Patent ID: 7578889

Claim:
A method for cleaning an electrode assembly for generating plasma in a plasma chamber comprising a plasma-exposed silicon surface, the method comprising: pre-cleaning with a nitric acid solution an inner liner of a bath and a component used to suspend the electrode assembly in the bath, wherein the nitric acid solution comprises less than 10% nitric acid; suspending the electrode assembly within the pre-cleaned inner liner of the bath using the pre-cleaned component; soaking the electrode assembly in or cleaning the electrode assembly with ultra-pure water contained within the pre-cleaned inner liner of the bath; removing the electrode assembly from the pre-cleaned inner liner of the bath; and removing contaminants from the silicon surface of the electrode assembly by contacting the silicon surface with an acidic solution comprising hydrofluoric acid, nitric acid, acetic acid, and water, wherein the electrode assembly comprises a showerhead electrode having a plurality of gas outlets.