Method of making a gas distribution member for a plasma processing chamber
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.
1. A method of making a Si containing gas distribution member which supplies process gas into a semiconductor plasma processing chamber comprising:
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.
2. The method of claim 1 , wherein 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.
3. The method 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.
4. The method of claim 3 , 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.
5. The method of claim 3 , 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.
6. The method of claim 1 , wherein the Si containing material depositing step is performed by a CVD process, a PECVD process, or a cold spray process.
7. The method of claim 1 , wherein the removal of the formed carbon member comprises an ashing process.
8. The method 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.
9. The method 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.
10. The method of claim 1 , wherein each gas inlet and outlet hole is fabricated by a mechanical fabrication technique such as drilling.
11. The method of claim 10 , 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.
12. The method of claim 1 , wherein the semiconductor plasma processing chamber is a plasma etch chamber.
13. The method of claim 1 , wherein the Si containing gas distribution member is a backing plate, thermal control plate, or gas distribution plate.
14. The method of claim 1 , wherein the formed carbon member is formed from graphite.
15. The method of claim 1 , wherein the Si containing material is SiC.