Method and device for plasma-etching organic material film

摘要

A support electrode ( 2 ) and a counter electrode ( 16 ) constituting parallel plate electrodes are disposed in a process vessel ( 1 ). A substrate (W) with an organic material film formed thereon is supported by the support electrode ( 2 ). A high-frequency power of a frequency of 40 MHz or above for generating the plasma is applied to the support electrode ( 2 ), so that a high-frequency electric field is formed between the support electrode ( 2 ) and the counter electrode ( 16 ). A process gas is supplied into the process vessel ( 1 ) to generate plasma of the process gas by the high-frequency electric field. The organic material film on the substrate (W) is etched with the plasma, with an organic material film serving as a mask. The process gas includes an ionization accelerating gas, such as Ar, that is ionized from a ground state or metastable state with an ionization energy of 10 eV or below and has a maximum ionization cross-section of 2x10¹⁶ cm² or above.