wherein the snapping of the route to the manufacturing grid makes the width of the route in the different direction different.

14. A computer readable medium storing a computer program for routing nets in a multi-layer integrated-circuit (“

IC”

) layout, the computer program comprising instructions for;

a) specifying, for a particular net, different widths for routing the particular net in different directions on the particular layer;

b) defining a particular route for the particular net, wherein the particular route has a first segment in a diagonal first direction on the particular layer and a second segment in a Manhattan second direction on the particular layer, wherein the first segment is wider than the second segment.

15. The computer readable medium of claim 14, wherein the computer program further comprises instructions for:

a) specifying, for each particular net in a set of nets, different widths for routing the particular net in different directions on the particular layer; and

b) defining a route for each net in the set, wherein the route of each of a plurality of nets in the set has different widths in the different directions on the particular layer.

16. The computer readable medium of claim 15, wherein the instructions for specifying different widths for routing the nets comprises instructions for specifying for at least two routes different widths in the same direction on the particular layer.

17. The computer readable medium of claim 14, wherein the instructions for defining the route comprises instructions for snapping a particular route to a manufacturing grid, wherein the snapping of the particular route to the manufacturing grid results in the width of the route being different in different directions.