PLASMA ETCHING METHOD

PURPOSE:To inhibit the temperature rise of a substrate to be processed to predetermined value or less, and to enable etching in high power density by intermittently applying high-frequency power to a parallel plate type electrode and etching the substrate by plasma. CONSTITUTION:A dummy is fixed onto a target electrode first, high frequency power is applied under predetermined conditions, and the application is stopped at the cloudy point of a positive resist, a prescribed time is obtained, and time for which the substrate is cooled up to a predetermined temperature is acquired. Accordingly, power applying time is shortened while using the degenerating point of the resist as a reference, the temperature of the substrate to be processed is regulated, the process is repeated according to a prescribed manner by using the dummy, and an etching profile until n times in actual processing is prepared. High-frequency power is applied intermittently according to the etching profile prepared, the substrate is etched and the temperature rise of the substrate is prevented in actual plasma etching. Accordingly, the deformation and degeneration of a resist mask are prevented, and the yield of a device with a minute pattern can be improved.