Atomic oxygen detection in semiconductor processing chambers

A semiconductor processing chamber comprising:

• a chamber body defining a substrate processing region;
• a gas inlet in the chamber body to supply gas to the substrate processing region, and a gas outlet in the chamber body to remove gas effluents from the substrate processing region;
• and
• an atomic oxygen sensor positioned within the substrate processing region between the gas inlet and the gas outlet.

A semiconductor processing method comprising:

• flowing an oxygen-containing gas into a substrate processing region of a semiconductor processing chamber;
• detecting a concentration of atomic oxygen in the substrate processing region with an atomic oxygen sensor positioned in the semiconductor processing chamber, wherein the atomic oxygen sensor includes at least one electrode comprising a material selectively permeable to atomic oxygen over molecular oxygen, and includes a solid electrolyte that selectively conducts atomic oxygen ions;
• and
• adjusting the flow of the oxygen-containing gas into the semiconductor processing chamber based on the concentration of atomic oxygen detected by the atomic oxygen sensor.