A manufacturing method of a semiconductor device using a semiconductor manufacturing unit comprising a reaction chamber, a substrate mounting stage, and a high frequency power supply coupled to the substrate mounting stage, a blocking capacitor interposed between the substrate mounting stage and the high-frequency power supply to continuously perform a plurality of dry etching processing with respect to the same substrate in the same reaction chamber, the method includes: disposing a substrate on a substrate mounting stage, and applying high-frequency powers to the substrate mounting stage while introducing a fluorocarbon-based first gas to perform a first dry etching processing with respect to the substrate, the substrate including an organic material film and a silicon compound film sequentially deposited on a surface thereof and a resist film patterned on the silicon compound film, the first dry etching processing including processing the silicon compound film with the resist film being used as a mask; and stopping application of one of the high-frequency powers, thereby reducing a bias voltage generated to the substrate while introducing a second gas after the first dry etching processing to remove a fluorocarbon-based deposition in the reaction chamber and perform a second dry etching processing with respect to the substrate.