DRY ETCHING METHOD CAPABLE OF ETCHING WITH HIGH SELECTION RATE AND METHOD OF MANUFACTURING A SEMICONDUCTOR DEVICE

摘要

PURPOSE: A dry etching method capable of etching with high selection rate and a method for manufacturing a semiconductor device are provided to obtain a high selection rate and improve the manufacturing yield or performance of a semiconductor device. CONSTITUTION: CH2F2 is used as an etching gas at the time of dry etching. When the etching gas is composed of a plurality of gases, the occupying ratio of the CH2F2 in the mixed gas is adjusted to = 20% and, when a C-containing gas is mixed in the mixed gas, the occupying ratio of the CH2F2 and C-containing gas in the mixed gas is adjusted to = 20% and that of the CH2F2 in the mixed gas is adjusted to = 5%. Consequently, etching takes place in the bottom section of a contact hole, but does not take place on a resist(31), because a resulted product of reaction accumulates on the resist(31). Therefore, the contact hole can be formed without damaging the masking property of the resist.