Multiple precursor concentric delivery showerhead

Abstract

A method and apparatus that may be utilized for chemical vapor deposition and/or hydride vapor phase epitaxial (HVPE) deposition are provided. In one embodiment, the apparatus provides a processing chamber that includes a showerhead with separate inlets and channels for delivering separate processing gases into a processing volume of the chamber without mixing the gases prior to entering the processing volume. In one embodiment, a plurality of concentric tube assemblies are disposed within the showerhead to separately deliver a first gas from a first gas channel and a second gas from a second gas channel into the processing volume of the chamber. In one embodiment, the showerhead further includes a heat exchanging channel through which the plurality of concentric tube assemblies is disposed.

1 . A showerhead apparatus, comprising:
 a first gas channel coupled to a first gas inlet;   a second gas channel coupled to a second gas inlet, wherein the first gas channel is isolated from the second gas channel;   a temperature control channel coupled to a heat exchanging system configured to supply a heat exchanging fluid through the temperature control channel;   a plurality of first gas conduits extending through the temperature control channel and fluidly coupling the first gas channel to an exit surface of the showerhead apparatus; and   a plurality of second gas conduits extending through the temperature control channel and fluidly coupling the second gas channel to the exit surface of the showerhead apparatus, wherein at least one of the first gas conduits is disposed within at least one of the second gas conduits.   
     
     
         2 . The apparatus of  claim 1 , wherein each of the first and second gas conduits forms a concentric tube assembly. 
     
     
         3 . The apparatus of  claim 2 , wherein the concentric tube assemblies are configured in a hexagonal close packed arrangement. 
     
     
         4 . The apparatus of  claim 3 , wherein the first gas channel is disposed above the second gas channel. 
     
     
         5 . The apparatus of  claim 4 , wherein the second gas channel is disposed above the temperature control channel. 
     
     
         6 . The apparatus of  claim 2 , further comprising a blocker plate positioned between the first gas inlet and the first gas channel. 
     
     
         7 . The apparatus of  claim 2 , wherein the showerhead apparatus has a plurality of gas passages disposed about the periphery of the exit surface, wherein the plurality of gas passages are fluidly coupled to a purge gas inlet, and wherein the plurality of gas passages are isolated from the first gas channel, the second gas channel, and the temperature control. 
     
     
         8 . The apparatus of  claim 2 , wherein the first gas inlet is coupled to a metal organic gas source, and wherein the second gas inlet is coupled to a nitrogen containing gas source. 
     
     
         9 . A substrate processing apparatus, comprising:
 a chamber body;   a substrate support; and   a showerhead apparatus, wherein a processing volume is defined by the chamber body, the substrate support, and the showerhead apparatus, and wherein the showerhead apparatus comprises:
 a first gas channel coupled to a first gas inlet; 
 a second gas channel coupled to a second gas inlet, wherein the first gas channel is isolated from the second gas channel; 
 a temperature control channel coupled to a heat exchanging system configured to supply a heat exchanging fluid through the temperature control channel; 
 a plurality of first gas conduits extending through the temperature control channel and fluidly coupling the first gas channel to the processing volume; and 
 a plurality of second gas conduits extending through the temperature control channel and fluidly coupling the second gas channel to the processing volume, wherein at least one of the first gas conduits is concentrically disposed within at least one of the second gas conduits. 
   
     
     
         10 . The apparatus of  claim 9 , wherein each of the first and second gas conduits forms a concentric tube assembly. 
     
     
         11 . The apparatus of  claim 10 , wherein the concentric tube assemblies are configured in a hexagonal close packed arrangement. 
     
     
         12 . The apparatus of  claim 9 , wherein the showerhead further comprises a blocker plate disposed between the first gas inlet and the first gas channel. 
     
     
         13 . The apparatus of  claim 9 , wherein the showerhead has a plurality of gas passages disposed about the periphery of a surface of the showerhead adjacent the processing volume, wherein the plurality of gas passages are fluidly coupled to a purge gas inlet, and wherein the plurality of gas passages are isolated from the first gas channel, the second gas channel, and the temperature control channel. 
     
     
         14 . The apparatus of  claim 9 , wherein the first gas inlet is coupled to a metal organic gas source, and wherein the second gas inlet is coupled to a nitrogen containing gas source. 
     
     
         15 . The apparatus of  claim 9 , wherein the second gas channel is disposed between the first gas channel and the temperature control channel. 
     
     
         16 . A method of processing substrates, comprising:
 introducing a first gas into a processing volume of a processing chamber through a first gas inlet coupled to a first gas channel of a showerhead assembly;   introducing a second gas into the processing volume of the processing chamber through a second gas inlet coupled to a second gas channel of the showerhead assembly, wherein the first gas channel is isolated from the second gas channel, wherein the first gas is delivered into the processing volume through a plurality of first plurality of second gas conduits, and wherein at least one of the first gas conduits is concentrically disposed within at least one of the second gas conduits; and   cooling the showerhead assembly by flowing a heat exchanging fluid through a temperature control channel disposed in the showerhead assembly, wherein the plurality of first and second gas conduits are disposed through the heat exchanging channel.   
     
     
         17 . The method of  claim 16 , further comprising distributing the first gas across the first gas channel using a blocker plate disposed between the first gas inlet and the first gas channel. 
     
     
         18 . The method of  claim 16 , further comprising introducing a purge gas about the perimeter of the processing volume through a plurality of gas passages disposed about the periphery of a surface of the showerhead assembly adjacent the processing volume. 
     
     
         19 . The method of  claim 16 , wherein the first gas is a metal organic precursor and the second gas is a nitrogen containing gas. 
     
     
         20 . The method of  claim 19 , wherein the metal organic precursor contains gallium and the nitrogen containing gas is ammonia.