Dose information correction method, dose information acquisition method for edge peripheral region of figure pattern, charged particle beam writing apparatus, and non-transitory computer-readable storage medium storing program

A dose information acquisition method for an edge peripheral region of a figure pattern, the dose information acquisition method comprising:

• acquiring a dose information map in which dose information related to a dose of a charged particle beam for writing a figure pattern on a target object with the charged particle beam is defined for each mesh region of a plurality of mesh regions obtained by dividing a writing region of the target object;
• setting a reference correction amount for correcting the dose information;
• calculating, for each mesh region, a gradient of the dose information defined for a mesh region by using the dose information defined for the mesh region and the dose information defined for a peripheral mesh region around the mesh region;
• calculating, for each mesh region, an individual correction amount of the dose information of the mesh region to be applied along a direction of the gradient by using a value of a calculated gradient and the reference correction amount;
• generating a corrected dose information map in which corrected dose information obtained by correcting the dose information of the mesh region using a calculated individual correction amount is defined for each mesh region;
• and
• generating and outputting an edge peripheral region dose information map in which dose information of an edge peripheral region of a figure pattern is defined for each mesh region by calculating a difference between the dose information map and the corrected dose information map.

A charged particle beam writing apparatus comprising:

• a dose information map acquisition circuit configured to acquire a dose information map in which dose information related to a dose of the charged particle beam for writing a figure pattern on a target object with the charged particle beam is defined for each mesh region of a plurality of mesh regions obtained by dividing a writing region of the target object;
• a setting circuit configured to set a reference correction amount for correcting the dose information;
• a gradient calculation circuit configured to calculate, for each mesh region, a gradient of the dose information defined for a mesh region by using the dose information defined for the mesh region and the dose information defined for a peripheral mesh region around the mesh region;
• an individual correction amount calculation circuit configured to calculate, for each mesh region, an individual correction amount of the dose information of the mesh region to be applied along a direction of the gradient using a value of a calculated gradient and the reference correction amount;
• a corrected dose information map generation circuit configured to generate a corrected dose information map in which corrected dose information obtained by correcting the dose information of the mesh region using a calculated individual correction amount is defined for each mesh region;
• and
• a writing mechanism configured to write a pattern on the target object with a charged particle beam of a dose based on the corrected dose information defined in a generated corrected dose information map.

A charged particle beam writing apparatus comprising:

• a dose information map acquisition circuit configured to acquire a dose information map in which dose information related to a dose of the charged particle beam for writing a figure pattern on a target object with the charged particle beam is defined for each mesh region of a plurality of mesh regions obtained by dividing a writing region of the target object;
• a setting circuit configured to set a reference correction amount for correcting the dose information;
• a gradient calculation circuit configured to calculate, for each mesh region, a gradient of the dose information defined for a mesh region by using the dose information defined for the mesh region and the dose information defined for a peripheral mesh region around the mesh region;
• an individual correction amount calculation circuit configured to calculate, for each mesh region, an individual correction amount of the dose information of the mesh region to be applied along a direction of the gradient using a value of a calculated gradient and the reference correction amount;
• a corrected dose information map generation circuit configured to generate a corrected dose information map in which corrected dose information obtained by correcting the dose information of the mesh region using a calculated individual correction amount is defined for each mesh region;
• an edge peripheral region dose information map generating circuit configured to generate an edge peripheral region dose information map in which dose information of an edge peripheral region of a figure pattern is defined for each mesh region by calculating a difference between the dose information map and the corrected dose information map;
• and
• a writing mechanism configured to write a pattern on the target object with a charged particle beam of a dose based on dose information corrected using the edge peripheral region dose information map.

A non-transitory computer-readable storage medium storing a program for causing a computer to execute processing comprising:

• acquiring a dose information map in which dose information related to a dose of a charged particle beam for writing a figure pattern on a target object with the charged particle beam is defined for each mesh region of a plurality of mesh regions obtained by dividing a writing region of the target object;
• setting a reference correction amount for correcting the dose information;
• calculating, for each mesh region, a gradient of the dose information defined for a mesh region by using the dose information defined for the mesh region and the dose information defined for a peripheral mesh region around the mesh region;
• storing a calculated gradient of the dose information in a storage device;
• reading the gradient of the dose information from the storage device and calculating, for each mesh region, an individual correction amount of the dose information of the mesh region to be applied along a direction of the gradient using a value of a calculated gradient and the reference correction amount;
• and
• generating and outputting a corrected dose information map in which corrected dose information obtained by correcting the dose information of the mesh region using a calculated individual correction amount is defined for each mesh region.