Methods of reducing chamber residues

Abstract

The present disclosure relates to systems and methods for reducing the formation of hardware residue and minimizing secondary plasma formation during substrate processing in a process chamber. The process chamber may include a gas distribution member configured to flow a first gas into a process volume and generate a plasma therefrom. A second gas is supplied into a lower region of the process volume. Further, an exhaust port is disposed in the lower region to remove excess gases or by-products from the process volume during or after processing.

What is claimed is: 
     
         1 . A method for forming a film, the method comprising:
 introducing a first gas into a process volume of a process chamber, the first gas introduced into the process volume through a lid assembly of the process chamber at a first flow rate, wherein the process volume comprises a substrate disposed on a substrate support;   generating a plasma from the first gas to form a film on the substrate; and   introducing a second gas into the process volume at a second flow rate, the second gas introduced into the process volume via a port separate from the slit valve opening, the port disposed in a sidewall of the process chamber and below the substrate support, the second gas introduced into the process volume simultaneously with the first gas, wherein a ratio of the first flow rate to the second flow rate is between about 0.5 and about 3.   
     
     
         2 . The method of  claim 1 , wherein the second gas is unreactive with the plasma. 
     
     
         3 . The method of  claim 1 , wherein the second gas is formed of a species having a dissociation energy equal to or greater than that of diatomic argon. 
     
     
         4 . The method of  claim 1 , wherein the second gas is selected from the group consisting of argon, ammonia, helium, hydrogen, nitrogen, and oxygen. 
     
     
         5 . The method of  claim 1 , wherein the second gas comprises a purge gas or cleaning gas. 
     
     
         6 . The method of  claim 1 , wherein the second gas forms a dispersion trap for localizing the plasma to a region above the substrate support. 
     
     
         7 . The method of  claim 1 , wherein the second gas reacts with the first gas in a lower region of the process volume to form a reaction byproduct, and the reaction byproduct is exhausted from the process chamber. 
     
     
         8 . The method of  claim 7 , wherein introducing the first gas into the process volume and generating a plasma from the first gas causes dispersion of unreacted precursor species below the substrate support, and wherein the second gas facilitates a spontaneous combustion reaction to consume the unreacted precursor species dispersed below the substrate support. 
     
     
         9 . The method of  claim 1 , wherein a ratio of the first flow rate to the second flow rate is between about 1 and about 2. 
     
     
         10 . A method for forming a film, the method comprising:
 introducing a first gas into a process volume of a process chamber, the first gas introduced into an upper region of the process volume through a lid assembly of the process chamber at a first flow rate, wherein the process volume comprises a substrate disposed on a substrate support;   generating a plasma from the first gas to form a film on the substrate; and   introducing a second gas into the process volume at a second flow rate, the second gas introduced into a lower region of the process volume via a space between the substrate support and a shield disposed below the substrate support, the second gas introduced into the process volume simultaneously with the first gas, wherein a ratio of the first flow rate to the second flow rate is between about 0.5 and about 3.   
     
     
         11 . The method of  claim 10 , wherein the second gas is unreactive with the plasma. 
     
     
         12 . The method of  claim 10 , wherein the second gas is formed of a species having a dissociation energy equal to or greater than that of diatomic argon. 
     
     
         13 . The method of  claim 10 , wherein the second gas is selected from the group consisting of argon, ammonia, helium, hydrogen, nitrogen, and oxygen. 
     
     
         14 . The method of  claim 10 , wherein the second gas comprises a purge gas or cleaning gas. 
     
     
         15 . The method of  claim 10 , wherein the second gas forms a dispersion trap for localizing the plasma to a region above the substrate support. 
     
     
         16 . The method of  claim 10 , wherein the second gas reacts with the first gas in the lower region of the process volume to form a reaction byproduct, and the reaction byproduct is exhausted from the process chamber. 
     
     
         17 . The method of  claim 16 , wherein introducing the first gas into the process volume and generating a plasma from the first gas causes dispersion of unreacted precursor species below the substrate support, and wherein the second gas facilitates a spontaneous combustion reaction to consume the unreacted precursor species dispersed below the substrate support. 
     
     
         18 . The method of  claim 1 , wherein a ratio of the first flow rate to the second flow rate is between about 1 and about 2. 
     
     
         19 . A method for forming a film, the method comprising:
 transferring a substrate into a process volume of a process chamber through a slit valve opening of the process chamber, the substrate transferred onto a substrate support;   introducing a first gas into an upper region of the process volume of the process chamber through a lid assembly of the process chamber at a first flow rate, the lid assembly comprising a gas distribution member having a plurality of openings;   generating a plasma from the first gas to form a film on the substrate disposed on the substrate support;   introducing second gas into the process volume at a second flow rate, the second gas introduced into a lower region of the process volume via an opening in a sidewall of the process chamber and from a space between the substrate support and a shield disposed below the substrate support, the second gas introduced into the process volume simultaneously with the first process gas, wherein a ratio of the first flow rate to the second flow rate is between about 0.5 and about 3; and   exhausting the process volume via a pumping channel of the process chamber.   
     
     
         20 . The method of  claim 19 , wherein the second gas is selected from the group consisting of argon, ammonia, helium, hydrogen, nitrogen, and oxygen.