Process and related device for removing by-product on semiconductor processing chamber sidewalls

A plasma processing apparatus, comprising:

• a processing chamber comprising a lower electrode arranged below an upper surface of an electrostatic chuck configured to receive a workpiece and between sidewalls of the processing chamber;
• a first radio frequency (RF) power generator electrically connected to a RF antenna;
• a sidewall voltage generator electrically connected to a sidewall electrode;
• and
• a second RF power generator electrically connected to the lower electrode.

A method for cleaning a processing chamber, the method comprising:

• connecting a switching element of a sidewall voltage generator to a first electric potential, thereby connecting a sidewall electrode to the first electric potential;
• connecting a switching element of a second radio frequency (RF) power generator to a second electric potential, thereby connecting a lower electrode to the second electric potential;
• processing a substrate comprising a first material inside a processing chamber, wherein the process generates a by-product comprising the first material that adheres to a sidewall of the processing chamber;
• removing the processed substrate from the processing chamber;
• introducing a processing gas into the processing chamber;
• switching the switching element of the second RF power generator to the first electric potential and concurrently switching the switching element of the sidewall voltage generator to a third electric potential;
• generating a cleaning plasma inside the processing chamber by connecting a first RF power generator to a RF antenna;
• and
• evacuating the processing gas and the by-product from the processing chamber.