Methods for forming a boron nitride film by a plasma enhanced atomic layer deposition process

Abstract

Methods for forming a boron nitride film by a plasma enhanced atomic layer deposition (PEALD) process are provided. The methods may include: providing a substrate into a reaction chamber; and performing at least one unit deposition cycle of a PEALD process, wherein a unit cycle comprises, contacting the substrate with a vapor phase reactant comprising a boron precursor, wherein the boron precursor comprises less than or equal to two halide atoms per boron atom; and contacting the substrate with a reactive species generated from a gas comprising a nitrogen precursor.

What is claimed is: 
     
         1 . A method for forming a boron nitride film by a plasma enhanced atomic layer deposition (PEALD) process, the method comprising:
 providing a substrate into a reaction chamber; and   performing at least one unit deposition cycle of a PEALD process, wherein a unit deposition cycle comprises:
 contacting the substrate with a vapor phase reactant comprising a boron precursor, wherein the boron precursor comprises less than or equal to two halide atoms per boron atom; and 
 contacting the substrate with a reactive species generated from a plasma produced from a gas comprising a nitrogen precursor. 
   
     
     
         2 . The method of  claim 1 , wherein the boron precursor comprises a boron halide precursor. 
     
     
         3 . The method of  claim 2 , wherein the boron halide precursor comprises at least one of a boron chloride precursor, a boron iodide precursor, or a boron bromide precursor. 
     
     
         4 . The method of  claim 2 , wherein the boron halide precursor further comprises hydrogen. 
     
     
         5 . The method of  claim 2 , wherein the boron halide precursor further comprises a hydrocarbon group. 
     
     
         6 . The method of  claim 2 , wherein the boron halide precursor further comprises an amine group. 
     
     
         7 . The method of  claim 2 , wherein the boron halide precursor comprises a compound having the general chemical formula: 
       
         
           
           
               
               
           
         
         wherein X=Cl, Br, or I, and R=H, C x H y , or N x C y H z . 
       
     
     
         8 . The method of  claim 2 , wherein the boron halide precursor comprises a compound having the general chemical formula: 
       
         
           
           
               
               
           
         
         wherein X=Cl, Br, or I, and R=H, C x H y , or N x C y H z . 
       
     
     
         9 . The method of  claim 2 , wherein the boron halide precursor comprises a compound having the general chemical formula: 
       
         
           
           
               
               
           
         
         wherein X=Cl, Br, or I, and R=H, C x H y , or N x C y H z , and L=N x H y , N x H y C z , or C x H y . 
       
     
     
         10 . The method of  claim 2 , wherein the boron halide precursor comprises a compound having the general chemical formula: 
       
         
           
           
               
               
           
         
         wherein X=Cl, Br, or I, and R=H, C x H y , or N x C y H z . 
       
     
     
         11 . The method of  claim 1 , wherein the nitrogen precursor comprises at least one of ammonia (NH 3 ), or N2/H2. 
     
     
         12 . The method of  claim 1 , further comprising regulating the pressure within the reaction chamber during the PEALD process to less than 300 Pascals. 
     
     
         13 . The method of  claim 1 , further comprising heating the substrate to a deposition temperature of less than 500° C. 
     
     
         14 . The method of  claim 1 , wherein the boron nitride film consists essentially of boron and nitrogen. 
     
     
         15 . The method of  claim 1 , wherein the boron nitride film comprises a carbon doped boron nitride. 
     
     
         16 . The method of  claim 1 , wherein the boron nitride film has a wet etch rate ratio (WERR) to thermal silicon oxide in dilute hydrofluoric acid (1:100) of less than 0.5. 
     
     
         17 . The method of  claim 16 , wherein the boron nitride film has a wet etch rate ratio (WERR) to thermal silicon oxide in dilute hydrofluoric acid (1:100) of less than 0.4. 
     
     
         18 . The method of  claim 1 , wherein the boron nitride film has a wet etch rate in dilute hydrofluoric acid (1:100) of less than 1 nanometer/minute. 
     
     
         19 . The method of  claim 1 , wherein the growth rate of the boron nitride film is greater than 0.05 nanometers per cycle. 
     
     
         20 . The method of  claim 1 , wherein the boron nitride is deposited over a non-planar substrate with a step coverage of greater than 90 percentage.