Charged particle beam writing method and charged particle beam writing apparatus

A charged particle beam writing apparatus that writes a pattern on a substrate using a charged particle beam in an irradiation amount to correct a proximity effect and a middle range effect having an influence radius shorter than an influence radius of the proximity effect, the charged particle beam writing apparatus comprising:

• a mesh division unit virtually dividing a writing region of the substrate into a plurality of first mesh regions in a first mesh size;
• an area density calculation unit that calculates an area density of the pattern for each of the plurality of first mesh regions to generate first mesh data;
• a first mesh conversion unit converting a mesh size of the first mesh data into a second mesh size greater than the first mesh size to generate second mesh data;
• a first convolution operation unit performing a convolution operation between the second mesh data and a proximity effect correction kernel to generate third mesh data;
• a second mesh conversion unit converting a mesh size of the third mesh data into the first mesh size to generate fourth mesh data;
• a second convolution operation unit performing a convolution operation between the first mesh data and a middle range effect correction kernel to generate fifth mesh data;
• an addition unit adding the fourth mesh data and the fifth mesh data together to calculate an irradiation amount of the charged particle beam for each of the plurality of first mesh regions;
• and
• a writer writing the pattern on the substrate using the charged particle beam in the calculated irradiation amount.