Plasma processing method

Abstract

A plasma processing method includes removing a deposit, which adheres to a member within a processing vessel and includes at least one of a transition metal and a base metal, by plasma of a processing gas, wherein the processing gas includes Ar gas and a CH z F w gas, and does not includes a chlorine-based gas and a nitrogen-based gas. The deposit is removed by the plasma of the processing gas while applying a negative DC voltage to the member within the processing vessel, and the negative DC voltage is set to be equal to or less than −100V such that argon ions in the plasma of the processing gas collide with the member within the processing vessel and the deposit is removed by sputtering of the argon ions.

We claim: 
     
         1 . A plasma processing method comprising:
 removing a deposit, which adheres to a member within a processing vessel and includes at least one of a transition metal and a base metal, by plasma of a processing gas, wherein the processing gas includes Ar gas and a CH z F w  gas, in which z is an integer equal to or less than 3 and w is also an integer equal to or less than 3, and does not includes a chlorine-based gas and a nitrogen-based gas,   wherein the deposit is removed by the plasma of the processing gas while applying a negative DC voltage to the member within the processing vessel, and   the negative DC voltage is set to be equal to or less than −100V such that argon ions in the plasma of the processing gas collide with the member within the processing vessel and the deposit is removed by sputtering of the argon ions.   
     
     
         2 . The plasma processing method of  claim 1 ,
 wherein the processing gas is at least one of a CHF 3 /Ar/O 2  gas, a CH 2 F 2 /Ar/O 2  gas and a CH 3 F/Ar/O 2  gas.   
     
     
         3 . The plasma processing method of  claim 1 ,
 wherein the transition metal is at least one of Ti, Hf and Ta.   
     
     
         4 . The plasma processing method of  claim 1 ,
 wherein the base metal is Al.