Optical proximity correction method for intermediate-pitch features using sub-resolution scattering bars on a mask
DCFirst Claim
1. A method of providing non-resolvable correction features on a mask for correcting for proximity effects, said mask including at least two feature edges, said correction features having an associated nominal width, associated nominal spacing from a given mask feature edge, and an associated nominal spacing between adjacent correction feature edges, said method comprising the steps of:
- adding a single non-resolvable correction feature between two adjacent mask edges on a mask, said correction feature having an edge adjacent to each of said two adjacent mask edges, wherein said adjacent correction feature edges are spaced a distance from said two adjacent edges that is less than said nominal spacing but greater than a given minimum distance;
adding two non-resolvable correction features between two adjacent edges on a mask wherein said correction feature is spaced a distance from each of said two adjacent edges that is less than said nominal spacing but greater than a given minimum distance.
4 Assignments
Litigations
0 Petitions
Accused Products
Abstract
A method for providing scattering bars for optical proximity effect correction on a mask used in a lithographic process. Scattering bar spacing and characteristics are adjusted and varied along with primary feature edge location in order to control CD'"'"'s of features that are spaced a distance greater than the minimum pitch of a lithographic process but less than a nominal distance for two feature edges having independent scattering bars.
257 Citations
25 Claims
-
1. A method of providing non-resolvable correction features on a mask for correcting for proximity effects, said mask including at least two feature edges, said correction features having an associated nominal width, associated nominal spacing from a given mask feature edge, and an associated nominal spacing between adjacent correction feature edges, said method comprising the steps of:
-
adding a single non-resolvable correction feature between two adjacent mask edges on a mask, said correction feature having an edge adjacent to each of said two adjacent mask edges, wherein said adjacent correction feature edges are spaced a distance from said two adjacent edges that is less than said nominal spacing but greater than a given minimum distance; adding two non-resolvable correction features between two adjacent edges on a mask wherein said correction feature is spaced a distance from each of said two adjacent edges that is less than said nominal spacing but greater than a given minimum distance. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A method of applying at least one correction feature having associated physical characteristics to correct for proximity effects of two adjacent primary features spaced apart a given distance in a lithographic process using an exposure tool having an associated wavelength and having an associated resolution limit which is dependent on processing parameters of said lithographic process, said primary features each having an associated edge adjacent to said at least one correction feature and said each adjacent edge having an original placement, said method comprising the steps of:
-
placing said at least one correction feature between said two adjacent features; adjusting at least one of said associated physical characteristics of said at least one correction feature and said original placement of at least one of said adjacent edges so that the separation space between said each adjacent edge and said at least one correction feature is a distance that is greater than a minimum distance and less than a given nominal distance which is in the range of said resolution limit of said lithographic process, wherein said minimum distance is less than said wavelength. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15)
-
-
16. A method using at least one correction feature having an associated width to correct for proximity effects of two adjacent primary features on a mask in a lithographic process using an exposure tool having an associated wavelength (λ
- ) and having an associated maximum unresolvable width which is dependent on processing parameters of said lithographic process, said primary features being spaced apart a given distance and each having an associated edge adjacent to said at least one correction feature and said each adjacent edge having an original placement, said method comprising the steps of;
determining a number of correction features to be placed between said two primary features so that the separation space between each of said adjacent edges of said primary features and an adjacent one of said at least one correction feature is a distance that is greater than a minimum distance and less than a given nominal distance which is in the range of said resolution limit of said lithographic process, wherein said minimum distance is less than said wavelength; placing said number of correction features between said two adjacent features. - View Dependent Claims (17, 18, 19, 20, 21, 22, 23, 24, 25)
- ) and having an associated maximum unresolvable width which is dependent on processing parameters of said lithographic process, said primary features being spaced apart a given distance and each having an associated edge adjacent to said at least one correction feature and said each adjacent edge having an original placement, said method comprising the steps of;
Specification