Dual Gas Feed Showerhead for Deposition

Abstract

A showerhead utilized within a process chamber includes a first inlet for receiving a first gas from a first source at a center region of an inner plenum defined therein. A plurality of second inlets is defined along a peripheral region of the showerhead for receiving a second gas from a second source. A plurality of conduits couples the edge plenum to an outer edge of the inner plenum so as to supply the second gas to the inner plenum. The first gas creates an inner flow that flows radially outward from the center region to an outer edge of the inner plenum and the second gas supplied by the edge plenum creates a perimeter flow that flows inward from the outer edge of the inner plenum toward the center region. A stagnation point defining an adjustable radius is formed at an interface of the first gas and the second gas. A plurality of outlets are defined across a lower surface of the showerhead and extends a diameter of the inner plenum such that the first gas from the inner flow exits the plurality of outlets from the center region up to the stagnation point and the second gas from the perimeter flow exits the plurality of outlets from the stagnation point to the outer edge.

1 . A showerhead of a substrate processing system used for processing a substrate, comprising:
 an inner plenum coupled to,
 a single first inlet defined at a center of the showerhead to receive a first gas from a first source, the first gas received to create an inner flow that radiates outwardly from a center region of the inner plenum to cover a first radius; 
 a plurality of second inlets defined along an outer edge of the showerhead to receive a second gas from a second source into the inner plenum, the second gas received to create a perimeter flow that radiates inwardly from an outer edge toward the center region of the inner plenum, the perimeter flow extending from an outer edge of the first radius to a second radius in the inner plenum, the first gas and the second gas supplied simultaneously to the inner plenum, the inner flow of the first gas and the perimeter flow of the second gas controlled to dynamically adjust the first radius while keeping the first gas substantially separate from the second gas within the inner plenum; and 
   a plurality of outlets distributed across a lower surface of the showerhead and extend a diameter of the inner plenum, the plurality of outlets configured to separately and simultaneously deliver the first gas from the inner plenum to a first process region and the second gas from the inner plenum to a second process region defined over a substrate, when the substrate is present in the substrate processing system.   
     
     
         2 . The showerhead of  claim 1 , wherein the single first inlet is coupled to the first source via a first flow valve, and the plurality of second inlets is coupled to the second source via one or more second flow valves, and
 a controller coupled to the first flow valve and the one or more second flow valves, the controller configured to generate a first signal to the first flow valve to control a first flow rate of the first gas, and a second signal to the one or more second flow valves to control a second flow rate of the second gas through the plurality of second inlets.   
     
     
         3 . The showerhead of  claim 2 , wherein the first flow valve and the one or more second flow valves are located outside the showerhead. 
     
     
         4 . The showerhead of  claim 2 , wherein the first flow valve and the one or more second flow valves are located inside the showerhead. 
     
     
         5 . The showerhead of  claim 2 , wherein the first signal and the second signal generated by the controller are configured to control flow rates of the first and the second gases supplied simultaneously to the inner plenum, such that a second flow rate of the second gas is defined to be different from a first flow rate of the first gas. 
     
     
         6 . The showerhead of  claim 1 , wherein the plurality of second inlets is coupled to the second source via a central channel disposed to surround the first inlet, the second gas from the second source supplied to the outer edge of the inner plenum is supplied through the central channel. 
     
     
         7 . The showerhead of  claim 1 , wherein the showerhead includes an edge plenum defined along the outer edge and coupled to the plurality of second inlets to receive the second gas from the second source, the edge plenum defined outside of and coupled to the outer edge of the inner plenum via a plurality of conduits to supply the second gas to the inner plenum. 
     
     
         8 . The showerhead of  claim 7 , wherein the edge plenum further includes,
 a distribution plenum configured to equalize the second gas received from the second source; and   an application plenum to receive the second gas from the distribution plenum, a bottom portion of the application plenum coupled to the plurality of conduits to supply the second gas to the outer edge of the inner plenum.   
     
