Patent ID: 8122390

Claim:
A charged particle beam writing apparatus comprising: a first area density calculation unit configured to calculate a first area density occupied by a pattern of a first dimension in a predetermined region; a first dimension error calculation unit configured to calculate a first dimension error caused by a loading effect, using the first area density; a first dimension calculation unit configured to calculate a second dimension of a pattern obtained by correcting the first dimension error of the first dimension; a second area density calculation unit configured to calculate a second area density occupied by the pattern of the second dimension in the predetermined region; a second dimension error calculation unit configured to calculate a second dimension error caused by the loading effect, using the second area density; a second dimension calculation unit configured to calculate a third dimension by adding the second dimension error to the second dimension; a judgment unit configured to judge whether a difference between the first dimension and the third dimension is within a predetermined range or not; and a writing unit configured to write the pattern of the second dimension in which the difference is within the predetermined range, onto a target workpiece by using a charged particle beam.