Charged particle beam writing method and charged particle beam writing apparatus

A charged particle beam writing apparatus that causes a deflector to deflect a charged particle beam, performs focusing using an objective lens, and writes a pattern on a substrate on a stage, the charged particle beam writing apparatus comprising:

• a discharger discharging the charged particle beam;
• a pattern density distribution calculator virtually dividing a writing region of the substrate in a mesh-like manner and calculating a pattern density distribution representing an arrangement ratio of the pattern for each mesh region;
• a dose distribution calculator calculating a dose distribution representing a dose for each mesh region using the pattern density distribution;
• an irradiation amount distribution calculator calculating an irradiation amount distribution of the charged particle beam discharged from the discharger and irradiated to the substrate using the pattern density distribution and the dose distribution;
• a fogging charged particle amount distribution calculator calculating a fogging charged particle amount distribution by convolving a distribution function for fogging charged particles with the irradiation amount distribution;
• a charge amount distribution calculator calculating a charge amount distribution due to direct charge using the pattern density distribution, the dose distribution, and the irradiation amount distribution, and calculating a charge amount distribution due to fogging charge using the fogging charged particle amount distribution;
• a position shift distribution calculator calculating, for writing positions, a first position shift of each writing position based on the charge amount distribution due to direct charge and the charge amount distribution due to fogging charge;
• a potential regulation member that is arranged at a position facing the substrate and is controlled to have a predetermined potential;
• a voltage control circuit applying a predetermined voltage to at least one of the substrate and the potential regulation member such that a potential of a surface of the substrate becomes higher than a potential of a bottom surface of the potential regulation member;
• a writer irradiating a corrected irradiation position based on the first position shift with the charged particle beam in a state where an electric field is formed;
• and
• a storage device storing the predetermined voltage as application voltage information, the predetermined voltage being obtained in advance based on a relationship between an application voltage to at least one of the substrate and the potential regulation member and a second position shift of the writing position, which is caused by a shift of a center of a low energy fogging charged particle amount distribution, so that the second position shift is smaller than a predetermined value,
• wherein the low energy fogging charged particle is a secondary charged particle generated by irradiation of the charged particle beam onto the substrate and deposited onto the substrate.