Source reagent compositions for CVD formation of high dielectric constant and ferroelectric metal oxide thin films and method of using same

Abstract

Chemical vapor deposition (CVD) precursor compositions for forming metal oxide high dielectric constant (κ) thin films. The precursor composition in one embodiment comprises a metal precursor having a general formula M(β-diketonate) 2 (OR) 2 , wherein M is Hf, Zr or Ti, and R is t-butyl. The precursor composition may also comprise a solvent medium selected from the group consisting of ethers, glymes, tetraglymes, amines, polyamines, alcohols, glycols, aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, cyclic ethers, and compatible combinations of two or more of the foregoing.

1 . A liquid source reagent composition, comprising a metal precursor of the formula:  
     
       
         
         
             
             
         
       
       wherein:  
       M is Hf or Ti;  
       each of R 1 , R 2 , R 3 , and R 4  is independently selected from the group consisting of H, aryl, perfluoroaryl, C 1 -C 8  alkyl, and C 1 -C 8  perfluoroalkyl; and  
       R 5  and R 6  are both t-butyl groups;  
       wherein said metal precursor is dissolved or suspended in a solvent medium.  
     
   
   
       2 . The liquid source reagent composition of  claim 1 , wherein the solvent medium comprises a solvent species selected from the group consisting of ethers, glymes, tetraglymes, amines, polyamines, aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, cyclic ethers, and compatible combinations of two or more of the foregoing.  
   
   
       3 . The liquid source reagent composition of  claim 1 , wherein the solvent medium comprises at least one of the solvent species of octane, butyl acetate, pmdeta, toluene and pentane.  
   
   
       4 . The liquid source reagent composition of  claim 1 , wherein M is Hf.  
   
   
       5 . The liquid source reagent composition of  claim 1 , wherein M is Ti.  
   
   
       6 . The liquid source reagent composition of  claim 1 , wherein the metal precursor comprises Hf(OtBu) 2 (diketone) 2 .  
   
   
       7 . The liquid source reagent composition of  claim 1 , wherein the metal precursor comprises Hf(OtBu) 2 (thd) 2 .  
   
   
       8 . The liquid source reagent composition of  claim 1 , wherein the metal precursor comprises Ti(OtBu) 2 (diketone) 2 .  
   
   
       9 . The liquid source reagent composition of  claim 1 , wherein the metal precursor comprises Ti(OtBu) 2 (thd) 2 .  
   
   
       10 . The liquid source reagent composition of  claim 6 , wherein the diketone is selected from the group consisting of:  
     
       
         
               
               
             
                   
               
                   
               
                 2,4-pentanedione 
                 (acac); 
               
                 1,1,1-trifluoro-2,4-pentanedionato 
                 (tfac); 
               
                 1,1,1,5,5,5-hexafluoro-2,4-pentanedionato 
                 (hfac); 
               
                 2,2,6,6-tetramethyl-3,5-heptanedionato 
                 (thd); 
               
                 2,2,7-trimethyl-3,5-octanedionato 
                 (tod); 
               
                 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionato 
                 (fod). 
               
                   
               
                   
               
           
              
              
             
             
              
              
              
              
              
              
              
              
             
          
         
       
     
   
   
       11 . The liquid source reagent composition of  claim 8 , wherein the diketone is selected from the group consisting of:  
     
       
         
               
               
             
                   
               
                   
               
                 2,4-pentanedione 
                 (acac); 
               
                 1,1,1-trifluoro-2,4-pentanedionato 
                 (tfac); 
               
                 1,1,1,5,5,5-hexafluoro-2,4-pentanedionato 
                 (hfac); 
               
                 2,2,6,6-tetramethyl-3,5-heptanedionato 
                 (thd); 
               
                 2,2,7-trimethyl-3,5-octanedionato 
                 (tod); 
               
                 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionato 
                 (fod). 
               
                   
               
                   
               
           
              
              
             
             
              
              
              
              
              
              
              
              
             
          
         
       
     
   
   
       12 . A vapor phase source reagent composition comprising a metal precursor of the formula:  
     
       
         
         
             
             
         
       
       wherein:  
       M is H for Ti;  
       each of R 1 , R 2 , R 3 , and R 4  is independently selected from the group consisting of H, aryl, perfluoroaryl, C 1 -C 8  alkyl, and C 1 -C 8  perfluoroalkyl; and  
       R 5  and R 6  are both t-butyl groups.  
     
   
   
       13 . The vapor phase source reagent composition of  claim 12 , wherein M is Hf.  
   
   
       14 . The vapor phase source reagent composition of  claim 12 , wherein M is Ti.  
   
   
       15 . The vapor phase source reagent composition of  claim 12 , further comprising a solvent medium.  
   
   
       16 . The vapor phase source reagent composition of  claim 15 , wherein said solvent medium comprises a solvent species selected from the group consisting of ethers, glymes, tetraglymes, amines, polyamines, aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, cyclic ethers, and compatible combinations of two or more of the foregoing.  
   
   
       17 . The vapor phase source reagent composition of  claim 15 , wherein the solvent medium comprises at least one of the solvent species of octane, butyl acetate, pmdeta, toluene and pentane.  
   
   
       18 . The vapor phase source reagent composition of  claim 15 , wherein the solvent medium comprises octane and pmdeta.  
   
   
       19 . The vapor phase source reagent composition of  claim 15 , wherein the solvent medium comprises butyl acetate and pmdeta.  
   
   
       20 . A composition comprising a mixture of precursors, wherein said precursors are of the formula:  
     
       
         
         
             
             
         
       
       wherein:  
       M is Hf, Zr or Ti, and the mixture of precursors includes at least two different M precursors;  
       each of R 1 , R 2 , R 3 , and R 4  is independently selected from the group consisting of H, aryl, perfluoroaryl, C 1 -C 8  alkyl, and C 1 -C 8  perfluoroalkyl; and  
       R 5  and R 6  are both t-butyl groups.