Organometallic compounds, processes for the preparation thereof and methods of use thereof

Abstract

This invention relates to organometallic precursor compounds represented by the formula (Cp(R′) x ) y M(H) z-y , a process for producing the organometallic precursor compounds, and a method for depositing a metal and/or metal carbide layer, e.g., Ta metal and/or TaC layer, on a substrate by the thermal or plasma enhanced disassociation of the organometallic precursor compounds, e.g., by CVD or ALD techniques. The metal and/or metal carbide layer is useful as a liner or barrier layer for conducting metals and high dielectric constant materials in integrated circuit manufacturing.

1 . A process for producing a compound having the formula (Cp(R′) x ) y M(H) z-y  wherein M is a metal selected from tantalum (Ta), tungsten (W), molybdenum (Mo), niobium (Nb), vanadium (V) or chromium (Cr), each R′ is the same or different and represents a halogen atom, an acyl group having from 1 to about 12 carbon atoms, an alkoxy group having from 1 to about 12 carbon atoms, an alkoxycarbonyl group having from 1 to about 12 carbon atoms, an alkyl group having from 1 to about 12 carbon atoms, an amine group having from 1 to about 12 carbon atoms or a silyl group having from 0 to about 12 carbon atoms, Cp is a substituted or unsubstituted cyclopentadienyl group or a substituted or unsubstituted cyclopentadienyl-like group, x is an integer from 0 to 5, y is an integer from 1 to 5, and z is the valence of M, which process comprises reacting a metal halide, a cyclopentadienyl salt and a reducing agent in the presence of a first solvent and under reaction conditions sufficient to produce an intermediate reaction material, and reacting said intermediate reaction material with a base material in the presence of a second solvent and under reaction conditions sufficient to produce said compound. 
     
     
         2 . The process of  claim 1  wherein said metal halide comprises tantalum pentachloride, niobium pentachloride, vanadium pentachloride, tungsten hexachloride, molybdenum hexachloride or chromium hexachloride; said cyclopentadienyl salt comprises sodium cyclopentadiene, potassium cyclopentadiene, lithium cyclopentadiene or magnesocene; said reducing agent comprises sodium bis(2-methoxyethoxy)aluminum dihydride, sodium borohydride or lithium aluminum hydride; said first solvent comprises dimethoxyethane (DME), toluene or mixtures thereof; said intermediate reaction material comprises bis(cyclopentadienyl)(dihydrido)tantalum(bis-(2-methoxyethoxy)aluminate; said base material comprises sodium hydroxide, potassium hydroxide or ethyl acetate; and said second solvent comprises toluene, hexane or mixtures thereof. 
     
     
         3 . A method for producing a film, coating or powder by decomposing an organometallic precursor, said organometallic precursor having the formula (Cp(R′) x ) y M(H) z-y  wherein M is a metal selected from tantalum (Ta), tungsten (W), molybdenum (Mo), niobium (Nb), vanadium (V) or chromium (Cr), each R′ is the same or different and represents a halogen atom, an acyl group having from 1 to about 12 carbon atoms, an alkoxy group having from 1 to about 12 carbon atoms, an alkoxycarbonyl group having from 1 to about 12 carbon atoms, an alkyl group having from 1 to about 12 carbon atoms, an amine group having from 1 to about 12 carbon atoms or a silyl group having from 0 to about 12 carbon atoms, Cp is a substituted or unsubstituted cyclopentadienyl group or a substituted or unsubstituted cyclopentadienyl-like group, x is an integer from 0 to 5, y is an integer from 1 to 5, and z is the valence of M, thereby producing said film, coating or powder, a method wherein the organometallic precursor is selected from bis(cyclopentadienyl)(allyl)tantalum, bis(cyclopentadienyl)(alkene)(hydrido)tantalum, bis(cyclopentadienyl)(trihydrido)tantalum or bis(cyclopentadienyl)(trialkyl)tantalum. 
     
