Patent ID: 8225239
Filing Date: 2012-07-17
Classification: G03F,G06F,Y02P

Abstract:
1. A method for using sub-resolution shapes placed on a virtual grate to reinforce regular layout shapes in a lithographic process, comprising: operating a computer to determine whether an unoccupied layout space within a level of a cell adjacent to a regular layout shape to be reinforced and extending in a direction perpendicular to the regular layout shape to be reinforced is large enough to support placement of a sub-resolution shape within the level of the cell, wherein the regular layout shape to be reinforced is placed in accordance with a virtual grate; upon determining that the unoccupied layout space is large enough to support placement of the sub-resolution shape, operating the computer to place the sub-resolution shape so as to be substantially centered upon a virtual line of the virtual grate within the unoccupied layout space within the level of the cell; upon determining that the unoccupied layout space is not large enough to support placement of the sub-resolution shape, operating the computer to evaluate whether one or more previously placed layout shapes within the level of the cell neighboring the unoccupied layout space are reconfigurable to enlarge the unoccupied layout space within the level of the cell so as to support placement of the sub-resolution shape within the unoccupied layout space within the level of the cell; operating the computer to reconfigure the one or more previously placed layout shapes within the level of the cell to enlarge the unoccupied layout space so as to support placement of the sub-resolution shape within the unoccupied layout space within the level of the cell; and operating the computer to place the sub-resolution shape so as to be substantially centered upon a virtual line of the virtual grate within the unoccupied layout space within the level of the cell.