Multi-charged particle beam writing apparatus, and multi-charged particle beam writing method

A multi-charged particle beam writing apparatus comprising:

• a shot data generation circuit, provided relating to a first beam array of charged particle beams implemented to be emittable by a multiple beam irradiation mechanism, configured to generate shot data for a second beam array whose number of beams is smaller than that of the first beam array implemented;
• a transfer circuit configured to transfer, in order of shot, the shot data for the second beam array whose number of beams is smaller than that of the first beam array implemented;
• a plurality of registers, each arranged for a corresponding beam of the first beam array, each configured to store shot data of the corresponding beam;
• and
• a writing mechanism that includes the multiple beam irradiation mechanism, configured to write a pattern on a target object by performing shots of the second beam array,
• wherein each register of registers, in the plurality of registers, for the second beam array stores shot data for an n-th shot of the second beam array, and simultaneously, each register of registers, in the plurality of registers, for a third beam array, which is other than the second beam array in the first beam array, stores at least a part of shot data for an (n+1)th shot of the second beam array, and in a case of the n-th shot having been completed, the shot data for the (n+1)th shot is shifted at least from the each register for the third beam array to the each register for the second beam array.