Patent ID: 8669537

Claim:
A charged particle beam writing apparatus for deflecting a charged particle beam by a main deflector and a sub deflector to write a pattern sample, comprising: a shot data generator for generating shot data from write data in which the shape and position of each graphic pattern are defined; and a deflection controller for generating deflection data for controlling the main deflector and the sub deflector from the shot data, wherein the shot data generator comprises shot dividing means for dividing the graphic pattern defined in the write data into graphics expressed in shot units, and means for distributing the respective graphics divided by the shot dividing means to subfield areas capable of being deflected by the main deflector, such that a number of shots over all subfield areas is constant regardless of a presence or absence of subfield boundaries, wherein a plurality of subfield areas are configured in such a manner that the subfield areas adjacent to one another overlap one another in widths greater than or equal to a maximum shot size, and wherein when part of each of the graphics divided by the shot dividing means is located in an overlapped portion of each of the subfield areas, the distributing means distributes the corresponding graphic to any one of the subfield areas, based on the position of a standard point of the graphic.