Patent ID: 6930047

Claim:
An etching method using an ICP etching apparatus provided with an upper electrode and a lower electrode being opposed to said upper electrode, said lower electrode comprising at least first and second electrodes, said upper electrode comprising one coil electrode overlapping said first and second electrodes, the method comprising the steps of: disposing a substrate on said first and second electrodes in a chamber; supplying a reaction gas into said chamber under a reduce pressure; applying a first high-frequency power to said coil electrode to generate plasma; applying a second high-frequency power to said first electrode disposed below a central portion of said substrate and applying a third high-frequency power to said second electrode disposed below corner portions of said substrate to apply an AC electric field between said coil electrode and said first and second electrodes; etching a material film on said substrate disposed on said first and second electrodes, wherein said second electrode is flush with said first electrode.