Embodiments described herein generally relate to a method and apparatus for plasma treating a process chamber. A substrate having a gate stack formed thereon may be placed in a process chamber, and hydrogen containing plasma may be used to treat the gate stack in order to cure the defects in the gate stack. As the result of hydrogen containing plasma treatment, the gate stack has lower leakage and improved reliability. To protect the process chamber from Hx+ ions and H* radicals generated by the hydrogen containing plasma, the process chamber may be treated with a plasma without the substrate placed therein and prior to the hydrogen containing plasma treatment. In addition, components of the process chamber that are made of a dielectric material may be coated with a ceramic coating including an yttrium containing oxide in order to protect the components from the plasma.