Pattern writing and forming method

A pattern forming method comprising:

• storing pattern data for writing patterns, the pattern data including a reference radiation amount D0 for radiating an energy beam on a resist-applied target, a distribution of a pattern dependency of a pattern-size variation Δ due to a loading effect, and an energy distribution “s” applied to the resist by the energy beam;
• dividing writing regions of the target into grids to provide sub-writing regions in the grids;
• obtaining a distribution of a pattern-area density per sub-writing region based on the pattern data;
• calculating a radiation amount DCf(x) for correcting a long-range fogging exposure in each sub-writing region based on the pattern-area density and the reference radiation amount D0;
• calculating a radiation amount DCp(x) for correcting a proximity effect applied to those of the patterns in each sub-writing region based on the pattern data and the reference radiation amount D0;
• calculating a radiation amount D(x) based on the radiation amount DCf(x), the radiation amount DCp(x), the distribution of a pattern dependency, and the energy distribution “s”;
• deciding radiation locations and radiation shapes of the energy beam based on data on pattern locations and pattern shapes of the patterns in the sub-writing regions and radiating the energy beam on the radiation locations on the target with the radiation shapes for a period in which a radiated energy level from the energy beam reaches the radiation amount D(x), thus writing the patterns on the resist;
• developing the pattern-written resist to form a resist pattern;
• and
• etching the target with the resist pattern as a mask, thus forming the patterns on the target.