| 摘要 |
PROBLEM TO BE SOLVED: To reduce irregularities on surfaces, when a silicon oxide film and a polysilicon film are etched simultaneously. SOLUTION: A process gas comprising mixed gases, including at least a CHF3 gas and a CF4 gas, is introduced into an airtight processing chamber. The flow rate of the CHF3 gas in relation to the CF4 gas in the processing gas is controlled so that the etching selection ratio of a silicon oxide film 260 and a polysilicon film 240 becomes a value close to 1. Consequently, a silicon oxide film portion and a polysilicon film portion on a treated substrate are etched at substantially equal rates. COPYRIGHT: (C)2003,JPO
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