Method and apparatus for precleaning a substrate surface prior to epitaxial growth

Abstract

Embodiments of the present invention generally relate to methods for removing contaminants and native oxides from substrate surfaces. The methods generally include removing contaminants disposed on the substrate surface using a plasma process, and then cleaning the substrate surface by use of a remote plasma assisted dry etch process.

1 . A processing system, comprising:
 a first processing chamber; and   a controller configured to cause a process to be performed in the processing system, the process comprising:
 removing carbon containing contaminants from a native oxide layer on a surface of a substrate by performing a reducing process using a hydrogen containing plasma in the first processing chamber; and 
 removing the native oxide layer from the substrate by performing an etch process using a fluorine containing plasma in the first processing chamber. 
   
     
     
         2 . The processing system of  claim 1 , wherein the hydrogen containing plasma is generated using H 2  gas. 
     
     
         3 . The processing system of  claim 1 , wherein the hydrogen containing plasma is generated using NH 3  gas. 
     
     
         4 . The processing system of  claim 1 , wherein the fluorine containing plasma is generated using a F 2  gas. 
     
     
         5 . The processing system of  claim 1 , wherein the fluorine containing plasma is generated using NF 3  gas. 
     
     
         6 . The processing system of  claim 1 , wherein the etch process further comprises:
 exposing the substrate to the fluorine containing plasma, producing solid by-products on the surface of the substrate; and   raising the temperature of the substrate to remove the solid by-products from the surface of the substrate.   
     
     
         7 . The processing system of  claim 6 , wherein the temperature of the substrate is raised to 120° C. or more to remove the solid by-products from the surface of the substrate via sublimation. 
     
     
         8 . The processing system of  claim 1 , wherein the hydrogen containing plasma is an inductively coupled plasma. 
     
     
         9 . The processing system of  claim 1 , wherein the hydrogen containing plasma is a capacitively coupled plasma. 
     
     
         10 . The processing system of  claim 1 , wherein removing the native oxide layer from the substrate comprises removing a native oxide of at least one of silicon, germanium, or silicon germanium. 
     
     
         11 . The processing system of  claim 1 , further comprising a second processing chamber configured to form an epitaxial layer on the substrate in the second processing chamber after the native oxide layer is removed from the substrate. 
     
     
         12 . A method, comprising:
 introducing a hydrogen containing plasma to a native oxide layer formed on a surface of a substrate to remove carbon containing contaminants from the native oxide layer in a processing chamber; and   introducing a fluorine containing plasma to the surface of the substrate to remove the native oxide layer from the substrate in the processing chamber.   
     
     
         13 . The method of  claim 12 , wherein the hydrogen containing plasma is generated using H 2  gas. 
     
     
         14 . The method of  claim 12 , wherein the hydrogen containing plasma is generated using NH 3  gas. 
     
     
         15 . The method of  claim 12 , wherein the fluorine containing plasma is generated using a F 2  gas. 
     
     
         16 . The method of  claim 12 , wherein the fluorine containing plasma is generated using NF 3  gas. 
     
     
         17 . The method of  claim 12 , further comprising:
 exposing the substrate to the fluorine containing plasma, producing solid by-products on the surface of the substrate; and   raising the temperature of the substrate to remove the solid by-products from the surface of the substrate.   
     
     
         18 . The method of  claim 17 , wherein the temperature of the substrate is raised to 120° C. or more to remove the solid by-products from the surface of the substrate via sublimation. 
     
     
         19 . The method of  claim 12 , wherein the hydrogen containing plasma is an inductively coupled plasma. 
     
     
         20 . The method of  claim 12 , wherein the hydrogen containing plasma is a capacitively coupled plasma.