Substrate treating method and apparatus used therefor

A substrate treating method for performing a heat treatment of a substrate having a treated film formed thereon in a heat treating space of a heat treating chamber, the substrate treating method comprising:

• an exhaust step of only performing exhausting of gas within the heat treating space without supplying inert gas into the heat treating space, wherein the heat treating space is formed by a cover enclosing surroundings of a heat treating plate;
• an inert gas supply step of supplying inert gas from an upper portion of the heat treating space into the heat treating space, after completion of the exhaust step, and supplying inert gas into a gap between an outer peripheral surface of the heat treating plate and an inner wall of the cover;
• and
• a heat treating step of performing the heat treatment of the substrate in the heat treating space,
• the heat treating step being performed after the exhaust step and the inert gas supply step,
• wherein the heat treating plate has through holes therein, and the cover has an exhaust port therein, and
• the heat treating step is performed while performing exhaust only from the through holes in the heat treating plate, and not from the exhaust port of the cover.