High density plasma oxidation

Abstract

A method of oxidizing a substrate having area of about 30,000 mm 2 or more. The surface is preferably comprised of silicon-containing materials, such as silicon, silicon germanium, silicon carbide, silicon nitride, and metal silicides. A mixture of oxygen-bearing gas and diluent gas normally non-reactive to oxygen, such as Ne, Ar, Kr, Xe, and/or Rn are ionized to create a plasma having an electron density of at least about 1 e12 cm −3 and containing ambient electrons having an average temperature greater than about 1 eV. The substrate surface is oxidized with energetic particles, comprising primarily atomic oxygen, created in the plasma to form an oxide film of substantially uniform thickness. The oxidation of the substrate takes place at a temperature below about 700° C., e.g., between about room temperature, 20° C., and about 500° C.

1 - 19 . (canceled)  
   
   
       20 . A high density radio frequency plasma reactor system for oxidizing a substrate comprising: 
 a containment structure for creating and maintaining a plasma;    a substrate within the containment structure, the substrate having a substrate surface area comprised of dissimilar silicon-containing materials capable of being converted to an oxide and having a surface area of at least 30,000 mm 2 ; and    a plasma, over the surface of said substrate, created from a mixture of oxygen gas and a diluent gas normally non-reactive to oxygen, said plasma having an electron density of at least about 1 e12 cm −3  and being capable of oxidizing the substrate surface with energetic particles created in the plasma to form an oxide film of substantially uniform thickness such that oxide film thickness variation between the dissimilar materials is less than 20%.    
   
   
       21 . The system of  claim 20  wherein said energetic particles comprise primarily atomic oxygen.  
   
   
       22 . The system of  claim 20  wherein the oxygen gas comprises between 100% and 95% of the mixture by mole fraction.  
   
   
       23 . The system of  claim 20  wherein the diluent gas comprises between 90% and 5% of the mixture by mole fraction.  
   
   
       24 . The system of  claim 20  wherein the oxidation of the substrate takes place at a temperature below 700° C.  
   
   
       25 . The system of  claim 20  wherein the oxidation of the substrate takes place at a temperature of between 20° C. and 500° C.  
   
   
       26 . The system of  claim 20  wherein the plasma contains ambient electrons having an average temperature greater than 1 eV.  
   
   
       27 . The system of  claim 20  wherein the dissimilar silicon-containing materials are selected from the group consisting of silicon, silicon germanium, silicon carbide, silicon nitride, and metal silicides.  
   
   
       28 . The system of  claim 20  wherein the dissimilar silicon-containing materials are monocrystalline silicon having multiple crystallographic planes.  
   
   
       29 . The system of  claim 28  wherein the multiple crystallographic planes include at least two of the following crystallographic planes: (100), (110), and (111).  
   
   
       30 . The system of  claim 20  wherein the surface of the substrate converted to an oxide has a non-uniformity of less than 2% at 1σ standard deviation.  
   
   
       31 . The system of  claim 20  wherein the oxygen gas comprises between 10% and 95% of the mixture by mole fraction and the diluent gas comprises between 90% and 5% of the mixture by mole fraction.  
   
   
       32 . The system of  claim 20  wherein the plasma contains ambient electrons having an average temperature greater than 1 eV and said energetic particles comprise primarily atomic oxygen.