Method for generating proximity correction features for a lithographic mask pattern

In a lithographic pattern generation system where a mask pattern having a plurality of features is represented by pattern data, said pattern data being formatted in a non-hierarchical pattern representation where each feature of said plurality of features is enumerated, said each feature having corresponding edges and vertices, a method for synthesizing serif and bar correction features for each feature, said method including the steps of:

• 1) dividing said pattern data into a plurality of data sets, wherein each data set contains data corresponding to an overlapping section of features in said mask pattern;
• 2) processing one of said plurality of data sets through a bar synthesis phase wherein said bar synthesis phase formats said one data set's corresponding data into an edge representation and wherein said bar synthesis phase generates interior and exterior bar data for said corresponding edges of said each feature in said one data set, said exterior bar data being geometrically added to said one data set's corresponding data and said interior bar data being geometrically subtracted from said one data set's corresponding data;
• 3) processing said one data set through a serif synthesis phase wherein said serif synthesis phase formats said one data set's corresponding data into a vertex representation, and wherein said serif synthesis phase generates positive and negative serif data for each of said corresponding vertices of said each feature in said one data set, said positive serif data being geometrically added to said one data set's corresponding data and said negative serif data being geometrically subtracted from said one data set's corresponding data;
• 4) storing the resultant data from the geometric addition and subtraction operations performed in steps 2 and 3 in a pattern file, said pattern file for storing all of said pattern data having said serif and edge bar correction features applied to it;
• 5) performing steps 2-4 for another of said plurality of data sets, for the remainder of said plurality of data sets.

In a mask pattern having at least one feature represented by feature data, said at least one feature having associated edges, a method for synthesizing a bar correction feature for at least one of said associated edges, said bar correction feature being spaced a given distance from said at least one of said associated edges according to a given set of design rules associated with said mask pattern, said method including the steps of:

• displacing said at least one of said associated edges said given distance;
• expanding said at least one displaced edge to generate data corresponding to said bar correction feature having a width equal to a predetermined bar width;
• wherein, if said data corresponding to said at least one bar correction feature is an internal bar correction feature with respect to said feature data, said at least one bar correction feature data is geometrically subtracted from said feature data;
• and
• wherein, if said data corresponding to said at least one bar correction feature is an external bar correction feature with respect to said feature data, said at least one bar correction feature data is geometrically added to said feature data.

In a mask pattern having at least one feature represented by feature data, said at least one feature having associated edges, a method for synthesizing bar correction features for said associated edges, said bar correction features being spaced a given distance from said associated edges according to a given set of design rules associated with said mask pattern, said method including the steps of:

• displacing said associated edges said given distance to obtain first displaced feature data;
• displacing said first displaced feature data a second distance equal to a predetermined width of said bar correction features to obtain second displaced feature data;
• performing a geometric AND-NOT operation between said first displaced feature data and said second displaced feature data to obtain data corresponding to said bar correction features;
• wherein, if said data corresponding to said bar correction features corresponds to internal bar correction features with respect to said feature data, said bar correction feature data is geometrically subtracted from said feature data;
• and
• wherein, if said data corresponding to said bar correction features corresponds to external bar correction features with respect to said feature data, said bar correction feature data is geometrically added to said feature data.

In a mask pattern having a plurality of features represented by feature data, said mask pattern having clear and opaque areas, said plurality of features having associated edges, a method for synthesizing one of an internal and external bar correction feature for each of said associated edges, said one bar correction feature being spaced a given distance from said each associated edge according to a given set of design rules associated with said mask pattern, said method including the steps of:

• 1) changing the opaqueness of said opaque and clear areas into the opposite opaqueness for synthesizing said internal bar correction feature;
• 2) oversizing each of said plurality of features by said given distance to generate oversized feature data, wherein if said each feature corresponds to an opaque area, said opaque area is oversized and wherein if said each feature corresponds to a clear area, said clear area is oversized;
• 3) formatting said oversized feature data into an edge representation wherein said each associated edge is enumerated by edge data;
• 4) expanding said edge data to generate data corresponding to one of said internal and external bar correction feature, said one of said internal and external bar correction feature having a width equal to a predetermined bar width;
• 5) geometrically subtracting said data corresponding to said internal bar correction from said feature data for internal bar synthesis;
• 6) geometrically adding said data corresponding to said external bar correction feature to said feature data for external bar synthesis.