	US 11,860,531 B2
	Skeleton representation of layouts for the development of lithographic masks
Thomas C. Cecil, Menlo Park, CA (US); and David W. Thomas, Sunnyvale, CA (US)
Assigned to Synopsys, Inc., Sunnyvale, CA (US)
Filed by Synopsys, Inc., Mountain View, CA (US)
Filed on Feb. 19, 2021, as Appl. No. 17/180,653.
Application 17/180,653 is a continuation of application No. PCT/US2021/018034, filed on Feb. 12, 2021.
Claims priority of provisional application 62/977,020, filed on Feb. 14, 2020.
Prior Publication US 2021/0255539 A1, Aug. 19, 2021
Int. Cl. G03F 1/36 (2012.01)

CPC G03F 1/36 (2013.01)

20 Claims

1. A method comprising:

accessing a layout used in a mask development process for a lithographic mask, the layout comprising a plurality of disjoint shapes;

determining, by a processor, skeleton representations for at least some of the disjoint shapes in the layout, wherein the skeleton representation of an individual shape comprises elements of two or more nodes connected by edges, and size parameters for at least some of the elements, wherein each edge connects two of the nodes by a straight line, and all of the edges and nodes lie within an interior of the individual shape; and

using the skeleton representations in the mask development process.