To prevent a gate insulation film from being damaged when a semiconductor device is manufactured by controlling either rf signal, power, magnetic field, pressure, or gas speed so that the electron energy distribution in the plasma can be made smaller than a specific value and enabling electrons to enter a conductor pattern between high-aspect-ratio insulator patterns.
An etching gas is introduced from a gas introduction port 2 and is exhaust from an exhaust port 3 and then an etching gas atmosphere with a specific pressure is formed within a plasma generation room 4. While generating magnetic field by a main coil 7, microwave is introduced into the plasma generation room 4 from a microwave waveguide pipe 5, thus generating ECR plasma in the plasma generation room 4. Then, at least either one of rf frequency, power, magnetic field, pressure, and gas seed is controlled so that electron energy distribution in plasma or an electron temperature which is the representative value becomes smaller than a predetermined value, thus enabling an electron to enter a conductor pattern between high-aspect-ratio insulator patterns.
KAMATA TAKESHI
HIKOSAKA YUKINOBU
HASEGAWA AKIHIRO