Pattern forming method and heating apparatus

A heating apparatus for heating a substrate, comprising:

• a mounting table which is disposed in a container and on which the substrate, on which a film of a block copolymer is to be formed, is mounted;
• a heating unit which is embedded in the mounting table and heats the substrate mounted on the mounting table;
• a solvent vapor supply unit which supplies gas containing vapor of a solvent into the container;
• an ejection unit which ejects the gas in the container;
• and
• a control unit configured to
• control the solvent vapor supply unit, the ejection unit, and the heating unit to heat the film of the block copolymer containing at least two polymers in the container under a solvent vapor atmosphere to subject the block copolymer to phase separation,
• wherein, in the phase separation, a partial pressure of a solvent vapor in the solvent vapor atmosphere is decreased continuously or stepwise,
• wherein, in the phase separation, early phase separation is obtained by control that increases fluidity of the polymers during an initial stage, and decreases the fluidity after the polymers gather together to array the polymers in a predetermined pattern.