Plasma etching

Patent Pending PROBLEM TO BE SOLVED: To provide a high-performance plasma etching method required for working etc. of MEMS devices, semiconductor devices, etc. ; SOLUTION: The plasma etching method supplies treatment gas 1, containing fluorine gas (F<SB>2</SB>), to plasma generating chamber 2, alternately repeats application of high-frequency electric field and stopping of the application to generate a plasma 5, and irradiates a substrate 9 with the plasma 5 to perform substrate treatment.