Tungsten nitrido precursors for the CVD of tungsten nitride, carbonitride, and oxide films
Embodiments of the invention are directed to a method of preparing a WN x , WN x C y , WN x O z , and WN x C y O z solid by the deposition of a WN x precursor at a temperature below 300° C. The WN x precursor is a tungsten nitrido complex. The deposition can be carried out using a tungsten nitrido complex as a single-source metal organic precursor. In an embodiment of the invention, the deposition can be performed to form a plurality of WN x , WN x C y , WN x O z , WN x C y O z nanoparticles.
1. A WN x or WN x C y precursor, comprising a tungsten nitrido complex of formula:
wherein: R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 are independently H, C 1 -C 8 alkyl, C 1 -C 8 perfluoroalkyl, C 1 -C 8 fluorohydroalkyl, or SiR 16 R 17 R 18 ; wherein R 16 , R 17 and R 18 are independently H, C 1 -C 8 alkyl, aryl, C 1 -C 8 perfluoroalkyl, or C 1 -C 8 fluorohydroalkyl; and wherein at least one of R 1 , R 2 , R 3 , R 4 , R 5 , or R 6 is not methyl.
2. A method of preparing a tungsten nitrido complex of the structure
comprising:
providing WCl 6 ;
mixing WCl 6 with trimethylsilyl azide to form [WNCl 3 ] 4 .1.1DCE (DCE=1,2-dichloroethane);
combining the [WNCl 3 ] 4 .1.1DCE with tert-butanol and a stoichiometric quantity of sodium tert-butoxide to form WN(O t Bu) 3 ; and
combining the WN(O t Bu) 3 with one or more compounds of the formula Zr(NR a R b ) 4 to form (I), wherein: R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , are independently R a or R b , wherein R a or R b are independently H, C 1 -C 8 alkyl, C 1 -C 8 perfluoroalkyl, C 1 -C 8 fluorohydroalkyl, or SiR 16 R 17 R 18 ; wherein R 16 , R 17 and R 18 are independently H, C 1 -C 8 alkyl, aryl, C 1 -C 8 perfluoroalkyl, or C 1 -C 8 fluorohydroalkyl.
3. A method of preparing a tungsten nitrido complex of the structure
comprising:
providing WN(N(CH 3 ) 2 ) 3 ;
combining the WN(N(CH 3 ) 2 ) 3 with at least one amine of the formula NHR a R b , wherein: R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 and R 15 are independently R a or R b , wherein R a or R b are independently H, C 1 -C 8 alkyl, C 1 -C 8 perfluoroalkyl, C 1 -C 8 fluorohydroalkyl, or SiR 16 R 17 R 18 ; wherein R 16 , R 17 and R 18 are independently H, C 1 -C 8 alkyl, aryl, C 1 -C 8 perfluoroalkyl, or C 1 -C 8 fluorohydroalkyl, and wherein the amine of the formula NHR a R b is less volatile than NH(CH 3 ) 2 ; and
removing NH(CH 3 ) 2 as a volatile.
4. The WN x or WN x C y precursor, according to claim 1 , wherein R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 are ethyl or propyl.
5. The WN x or WN x C y precursor, according to claim 1 , wherein R 1 , R 3 , and R 5 are methyl and R 2 , R 4 , and R 6 are ethyl or propyl.
6. The WN x or WN x C y precursor, according to claim 1 , wherein R 1 , R 3 , and R 5 are ethyl and R 2 , R 4 , and R 6 are propyl.