Focus ring and substrate processing apparatus

Abstract

A focus ring is disposed on a peripheral portion of a lower electrode that receives a substrate thereon in a process container so as to contact a member of the lower electrode. The focus ring includes a contact surface that contacts the member of the lower electrode and is made of any one of a silicon-containing material, alumina and quartz. At least one of the contact surface of the focus ring and a contact surface of the member of the lower electrode has surface roughness of 0.1 micrometers or more.

What is claimed is: 
     
         1 . A focus ring disposed on a peripheral portion of a lower electrode that receives a substrate thereon in a process container so as to contact a member of the lower electrode, the focus ring comprising:
 a contact surface that contacts the member of the lower electrode and is made of any one of a silicon-containing material, alumina and quartz,   wherein at least one of the contact surface of the focus ring and a contact surface of the member of the lower electrode has surface roughness of 0.1 micrometers or more.   
     
     
         2 . The focus ring as claimed in  claim 1 , wherein at least one of the contact surface of the focus ring and the contact surface of the member of the lower electrode has the surface roughness of 1.0 micrometers or less. 
     
     
         3 . The focus ring as claimed in  claim 1 , wherein the focus ring is integrally made of any one of the silicon-containing material, alumina and quartz. 
     
     
         4 . The focus ring as claimed in  claim 3 , wherein the focus ring is made of the silicon-containing material, and the silicon-containing material is made of a silicon single crystal or silicon carbide. 
     
     
         5 . The focus ring as claimed in  claim 1 , wherein the member of the lower electrode includes a first electrostatic attraction mechanism for a substrate and a second electrostatic mechanism for the focus ring. 
     
     
         6 . A substrate processing apparatus comprising:
 a lower electrode including an electrostatic attraction mechanism configured to electrostatically attract a substrate thereon;   a focus ring disposed on a peripheral portion of the lower electrode in a process container so as to contact the electrostatic attraction mechanism of the lower electrode; and   a radio frequency power source configured to supply radio frequency power into the process container,   wherein a contact surface of the focus ring is made of any one of a silicon-containing material, alumina and silicon carbide,   wherein at least one of the contact surface of the focus ring and a contact surface of the electrostatic attraction mechanism of the lower electrode has surface roughness of 0.1 micrometers or more.   
     
     
         7 . The substrate processing apparatus as claimed in  claim 6 , wherein the electrostatic chuck mechanism includes a first electrostatic attraction mechanism for the substrate and a second electrostatic attraction mechanism for the focus ring.