Substrate support assembly, plasma processing apparatus, and plasma processing method

Abstract

A substrate support assembly includes a supporting table and one or more piezoelectric elements disposed between the supporting table and a focus ring. The supporting table has an upper surface, and the upper surface includes a first region on which a substrate is mounted and a second region on which the focus ring is disposed, the second region extending in a circumferential direction at an outer side of the first region. The one or more piezoelectric elements are disposed between the focus ring and the second region to be in direct or indirect contact with the focus ring and the second region. Changes in thicknesses of the one or more piezoelectric elements cause a change in a vertical position of the focus, and the thicknesses of the one or more piezoelectric elements are adjustable to suppress a generation of a gap between the focus ring and the second region.

1 . A substrate support for use in a plasma processing apparatus, the substrate support comprising:
 a support having a substrate supporting region;   a ring disposed so as to surround a substrate on the substrate supporting region of the support;   an annular piezoelectric device disposed below the ring; and   an annular member disposed between the ring and the annular piezoelectric device, the annular member having a different function from the annular piezoelectric device.   
     
     
         2 . The substrate support of  claim 1 , wherein the annular member is an electrostatic chuck. 
     
     
         3 . The substrate support of  claim 1 , wherein the annular member is a heat transfer sheet. 
     
     
         4 . The substrate support of  claim 1 , wherein the annular member has an upper surface in contact with the ring. 
     
     
         5 . The substrate support of  claim 4 , wherein the annular member has a lower surface in contact with the annular piezoelectric device. 
     
     
         6 . The substrate support of  claim 1 , wherein the support has a ring supporting region, the annular piezoelectric device is disposed on the ring supporting region. 
     
     
         7 . The substrate support of  claim 6 , wherein the support includes an electrostatic chuck, the electrostatic chuck has the substrate supporting region. 
     
     
         8 . The substrate support of  claim 7 , wherein the electrostatic chuck has the ring supporting region. 
     
     
         9 . The substrate support of  claim 1 , wherein the annular piezoelectric device has a plurality of piezoelectric segments. 
     
     
         10 . The substrate support of  claim 9 , wherein the ring has a first ring segment and a second ring segment,
 the plurality of piezoelectric segments includes a first annular piezoelectric segment disposed below the first ring segment, and a second annular piezoelectric segment disposed below the second ring segment.   
     
     
         11 . The substrate support of  claim 9 , wherein the plurality of piezoelectric segments are coaxially disposed. 
     
     
         12 . The substrate support of  claim 9 , wherein the plurality of piezoelectric segments are arranged in a circumferential direction. 
     
     
         13 . A plasma processing apparatus comprising:
 a plasma processing chamber;   a substrate support disposed in the plasma processing chamber, the substrate support including:
 a support having a substrate supporting region, the support including an electrode; 
 a ring disposed so as to surround a substrate on the substrate supporting region of the support; 
 an annular piezoelectric device disposed below the ring; and 
 an annular member disposed between the ring and the annular piezoelectric device, the annular member having a different function from the annular piezoelectric device; 
 at least one RF power supply electrically connected to the electrode; and 
   at least one DC power supply electrically connected to the annular piezoelectric device.   
     
     
         14 . The plasma processing apparatus of  claim 16 , wherein the annular piezoelectric device includes a body, a plurality of first electrode layers and a plurality of second electrode layers,
 the plurality of first electrode layers and the plurality of second electrode layers are disposed in the body and alternately arranged in a vertical direction,   the plurality of first electrode layers are electrically connected to one another, and   the plurality of second electrode layers are electrically connected to one another.   
     
     
         15 . The plasma processing apparatus of  claim 14 , wherein the body is made of a dielectric elastomer. 
     
     
         16 . The plasma processing apparatus of  claim 15 , wherein the annular piezoelectric device includes a corrosion-resistant resin covering a surface of the body. 
     
     
         17 . The plasma processing apparatus of  claim 14 , wherein the at least one DC power supply includes a first DC power supply and a second DC power supply,
 the first DC power supply is electrically connected to the plurality of first electrode layers,   the second DC power supply is electrically connected to the plurality of second electrode layers.   
     
     
         18 . The plasma processing apparatus of  claim 17 , further comprising:
 a first RF filter electrically connected between the first DC power supply and the plurality of first electrode layers; and   a second RF filter electrically connected between the second DC power supply and the plurality of second electrode layers.   
     
     
         19 . The plasma processing apparatus of  claim 13 , further comprising:
 a RF filter electrically connected between the annular piezoelectric device and the at least one DC power supply.