Patent ID: 9218942
Filing Date: 2015-12-22
Classification: B82Y,H01J

Abstract:
1. A charged particle beam writing apparatus comprising: a shot division unit configured to divide a figure defined in layout data into a plurality of shot figures each having a size which can be irradiated by one shot of a charged particle beam; a shot data generating unit configured to generate each shot data for each shot figure of the plurality of shot figures, where a number of times of generating the each shot data is equivalent to a number of times of multiple writing of the each shot figure of the plurality of shot figures, such that multiplicity of the multiple writing is variable per the each shot figure; a storage unit configured to store a dose map; a total dose calculation unit configured to read the dose map and calculate, for the each shot figure, a total dose used when performing the multiple writing of the each shot figure; a temporary dose calculation unit configured to calculate a temporary dose for the each shot figure per each of a number of times of multiple writing of each of a plurality of stripe areas made by virtually dividing a writing area of the target workpiece into strip-like areas each having a predetermined width, by using the total dose and the number of times of the multiple writing of the each of the plurality of stripe areas; a dose calculation unit configured to compare the calculated temporary dose with a threshold value of a dose per shot indicating a maximum dose that avoids resist heating, resist evaporation, or resist scattering, (1) and in a case the calculated temporary dose is not less than the threshold value, the calculated temporary dose is divided by the threshold value to obtain an integer rounding up from a result of the division, to calculate an actual dose per shot figure by dividing the calculated temporary dose by the integer, (2) and in a case the calculated temporary dose is less than the threshold value, to use the calculated temporary dose as the actual dose per shot figure; and a writing unit configured to perform the multiple writing of the each shot figure onto a target workpiece, in accordance with the calculated actual dose and the number of times of the each shot data generated for the each shot figure, using a charged particle beam.