Method and system for forming a pattern using charged particle beam lithography with multiple exposure passes which expose different surface area

A method for manufacturing an integrated circuit using an optical lithographic process, the optical lithographic process using a reticle, the method comprising:

• a) providing a shaped beam charged particle beam system;
• b) setting a base dosage level for an exposure pass;
• c) exposing a plurality of shaped beam shots for the exposure pass using the set base dosage level;
• and
• d) repeating b) and c) for at least one additional exposure pass,
• wherein the sum of the pluralities of shots for all of the exposure passes forms a set of desired patterns on the reticle, and wherein the union of the plurality of shaped beam shots for any exposure pass is different than the union of the pluralities of shaped beam shots for all of the exposure passes.

A system for fracturing or mask data preparation or proximity effect correction for use with shaped beam charged particle beam lithography comprising:

• an input device configured to receive a set of patterns to be formed on a surface;
• a computation device configured to determine a set of shaped beam shots that can be used to form the set of patterns using a plurality of exposure passes, wherein the set of shaped beam shots comprises a plurality of shaped beam shots for each of a plurality of exposure passes, and wherein the union of the plurality of shaped beam shots for any exposure pass in the plurality of exposure passes is different than the union of the pluralities of shaped beam shots for all of the exposure passes;
• and
• an output device configured to output the determined set of shaped beam shots.