Method of oxidizing member to be treated
A method for oxidation of an object to be processed is provided wherein an oxide film can provide favorable film quality and a laminate structure of nitride film and oxide film can be obtained by a thermal oxidation of a nitride film. In a method for oxidation of a surface of an object to be processed in a single processing container 8 which can contain a plurality of objects to be processed, at least a nitride film is exposed on said surface, and said oxidation is performed by mainly using active hydroxyl/oxygen species in a vacuum atmosphere, setting a processing pressure to 133 Pa or below, and setting a processing temperature to 400° C. or above. Under these conditions, high interplanar uniformity is maintained and oxide films with favorable film quality are obtained by oxidizing nitride films on the surfaces of a plurality of objects to be processed.
1. A method for oxidation of a surface of an object to be processed in a single processing container which can contain a plurality of objects to be processed, said method characterized by performing said oxidation wherein:
an oxidizing gas and H 2 gas are fed into said processing container, respectively, by separate gas feed locations, a distance between a region for accommodating the object to be processed in the processing container and each of said gas feed locations being 100 mm or more;
active hydroxyl species and active oxygen species are mainly used in a vacuum atmosphere;
a processing pressure is determined to be 133 Pa or below;
a processing temperature is determined to be 400° C. or above; and
H 2 concentration inside said processing container is within the range of from 5 to 33%;
further wherein a plurality of stack-like silicon-layer projections are formed on a surface of said object to be processed, and a silicon nitride film is formed on upper surfaces of said projections.
2. A method for oxidation of an object to be processed according to claim 1 , characterized in that: said oxidizing gas includes one or more gases selected from the group consisting of O 2 , N 2 O, NO and NO 2 .
3. A method for oxidation of an object to be processed according to claim 1 , characterized in that said processing temperature is within the range from 800 to 1,000° C.
4. A method for oxidation of an object to be processed according to claim 1 , wherein said oxidation forms SiO 2 on said silicon nitride film of the object.