     
         4 . A method for processing a substrate in a processing chamber, said method comprising (i) introducing an organometallic precursor into said processing chamber, said organometallic precursor having the formula (Cp(R′) x ) y M(H) z-y  wherein M is a metal selected from tantalum (Ta), tungsten (W), molybdenum (Mo), niobium (Nb), vanadium (V) or chromium (Cr), each R′ is the same or different and represents a halogen atom, an acyl group having from 1 to about 12 carbon atoms, an alkoxy group having from 1 to about 12 carbon atoms, an alkoxycarbonyl group having from 1 to about 12 carbon atoms, an alkyl group having from 1 to about 12 carbon atoms, an amine group having from 1 to about 12 carbon atoms or a silyl group having from 0 to about 12 carbon atoms, Cp is a substituted or unsubstituted cyclopentadienyl group or a substituted or unsubstituted cyclopentadienyl-like group, x is an integer from 0 to 5, y is an integer from 1 to 5, and z is the valence of M, (ii) heating said substrate to a temperature of about 100° C. to about 400° C., and (iii) disassociating said organometallic precursor in the presence of a processing gas to deposit a metal layer on said substrate. 
     
     
         5 . The method of  claim 4  wherein the organometallic precursor is selected from bis(cyclopentadienyl)(allyl)tantalum, bis(cyclopentadienyl)(alkene)(hydrido)tantalum, bis(cyclopentadienyl)(trihydrido)tantalum or bis(cyclopentadienyl)(trialkyl)tantalum. 
     
     
         6 . The method of  claim 4  wherein Ta or TaC is deposited on said substrate. 
     
     
         7 . The method of  claim 4  wherein said metal layer is deposited on said substrate by chemical vapor deposition, atomic layer deposition, plasma assisted chemical vapor deposition or plasma assisted atomic layer deposition. 
     
     
         8 . The method of  claim 4  wherein said processing gas is selected from hydrogen, argon, helium, or combinations thereof. 
     
     
         9 . The method of  claim 4  wherein disassociating the precursor further comprises generating a plasma at a power density between about 0.6 Watts/cm 2  and about 3.2 Watts/cm 2 . 
     
     
         10 . The method of  claim 4  further comprising exposing the deposited metal layer to a plasma generated at a power density between about 0.6 Watts/cm 2  and about 3.2 Watts/cm 2 . 
     
     
         11 . The method of  claim 4  furthering comprising depositing a second metal layer on the metal layer, said second metal layer comprising copper that is deposited by an electroplating technique. 
     
     
         12 . A method for forming a metal material on a substrate from an organometallic precursor, said method comprising vaporizing said organometallic precursor to form a vapor, and contacting the vapor with the substrate to form said metal material thereon, wherein the precursor is represented by the formula (Cp(R′) x ) y M(H) z-y  wherein M is a metal selected from tantalum (Ta), tungsten (W), molybdenum (Mo), niobium (Nb), vanadium (V) or chromium (Cr), each R′ is the same or different and represents a halogen atom, an acyl group having from 1 to about 12 carbon atoms, an alkoxy group having from 1 to about 12 carbon atoms, an alkoxycarbonyl group having from 1 to about 12 carbon atoms, an alkyl group having from 1 to about 12 carbon atoms, an amine group having from 1 to about 12 carbon atoms or a silyl group having from 0 to about 12 carbon atoms, Cp is a substituted or unsubstituted cyclopentadienyl group or a substituted or unsubstituted cyclopentadienyl-like group, x is an integer from 0 to 5, y is an integer from 1 to 5, and z is the valence of M, and a method wherein the organometallic precursor is represented by the formula 
       
         
           
           
               
               
           
         
       
       wherein R 1 , R 2  and each R are the same or different and each represent a halogen atom, an acyl group having from 1 to about 12 carbon atoms, an alkoxy group having from 1 to about 12 carbon atoms, an alkoxycarbonyl group having from 1 to about 12 carbon atoms, an alkyl group having from 1 to about 12 carbon atoms, an amine group having from 1 to about 12 carbon atoms or a silyl group having from 0 to about 12 carbon atoms, a method wherein the substrate comprises a microelectronic device structure. 
     
