Dummy insertion for improving throughput of electron beam lithography

A charged particle beam lithography system comprising:

• a data processing unit configured to:
• receive an integrated circuit (IC) design layout having a target pattern,
• determine a pattern density of pattern areas of the IC design layout, and
• insert a dummy feature into any pattern area having a pattern density that is less than a threshold pattern density, thereby generating a dummy pattern for the IC design layout, and
• generate an exposure map based on the IC design layout having the target pattern and the dummy pattern;
• and
• an charged particle beam exposure unit configured to expose an energy sensitive layer to a charged particle beam based on the exposure map.

A charged particle beam lithography system comprising:

• a stage configured to secure a workpiece having an energy sensitive layer;
• and
• a charged particle beam exposure unit configured to:
• expose a first region of the energy sensitive layer that corresponds with a target feature to a first dose of a charged particle beam, wherein the target feature is in a target pattern area of an integrated circuit (IC) design layout,
• expose a second region of the energy sensitive layer that corresponds with a dummy feature to a second dose of the charged particle beam, wherein the dummy feature is in the target pattern area of the IC design layout,
• wherein the first dose is less than a third dose implemented for exposing the first region of the energy sensitive layer when the target pattern area of the IC design layout includes the target feature without the dummy feature, and
• wherein an unexposed region of the energy sensitive layer corresponds with a background area in the target pattern area of the IC design layout.