Higher pressure purge for impurity reduction in radical treatment chamber

A method of post-deposition processing, comprising:

• performing a preheat process in a radical treatment chamber, the preheat process comprising exposing a substrate having a metal layer formed thereon to purge gas and purging the purge gas at a pressure of between 500 Torr and 535 Torr;
• subsequent to the preheat process, performing a radical treatment process in the radical treatment chamber, the radical treatment process comprising exposing the substrate to radical species;
• and
• subsequent to the radical treatment process, performing a thermal anneal process in the radical treatment chamber, the thermal anneal process comprising exposing the substrate to the purge gas and purging the purge gas at a pressure of between 400 Torr and 535 Torr.