Plasma processing apparatus and method

A plasma processing apparatus includes in a processing chamber, a sample stage, a bell jar, a coil antenna, a Faraday shield, and a gas ring member located below a skirt portion of the bell jar and above the sample stage. The gas ring member supplies a process gas to a plasma generating space inside the bell jar from a gas port disposed on an inner surface of the gas ring member. A ring shaped plate is disposed near a periphery of the Faraday shield and having an inner surface facing and covering along the inner surface of the gas ring member and being spaced from the inner surface of the gas ring member so as to delimit a gap therebetween.