Method of treating substrate

A method of treating a substrate by using a substrate treating apparatus generating plasma in a treatment space by applying microwaves, the method comprising:

• a plasma treatment operation of treating the substrate with the plasma;
• a replacement operation in which the plasma treatment operation is performed a preset number of times and a component included in the substrate treating apparatus is replaced;
• and
• a backup operation of backing up the substrate treating apparatus after the replacement operation,
• wherein the backup operation includes a bake purge operation for removing byproducts present in the component, a primary purge operation of performing a primary purge of the treatment space after the bake purge operation, and a secondary purge operation of performing a secondary purge of the treatment space after the primary purge operation,
• in the bake purge operation, atmosphere of the treatment space is formed to atmospheric pressure and a temperature of the treatment space is formed to 100 degrees Celsius to 200 degrees Celsius,
• in the primary purge operation, first purge gas is supplied to the treatment space formed at room temperature to check a leak in the treatment space, and the first purge gas supplied to the treatment space is exhausted to primarily purge the treatment space, and
• in the secondary purge operation, second purge gas is supplied to the treatment space formed at a temperature higher than the room temperature by increasing the temperature of the treatment space to check the leak in the treatment space, and the second purge gas supplied to the treatment space is exhausted to secondarily purge the treatment space.