Atomic layer treatment process using metastable activated radical species

A substrate processing system for selectively etching a substrate, comprising:

• a first chamber;
• a second chamber including a substrate support;
• a gas delivery system to selectively supply at least one of a purge gas and a treatment gas to the first chamber and the second chamber;
• a plasma generating system to selectively generate plasma in the first chamber;
• a gas distribution device arranged between the first chamber and the second chamber, defining a plenum and including a first plurality of through holes from an upper surface of the gas distribution device to a lower surface of the gas distribution device and a second plurality of through holes from the plenum to the lower surface;
• and
• a controller configured to:
• a) flow the purge gas to purge the first chamber and the second chamber;
• b) after a), flow the treatment gas to the plenum to create an adsorption layer on a surface of the substrate;
• c) stop flow of the treatment gas;
• d) flow the purge gas to purge the first chamber and the second chamber;
• and
• e) while flowing the purge gas to the first chamber, strike plasma in the first chamber to create metastable active radical species and to deliver the metastable active radical species to the second chamber through the gas distribution device.