Method of making a gas distribution member for a plasma processing chamber

Abstract

A method of making a Si containing gas distribution member for a semiconductor plasma processing chamber comprises forming a carbon member into an internal cavity structure of the Si containing gas distribution member. The method includes depositing Si containing material on the formed carbon member such that the Si containing material forms a shell around the formed carbon member. The Si containing shell is machined into the structure of the Si containing gas distribution member wherein the machining forms gas inlet and outlet holes exposing a portion of the formed carbon member in an interior region of the Si containing gas distribution member. The method includes removing the formed carbon member from the interior region of the Si containing gas distribution member with a gas that reacts with carbon, dissociating the carbon atoms, which may thereby be removed from the interior region of the Si containing gas distribution member leaving a shaped internal cavity in the interior region of the Si containing gas distribution member.

What is claimed is: 
     
         1 . A showerhead electrode assembly for a semiconductor plasma processing chamber comprising a Si containing gas distribution member made by forming a carbon member into a form corresponding to an internal cavity structure of the Si containing gas distribution member; depositing a Si containing material on the formed carbon member such that the Si containing material forms a shell of a predetermined thickness around the formed carbon member; machining the Si containing shell into the structure of the Si containing gas distribution member wherein the machining forms gas inlet and outlet holes exposing a portion of the formed carbon member in an interior region of the Si containing gas distribution member; and removing the formed carbon member from the interior region of the Si containing gas distribution member with a gas that reacts with carbon, dissociating the carbon atoms, which may thereby be removed from the interior region of the Si containing gas distribution member leaving a shaped internal cavity in the interior region of the Si containing gas distribution member; and a silicon showerhead electrode wherein the Si containing gas distribution member has a pattern of gas holes matching a pattern of gas holes of the silicon showerhead electrode. 
     
     
         2 . The showerhead electrode assembly of  claim 1 , wherein the Si containing gas distribution member is a gas distribution plate, thermal control plate, or a backing plate. 
     
     
         3 . A method of processing a semiconductor substrate in a plasma processing chamber including the showerhead electrode assembly of  claim 1 , the method comprising:
 transporting a semiconductor substrate into the plasma processing apparatus and supporting the substrate on a substrate support;   introducing a process gas into the plasma processing chamber through the Si containing gas distribution member;   energizing the process gas into a plasma state; and   processing the semiconductor substrate with the plasma.   
     
     
         4 . The method of  claim 3 , wherein the processing includes deposition of conductive or dielectric material on the substrate. 
     
     
         5 . The method of  claim 3 , wherein the processing includes plasma etching a layer on the substrate wherein the layer is metal, dielectric, or photoresist. 
     
     
         6 . The method of  claim 5 , wherein the plasma etching comprises etching openings in a dielectric material using fluorocarbon and/or hydrofluorocarbon etching gas. 
     
     
         7 . The showerhead electrode assembly of  claim 1 , wherein the method includes depositing Si containing material on the formed carbon member includes supporting the formed carbon member on a first side of the formed carbon member and depositing Si containing material on a second side of the formed carbon member, turning the formed carbon member, and then supporting the deposited Si containing material on the second side of the formed carbon member and depositing Si containing material on the first side of the formed carbon member. 
     
     
         8 . The showerhead electrode assembly of  claim 1 , wherein the formed carbon member comprises multiple disconnected carbon elements which are formed and arranged in a spatial relationship corresponding to the internal cavity structure of the Si containing gas distribution member, the multiple disconnected carbon elements being arranged such that they may form more than one fluidly isolated gas zones in the Si containing gas distribution member wherein depositing Si containing material on the formed and arranged carbon elements comprises supporting each carbon element on a first side and depositing Si containing material on each second side of the formed and arranged carbon elements forming a portion of the Si containing shell on the second sides of the formed and arranged carbon elements, turning the formed and arranged carbon elements, and then supporting the portion of the Si containing shell on the second sides of the formed and arranged carbon elements and depositing Si containing material on each first side of the formed and arranged carbon elements forming the Si containing shell on the formed and arranged carbon elements. 
     
     
         9 . The showerhead electrode assembly of  claim 8 , wherein the fluidly isolated gas zones inside of the Si containing gas distribution member are arranged such that each fluidly isolated gas zone may allow a different radial or annular distribution of process gases. 
     
     
         10 . The showerhead electrode assembly of  claim 8 , wherein two disconnected carbon elements are formed into the corresponding form of an internal cavity having two fluidly isolated gas plenums inside of the Si containing gas distribution member. 
     
     
         11 . The showerhead electrode assembly of  claim 1 , wherein the Si containing material depositing step is performed by a CVD process, a PECVD process, or a cold spray process. 
     
     
         12 . The showerhead electrode assembly of  claim 1 , wherein the removal of the formed carbon member comprises an aching process. 
     
     
         13 . The showerhead electrode assembly of  claim 1 , wherein the removal of the formed carbon member comprises heating the Si containing coated carbon member in an oxygen-containing atmosphere to remove the carbon from the interior region of the Si containing gas distribution member. 
     
     
         14 . The showerhead electrode assembly of  claim 1 , wherein the removal of the carbon member comprises heating the Si containing coated carbon member in a hydrogen-containing atmosphere to remove the carbon from the interior region of the Si containing gas distribution member. 
     
     
         15 . The showerhead electrode assembly of  claim 1 , wherein each gas inlet and outlet hole is fabricated by a mechanical fabrication technique such as drilling. 
     
     
         16 . The showerhead electrode assembly of  claim 15 , wherein each gas inlet and outlet hole is further laser drilled to adjust the permeability of each gas inlet and outlet hole to a predetermined permeability. 
     
     
         17 . The showerhead electrode assembly of  claim 1 , wherein the semiconductor plasma processing chamber is a plasma etch chamber. 
     
     
         18 . The showerhead electrode assembly of  claim 1 , wherein the Si containing gas distribution member is a gas distribution plate. 
     
     
         19 . The showerhead electrode assembly of  claim 1 , wherein the formed carbon member is formed from graphite. 
     
     
         20 . The showerhead electrode assembly of  claim 1 , wherein the Si containing material is SiC.