Diffusion barriers comprising a self-assembled monolayer

Abstract

The present invention provides a method for forming a diffusion barrier layer, a diffusion barrier in an integrated circuit and an integrated circuit. The method for forming a diffusion barrier involves the following steps: 1) preparing a silicon substrate; 2) contacting the silicon substrate with a composition comprising self-assembled monolayer subunits and a solvent; and, 3) removing the solvent. The diffusion barrier layer includes a self-assembled monolayer. The integrated circuit includes a silicon substrate, a diffusion barrier layer and a metal deposited on the diffusion barrier layer. The diffusion barrier layer in the integrated circuit is covalently attached to the silicon substrate and includes a self-assembled monolayer.

What is claimed is:  
     
         1 . A method for forming a diffusion barrier layer comprising the steps of: 
 a) preparing a silicon substrate;    b) contacting the silicon substrate with a composition comprising self-assembled monolayer subunits and a solvent; and,    c) removing the solvent thereby forming the diffusion barrier.    
     
     
         2 . The method according to  claim 1 , wherein the self-assembled monolayer subunit is of the following structure:  
       
         
           
           
               
               
           
         
       
       wherein Y is an O-alkyl group, and wherein R 2  is an alkyl group, heteroalkyl group, aryl group or heteroaryl group.  
     
     
         3 . The method according to  claim 1 , wherein the self-assembled monolayer subunit is of the following structure:  
       
         
           
           
               
               
           
         
       
       wherein Y is a halogen, and wherein R 2  is an alkyl group, heteroalkyl group, aryl group or heteroaryl group.  
     
     
         4 . The method according to  claim 1 , wherein the silicon substrate preparation comprises the formation of a silicon oxide surface.  
     
     
         5 . The method according to  claim 1 , wherein the method further comprises the step of heating the silicon substrate and the composition during contact.  
     
     
         6 . The method according to  claim 2 , wherein R 2  is an alkyl group of the following structure:  
       
         
           
           
               
               
           
         
       
       wherein R 3 , R 4  and R 5  are independently selected from the group consisting of hydrogen, alkyl groups, heteroalkyl groups, halo groups, NH 2 , NHR 6 , NR 6 R 7 , OH, OR 6 , SH, SR 6 , CHO, COOH and CN, and wherein R 6  and R 7  are alkyl groups, and wherein n is an integer ranging from 1 to 5.  
     
     
         7 . The method according to  claim 2 , wherein R 2  is an alkyl group of the following structure:  
       
         
           
           
               
               
           
         
       
       wherein R 3  and R 4  are independently selected from the group consisting of hydrogen, alkyl groups, heteroalkyl groups, halo groups, NH 2 , NHR 6 , NR 6 R 7 , OH, OR 6 , SH, SR 6 , CHO, COOH and CN, and wherein R 6  and R 7  are alkyl groups, and wherein n is an integer ranging from 1 to 5.  
     
     
         8 . The method according to  claim 6 , wherein Y is OCH 3 .  
     
     
         9 . The method according to  claim 7 , wherein Y is OCH 3 .  
     
     
         10 . The method according to  claim 8 , wherein R 3 , R 4  and R 5  are hydrogen and n is 2.  
     
     
         11 . The method according to  claim 9 , wherein R 2  is an alkyl group of the following structure:  
       
         
           
           
               
               
           
         
       
       and wherein R 3  and R 4  are hydrogen and n is 2.  
     
     
         12 . A diffusion barrier layer in an integrated circuit, wherein the diffusion barrier comprises a self-assembled monolayer.  
     
     
         13 . The diffusion barrier according to  claim 12 , wherein the self-assembled monolayer comprises subunits, and wherein the subunits are of the following structure:  
       
         
           
           
               
               
           
         
       
       wherein R 2  is an alkyl group, heteroalkyl group, aryl group or heteroaryl group.  
     
     
         14 . The diffusion barrier according to  claim 13 , wherein R 2  is an alkyl group of the following structure:  
       
         
           
           
               
               
           
         
       
       wherein R 3 , R 4  and R 5  are independently selected from the group consisting of hydrogen, alkyl groups, heteroalkyl groups, halo groups, NH 2 , NHR 6 , NR 6 R 7 , OH, OR 6 , SH, SR 6 , CHO, COOH and CN, and wherein R 6  and R 7  are alkyl groups, and wherein n is an integer ranging from 1 to 5.  
     
     
         15 . The diffusion barrier according to  claim 13 , wherein R 2  is an alkyl group of the following structure:  
       
         
           
           
               
               
           
         
       
       wherein R 3  and R 4  are independently selected from the group consisting of hydrogen, alkyl groups, heteroalkyl groups, halo groups, NH 2 , NHR 6 , NR 6 R 7 , OH, OR 6 , SH, SR 6 , CHO, COOH and CN, and wherein R 6  and R 7  are alkyl groups, and wherein n is an integer ranging from 1 to 5.  
     
     
         16 . The diffusion barrier according to  claim 14 , wherein R 3 , R 4  and R 5  are hydrogen and n is 2.  
     
     
         17 . The diffusion barrier according to  claim 15 , wherein R 2  is an alkyl group of the following structure:  
       
         
           
           
               
               
           
         
       
       and wherein R 3  and R 4  are hydrogen and n is 2.  
     
     
         18 . An integrated circuit comprising a silicon substrate, a diffusion barrier layer and a metal deposited on the diffusion barrier layer, wherein the diffusion barrier is covalently attached to the silicon substrate, and wherein the diffusion barrier is a self-assembled monolayer.  
     
     
         19 . The integrated circuit according to  claim 18 , wherein the self-assembled monolayer comprises subunits of the following structure:  
       
         
           
           
               
               
           
         
       
       wherein R 2  is an alkyl group, heteroalkyl group, aryl group or heteroaryl group.  
     
     
         20 . The integrated circuit according to  claim 19 , wherein R 2  is an alkyl group of the following structure:  
       
         
           
           
               
               
           
         
       
       wherein R 3 , R 4  and R 5  are independently selected from the group consisting of hydrogen, alkyl groups, heteroalkyl groups, halo groups, NH 2 , NHR 6 , NR 6 R 7 , OH, OR 6 , SH, SR 6 , CHO, COOH and CN, and wherein R 6  and R 7  are alkyl groups, and wherein n is an integer ranging from 1 to 5.  
     
     
         21 . The integrated circuit according to  claim 19 , wherein R 2  is an alkyl group of the following structure:  
       
         
           
           
               
               
           
         
       
       wherein R 3  and R 4  are independently selected from the group consisting of hydrogen, alkyl groups, heteroalkyl groups, halo groups, NH 2 , NHR 6 , NR 6 R 7 , OH, OR 6 , SH, SR 6 , CHO, COOH and CN, and wherein R 6  and R 7  are alkyl groups, and wherein n is an integer ranging from 1 to 5.  
     
     
         22 . The integrated circuit according to  claim 20 , wherein R 3 , R 4  and R 5  are hydrogen and n is 2.  
     
     
         23 . The integrated circuit according to  claim 21 , wherein R 2  is an alkyl group of the following structure:  
       
         
           
           
               
               
           
         
       
       and wherein R 4  are hydrogen and n is 2.