Patent ID: 6929985

Claim:
A method of manufacturing a semiconductor device, comprising: (a) a first step for forming a gate oxide film on a semiconductor substrate; (b) a second step for handling the semiconductor substrate after the first step in filtered air from an air filter in a clean room including a step of providing said air filter which comprises a filter medium, a frame which contains the filter medium and a sealing material that firmly seals the frame and the filter medium, and the filter medium releasing gaseous organic substances in an amount of 10 μg or less per 1 g of its sample when heated at 150° C. for 30 min by a purge & trap method, the sealing material releasing gaseous organic substances in an amount of 50 μg or less per 1 g of its sample when heated at 150° C. for 30 min by a purge & trap method is attached to a support frame of a ceiling of the clean room constituting an opening in the presence of a gasket between the air filter and the support frame, the gasket releasing gaseous organic substances in an amount of 50 μg or less per 1 g of its sample when heated at 150° C. for 30 min by a purge & trap method; and (c) a third step for forming a gate electrode on the gate oxide film.