Methods and apparatus for processing a substrate

A method for cleaning a process kit disposed in an inner volume of a processing chamber, comprising:

• energizing a cleaning gas disposed in the inner volume of the processing chamber to create a plasma;
• and
• controlling an auto capacitor tuner (ACT), connected to ground and to a sputtering target disposed in the inner volume, using a controller configured to tune the ACT to maintain a predetermined potential difference between the plasma in the inner volume and a process kit during an etch process to remove sputtering material from the process kit, wherein the predetermined potential difference is based on a resonant point of the ACT, wherein the process kit comprises a shield and wherein the resonant point is about 58% to about 75% of total tuning capacitance such that the controller is configured to control the etch process so that an edge of the shield at a rate of about 11.7 Å/s, a top of the shield at a rate of about 11.5 Å/s, and a corner of the shield at a rate of about 12 Å/s.

A non-transitory computer readable storage medium having stored thereon instructions that when executed by a processor perform a method for cleaning a process kit disposed in an inner volume of a processing chamber, comprising:

• energizing a cleaning gas disposed in the inner volume of the processing chamber to create a plasma;
• and
• controlling an auto capacitor tuner (ACT), connected to ground and to a sputtering target disposed in the inner volume, using a controller configured to tune the ACT to maintain a predetermined potential difference between the plasma in the inner volume and a process kit during an etch process to remove sputtering material from the process kit, wherein the predetermined potential difference is based on a resonant point of the ACT, wherein the process kit comprises a shield and wherein the resonant point is about 58% to about 75% of total tuning capacitance such that the controller is configured to control the etch process so that an edge of the shield at a rate of about 11.7 Å/s, a top of the shield at a rate of about 11.5 Å/s, and a corner of the shield at a rate of about 12 Å/s.