Volatile copper(II) complexes for deposition of copper films by atomic layer deposition

Abstract

The present invention relates to novel 1,3-diimine copper complexes and the use of 1,3-diimine copper complexes for the deposition of copper on substrates or in or on porous solids in an Atomic Layer Deposition process. This invention also provides a process for making amino-imines and novel amino-imines.

1 . A process for forming copper deposits on a substrate comprising: 
 a. contacting a substrate with a copper complex, (I), to form a deposit of the copper complex on the substrate; and                          b. contacting the deposited copper complex with a reducing agent,    wherein    R 1  and R 4  are independently selected from the group consisting of H, C 1 -C 5  alkyl, and dimethylamino;    R 2  and R 3  are independently selected from the group consisting of H, C 1 -C 5  alkyl, phenyl, benzyl, and 4-pyridinyl, with the proviso that the total number of carbons in R 1 -R 4  is 4-12; and    the reducing agent is selected from the group consisting of 9-BBN, borane, dihydrobenzofuran, pyrazoline, diethylsilane, dimethylsilane, ethylsilane, methylsilane, phenylsilane and silane.    
     
     
         2 . The process of  claim 1 , wherein R 1 , R 3  and R 4  are methyl and R 2  is phenyl.  
     
     
         3 . The process of  claim 1 , wherein the substrate is selected from the group consisting of copper, silicon wafers and silicon dioxide coated with a barrier layer.  
     
     
         4 . The process of  claim 1 , wherein the substrate is exposed to a vapor of the copper complex.  
     
     
         5 . The process of  claim 1 , wherein the deposition is carried out at 0 to 120° C.  
     
     
         6 . The process of  claim 1 , wherein the reducing agent is silane or diethylsilane.  
     
     
         7 . A 1,3-diimine copper complex, (II),  
       
         
           
           
               
               
           
         
       
       wherein 
 R 5  and R 8  are dimethylamino; and  
 R 6  and R 7  are independently selected from the group consisting of H, C 1 -C 5  alkyl, phenyl, benzyl, and 4-pyridinyl, with the proviso that the total number of carbons in, R 5 -R 8  is 4-14; or  
 R 5  and R 8  are independently selected from the group consisting of H, C 1 -C5 alkyl, and dimethylamino; and  
 R 6  and R 7  are selected from the group consisting of H, C 1 -C 5  alkyl, phenyl, benzyl, and 4-pyridinyl, with the proviso that either R 6  or R 7  is 4-pyridinyl, and the proviso that the total number of carbons in R 5 -R 8  is 4-14.  
 
     
     
         8 . The 1,3-diimine copper complex of  claim 7 , wherein R 5  and R 8  are dimethylamino.  
     
     
         9 . An article, comprising the 1,3-diimine copper complexes, (II), of  claim 7 , deposited on a substrate.  
     
     
         10 . The article of  claim 9 , wherein the substrate is selected from the group of copper, silicon wafers, and silicon dioxide coated with a barrier layer.  
     
     
         11 . The article of  claim 10 , wherein the barrier layer is selected from the group consisting of tantalum, tantalum nitride, titanium, titanium nitride, tantalum silicon nitride, titanium silicon nitride, tantalum carbon nitride, and niobium nitride.  
     
     
         12 . A process for the synthesis of diimines comprising: 
 a. contacting an alkylimino-monoketone, (III), with an alkylating agent to form the corresponding O-alkylated derivative, (IV);                          b. contacting the O-alkylated derivative, (IV), of step (a) with a primary alkyl amine, NH 2 R 13 , to form an immonium salt, (V); and                          c. contacting the immonium salt, (V), of step (b) with a strong base to form the corresponding neutral amino-imine (VI):                          wherein    R 10  and R 11  are independently selected from the group consisting of H, C 1 -C 5  alkyl, phenyl, benzyl, and 4-pyridinyl;    R 12  is Me or Et;    R 9  and R 13  are independently selected from the group consisting of H and C 1 -C 5  alkyl, with the proviso that the total number of carbons in R 9 , R 10 , R 11  and R 13  is 4-12;    the alkylating agent is selected from the group consisting of dimethyl sulfate, methyl benzenesulfonate, methyltoluenesulfonate, diethyl sulfate, ethylbenzenesulfonate, methyltrifluoromethanesulfonate and ethyl toluenesulfonate; and    X −  is an anion derived from the alkylating agent.    
     
     
         13 . The process of  claim 12 , wherein the alkylating agent is 15 dimethylsulfate.  
     
     
         14 . The process of  claim 12 , wherein R 13  is selected from the group of methyl, ethyl and n-propyl.  
     
     
         15 . The process of  claim 12 , wherein the strong base is selected from the group consisting of sodium methoxide, copper methoxide and potassium tert-butoxide.  
     
     
         16 . A composition, comprising amino-imines, (VII),  
       
         
           
           
               
               
           
         
       
       wherein 
 R 14  and R 17  are independently selected from the group consisting of H, C 1 -C 5  alkyl, and dimethylamino; and  
 R 15  and R 16  are selected from the group consisting of H, C 1 -C 5  alkyl, phenyl, benzyl, and 4-pyridinyl, with the proviso that either R 15  or R 18  is 4-pyridinyl, and the proviso that the total number of carbons in R 14 -R 17  is 4-14.  
 
     
     
         17 . The amino-imine of  claim 16 , wherein R 15  is 4-pyridinyl and R 14 , R 16  and R 17  are C 1 -C 4  alkyl.