Etching chamber having flow equalizer and lower liner

Abstract

A plasma processing chamber having a lowered flow equalizer and a lower chamber liner. In an etching process, the processing gases may be unevenly drawn from the processing chamber which may cause an uneven etching of the substrate. By equalizing the flow of the processing gases evacuated from the chamber, a more uniform etching may occur. By electrically coupling the flow equalizer to the chamber liners, the RF return path from the flow equalizer may run along the chamber liners and hence, reduce the amount of plasma drawn below the substrate during processing.

1 . A plasma apparatus, comprising:
 a chamber body;   a first chamber liner disposed within said chamber body;   a second chamber liner disposed within said chamber body below said first chamber liner; and   a flow equalizer disposed within said chamber body and coupled to both the first chamber liner and the second chamber liner.   
   
   
       2 . The apparatus of  claim 1 , wherein the flow equalizer comprises aluminum. 
   
   
       3 . The apparatus of  claim 1 , further comprising a countersunk fastening mechanism coupling the second chamber liner to a bottom of the chamber body. 
   
   
       4 . The apparatus of  claim 1 , wherein the second chamber liner is disposed in the chamber body such that a plenum is present between the second chamber liner and the chamber body. 
   
   
       5 . The apparatus of  claim 4 , wherein the second chamber liner is disposed in the chamber body such that a plenum is present between the second chamber liner and a bottom of the chamber body. 
   
   
       6 . The apparatus of  claim 1 , wherein the flow equalizer has an opening therethrough, wherein the center of the opening is offset from the center of the flow equalizer. 
   
   
       7 . The apparatus of  claim 1 , wherein the flow equalizer extends below a location wherein the first chamber liner, the second chamber liner, and the flow equalizer are coupled together. 
   
   
       8 . The apparatus of  claim 1 , wherein the apparatus is an etching apparatus. 
   
   
       9 . The apparatus of  claim 1 , wherein the second chamber liner comprises nickel. 
   
   
       10 . An etching apparatus, comprising:
 a chamber body;   a substrate support pedestal disposed in the chamber body;   a gas introduction showerhead disposed in the chamber opposite to the substrate support;   a first chamber liner disposed in the chamber body such that the substrate support pedestal, the gas introduction showerhead, and the first chamber liner at least partially enclose a processing area;   an annular baffle coupled to the substrate support pedestal and at least partially surrounding the substrate support pedestal;   a second chamber liner coupled to the chamber body and disposed below the first chamber liner; and   a flow equalizer disposed below the baffle and coupled to both the first chamber liner and the second chamber liner.   
   
   
       11 . The apparatus of  claim 10 , wherein the flow equalizer extends radially inward from the chamber body. 
   
   
       12 . The apparatus of  claim 10 , wherein the first chamber liner has a first annular notch cut into the bottom surface, the second chamber liner comprises a second annular notch cut into the bottom surface, a first electrically conductive ring is disposed within the first notch and a second electrically conductive ring is disposed within the second notch, and the flow equalizer is coupled to the first ring and the second ring. 
   
   
       13 . The apparatus of  claim 10 , wherein the flow equalizer comprises aluminum. 
   
   
       14 . The apparatus of  claim 10 , wherein the flow equalizer has an opening therethrough, wherein the center of the opening is offset from the center of the flow equalizer. 
   
   
       15 . The apparatus of  claim 14 , wherein the diameter of the opening is less than the width of the baffle. 
   
   
       16 . The apparatus of  claim 10 , wherein a distance between the flow equalizer and the pedestal gradually increases from a first point to a second point disposed 180 degrees radially from the first point. 
   
   
       17 . The apparatus of  claim 16 , wherein the first point is closer to a vacuum evacuation port than the second point. 
   
   
       18 . The apparatus of  claim 10 , further comprising a countersunk fastening mechanism coupling the second chamber liner to a bottom of the chamber body. 
   
   
       19 . The apparatus of  claim 10 , wherein the second chamber liner comprises a bottom surface comprising nickel. 
   
   
       20 . An etching apparatus, comprising:
 a chamber body;   a substrate support pedestal disposed in the chamber body;   a gas introduction showerhead disposed in the chamber opposite to the substrate support;   a first chamber liner disposed in the chamber body such that the substrate support pedestal, the gas introduction showerhead, and the first chamber liner at least partially enclose a processing area, wherein the first chamber liner has a first annular notch cut into the bottom surface and a first electrically conductive ring is disposed within the first annular notch;   an annular baffle coupled to the substrate support pedestal and at least partially surrounding the substrate support pedestal;   a second chamber liner coupled to the chamber body and disposed below the first chamber liner, wherein the second chamber liner has a second annular notch cut into the bottom surface and a second electrically conductive ring is disposed within the second annular notch; and   a flow equalizer extending radially inward from the chamber body and disposed below the baffle and coupled to both the first chamber liner and the second chamber liner, wherein the flow equalizer is coupled to the first annular ring and the second annular ring, wherein the flow equalizer has an opening therethrough, wherein the center of the opening is offset from the center of the flow equalizer, and wherein a width of the flow equalizer gradually decreases from a first point to a second point disposed 180 degrees radially from the first point.