Patent ID: 8759799

Claim:
A charged particle beam writing apparatus comprising: a dose coefficient calculation unit configured to calculate an n-th dose correction coefficient in iterative calculation of a charged particle beam to be shot in a small region concerned by the iterative calculation, for each small region of a plurality of small regions made by virtually dividing a writing region of a target object into mesh-like regions; a change rate calculation unit configured to calculate, for the each small region, a rate of change from an (n-1)th dose correction coefficient to the n-th dose correction coefficient calculated in the iterative calculation, as an n-th change rate; a correction calculation unit configured to correct, for the each small region, the n-th dose correction coefficient by using the n-th change rate; a dose calculation unit configured to calculate, for the each small region, a dose of a charged particle beam to be shot in a small region concerned by using the n-th dose correction coefficient corrected; and a writing unit configured to write a desired pattern in the small region concerned by using the dose calculated.