     
         13 . A method for forming a metal material on a substrate from an organometallic precursor, said method comprising vaporizing said organometallic precursor to form a vapor, and contacting the vapor with the substrate to form said metal material thereon, wherein the substrate comprises a microelectronic device structure, and wherein the precursor is represented by the formula (Cp(R′) x ) y M(H) z-y  wherein M is a metal selected from tantalum (Ta), tungsten (W), molybdenum (Mo), niobium (Nb), vanadium (V) or chromium (Cr), each R′ is the same or different and represents a halogen atom, an acyl group having from 1 to about 12 carbon atoms, an alkoxy group having from 1 to about 12 carbon atoms, an alkoxycarbonyl group having from 1 to about 12 carbon atoms, an alkyl group having from 1 to about 12 carbon atoms, an amine group having from 1 to about 12 carbon atoms or a silyl group having from 0 to about 12 carbon atoms, Cp is a substituted or unsubstituted cyclopentadienyl group or a substituted or unsubstituted cyclopentadienyl-like group, x is an interger from 0 to 5, y is an interger from 1 to 5, and z in the valence of M. 
     
     
         14 . A method for processing a substrate in a processing chamber, said method comprising (i) introducing an organometallic precursor into said processing chamber, said organometallic precursor having the formula (Cp(R′) x ) y M(H) z-y  wherein M is a metal selected from tantalum (Ta), tungsten (W), molybdenum (Mo), niobium (Nb), vanadium (V) or chromium (Cr), each R′ is the same or different and represents a halogen atom, an acyl group having from 1 to about 12 carbon atoms, an alkoxy group having from 1 to about 12 carbon atoms, an alkoxycarbonyl group having from 1 to about 12 carbon atoms, an alkyl group having from 1 to about 12 carbon atoms, an amine group having from 1 to about 12 carbon atoms or a silyl group having from 0 to about 12 carbon atoms, Cp is a substituted or unsubstituted cyclopentadienyl group or a substituted or unsubstituted cyclopentadienyl-like group, x is an integer from 0 to 5, y is an integer from 1 to 5, and z is the valence of M, (ii) heating said substrate to a temperature of about 100° C. to about 400° C., and (iii) disassociating said organometallic precursor in the presence of a processing gas to deposit a metal layer on said substrate, wherein disassociating the precursor further comprises generating a plasma at a power density between about 0.6 Watts/cm 2  and about 3.2 Watts/cm 2 . 
     
     
         15 . A method for processing a substrate in a processing chamber, said method comprising (i) introducing an organometallic precursor into said processing chamber, said organometallic precursor having the formula (Cp(R′) x ) y M(H) z-y  wherein M is a metal selected from tantalum (Ta), tungsten (W), molybdenum (Mo), niobium (Nb), vanadium (V) or chromium (Cr), each R′ is the same or different and represents a halogen atom, an acyl group having from 1 to about 12 carbon atoms, an alkoxy group having from 1 to about 12 carbon atoms, an alkoxycarbonyl group having from 1 to about 12 carbon atoms, an alkyl group having from 1 to about 12 carbon atoms, an amine group having from 1 to about12 carbon atoms or a silyl group having from 0 to about 12 carbon atoms, Cp is a substituted, or unsubstituted cyclopentadienyl group or a substituted or unsubstituted syclopentadienyl-like group, x is an integer from 0 to 5, y is an interger from 1 to 5, and z is the valence of M, (ii) heading said substrate to a temperature of about 100° C. to about 400° C., and (iii) disassociating said organometallic precursor in the presence of a processing gas to deposit a metal layer on said substrate, and further comprising exposing the deposited metal layer to a plasma generated at a power density between about 0.6 Watts/cm 2  and about 3.2 Watts/cm 2 .