Methods for calculating radiation dose, methods for depicting charged particle beams, devices and programs for depicting charged particle beams

Abstract

[Problem] To improve the resolution of charged particle beam drawing while suppressing the increase in computational load. [Solution] One aspect of the present invention is an irradiation calculation method that calculates the irradiation dose of a charged particle beam used to draw a graphic pattern on a substrate according to design data at a target grid size. In this method, the drawing area for drawing the graphic pattern is hypothetically divided into a specified grid size larger than the target grid size to generate a plurality of first grid regions. The area density of the graphic pattern disposed in each first grid region is calculated. Using the area density, the first irradiation dose of an individual beam is calculated with the grid intersection of control grid points set in the drawing area as the irradiation position. Using the first irradiation dose and a conversion formula including the reduction rate relative to the target grid size, the second irradiation dose of the individual beam when the drawing area is hypothetically divided at the target grid size is obtained.

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