Patent ID: 8003484

Claim:
A method for forming a silicon oxide film, comprising: a first oxidation step for generating plasma of a processing gas, under a first process condition that a ratio of oxygen in the processing gas is 1% or less and pressure is within a range of 0.133 to 133 Pa, in a processing chamber of a plasma processing apparatus, so as to form the silicon oxide film, by oxidizing silicon on a surface of an object to be processed including silicon as a main component, by using the plasma; and a second oxidation step, performed following the first oxidation step, for generating plasma of processing gas, under a second process condition that the ratio of oxygen in the processing gas is 20% or more and pressure is within a range of 400 to 1333 Pa, so as to form an additional silicon oxide film, by further oxidizing the surface of the object to be processed, by using the plasma, thereby improving quality of the silicon oxide film, wherein the plasma in the first and second oxidation steps is microwave excitation plasma generated from the processing gas, with a microwave introduced into the processing chamber from a planar antenna having a plurality of slots formed therein.