     
         9 . The showerhead of  claim 1 , wherein the inner flow of the first gas and the perimeter flow of the second gas applied simultaneously to the inner plenum define a stagnation point at a separation interface between the first gas and the second gas within the inner plenum, the inner flow of the first gas and the perimeter flow of the second gas controlled to adjust a location of the stagnation point within the inner plenum. 
     
     
         10 . The showerhead of  claim 1 , wherein the first process region is defined in a center of an area defined between an upper chamber body and a lower chamber body of the substrate processing system, the first process region extends for a diameter of the stagnation point defined in the inner plenum, and the second process region is defined to extend from the diameter of the stagnation point to the outer edge of the inner plenum. 
     
     
         11 . The showerhead of  claim 1 , wherein the showerhead is integrated into an upper chamber body of the substrate processing system, the upper chamber body configured to mate with a lower chamber body to provide a tight seal during processing of the substrate. 
     
     
         12 . A process chamber used for processing a substrate, comprising:
 a lower chamber body having a substrate support surface for supporting the substrate;   an upper chamber body configured to mate with the lower chamber body, the upper chamber body having a showerhead, wherein the showerhead comprising:
 an inner plenum coupled to,
 a single first inlet defined at a center of the showerhead to receive a first gas from a first source, the first gas received to create an inner flow that radiates outwardly from a center region of the inner plenum to cover a first radius; 
 a plurality of second inlets defined along an outer edge of the showerhead to receive a second gas from a second source into the inner plenum, the second gas received to create a perimeter flow that radiates inwardly from an outer edge toward the center region of the inner plenum, the perimeter flow extending from an outer edge of the first radius to a second radius in the inner plenum, the first gas and the second gas configured to be supplied simultaneously into the inner plenum, the inner flow of the first gas and the perimeter flow of the second gas controlled to dynamically adjust the first radius while keeping the first gas substantially separate from the second gas within the inner plenum; and 
 
 a plurality of outlets distributed across a lower surface of the showerhead and extend a diameter of the inner plenum, the plurality of outlets configured to separately and simultaneously deliver the first gas from the inner plenum to a first process region and the second gas from the inner plenum to a second process region defined over a substrate, when the substrate is present in the substrate processing system. 
   
     
     
         13 . The system of  claim 12 , wherein the single first inlet of the showerhead is coupled to the first source via a first flow valve, and the plurality of second inlets is coupled to the second source via one or more second flow valves, and
 a controller coupled to the first flow valve and the one or more second flow valves, the controller configured to generate a first signal to the first flow valve to control a first flow rate of the first gas, and a second signal to the one or more second flow valves to control a second flow rate of the second gas through the plurality of second inlets.   
     
     
         14 . The system of  claim 13 , wherein the first flow valve and the one or more second flow valves are located outside the showerhead. 
     
     
         15 . The system of  claim 13 , wherein the first flow valve and the one or more second flow valves are located inside the showerhead. 
     
     
         16 . The system of  claim 13 , wherein the first signal and the second signal generated by the controller are configured to control flow rates of the first and the second gases supplied simultaneously to the inner plenum, such that a second flow rate of the second gas is defined to be different from a first flow rate of the first gas. 
     
     
         17 . The system of  claim 12 , wherein the showerhead includes an edge plenum defined along the outer edge and coupled to the plurality of second inlets to receive the second gas from the second source, the edge plenum defined outside of and coupled to the outer edge of the inner plenum via a plurality of conduits to supply the second gas to the inner plenum. 
     
     
         18 . The system of  claim 17 , wherein the edge plenum of the showerhead further includes,
 a distribution plenum configured to equalize the second gas received from the second source; and   an application plenum to receive the second gas from the distribution plenum, a bottom portion of the application plenum coupled to the plurality of conduits to supply the second gas to the outer edge of the inner plenum.