Method of making an integrated circuit including electrodeposition of aluminium

Abstract

A method of making an integrated circuit including composition of matter for electrodepositing of aluminium is disclosed. One embodiment includes a bath having a solution of selected aluminium salts in a substantially anhydrous organic solvent, to uses of certain aluminium salts for electrodepositing and to processes for electrodepositing aluminium.

1 . A composition of matter for electrodepositing of aluminium comprising a bath comprising a solution of an aluminium salt selected from
 halogenated aluminium alcoholate; or   aluminium salts with an anion with strongly electron-withdrawing groups; in a substantially anhydrous organic solvent.   
     
     
         2 . The composition of  claim 1 , wherein the alcoholate anion of the aluminium alcoholate is selected from halogenated methanolate, halogenated ethanolate, halogenated isopropanolate, halogenated n-propanolate, halogenated iso-butanolate, halogentated n-butanolate; or halogenated tert. butanolate. 
     
     
         3 . The composition of  claim 1 , wherein the alcoholate anion of the halogenated aluminium alcoholate is a compound according to any of general formulas Ia, Ib, Ic, Id, Ie, If or Ig 
       
         
           
           
               
               
           
         
         wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 are independently from one another selected from hydrogen, or halogen, with at last one of R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 being halogen. 
       
     
     
         4 . The composition of  claim 3 , wherein more than half of R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 in any given anion are halogen. 
     
     
         5 . The composition of  claim 3 , wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 are independently from one another selected from hydrogen, F or Cl, preferably are F or Cl, more preferably are either all F or all Cl; or
 wherein R1, R2, R3, R4, R5, R6, R7, R8 and R9 are independently from one another selected from hydrogen, F or Cl, while R10, R11, and R12 are hydrogen, preferably wherein R1, R2, R3, R4, R5, R6, R7, R8 and R9 are independently from one another selected from F or Cl, while R10, R11, and R12 are hydrogen, more preferably wherein R1, R2, R3, R4, R5, R6, R7, R8 and R9 are either all F or all Cl, while R10, R11, and R12 are hydrogen.   
     
     
         6 . The composition of  claim 3 , wherein the alcoholate anion of the halogenated aluminium alcoholate is a compound according to general formula Ib. 
     
     
         7 . The composition of  claim 6 , wherein R1, R2, R3, R11 and R12 are independently from one another selected from hydrogen, F or Cl, preferably are F or Cl, more preferably are either all F or all Cl; or
 wherein R1, R2, and R3 are independently from one another selected from hydrogen, F or Cl, while R11, and R12 are hydrogen, preferably wherein R1, R2, and R3 are independently from one another selected from F or Cl, while R11, and R12 are hydrogen, more preferably wherein R1, R2, and R3 are either all F or all Cl, while R11, and R12 are hydrogen.   
     
     
         8 . The composition of  claim 1 , wherein the anion with the strongly electron withdrawing groups is selected from
 penta-halogenated benzoate, preferably from C6F5 COO—, or C6C15 COO—;   substituted sulfonate anions, preferably from sulfonate anions of any of general structure II   
       
         
           
           
               
               
           
         
         wherein R21 is selected from optionally at least mono substituted C 1-4 Alkyl, or toluoyl (p-toluene); or 
         halogenated carboxylic acid anions, preferably of general structures IIIa, IIIb, IIIc, or IIId 
       
       
         
           
           
               
               
           
         
         wherein R31, R32, R33, R34, R35, R36, and R37 are independently from one another selected from hydrogen, or halogen, with at last one, preferably at least half of R31, R32, R33, R34, R35, R36, and R37 being halogen. 
       
     
     
         9 . The composition of  claim 8 , wherein
 R21 is selected from optionally at least mono substituted CH3, CF3, CCl3, or toluoyl (p-toluene); or   R31, R32, R33, R34, R35, R36, and R37 are independently from one another selected from hydrogen, F or Cl, with at last half of R31, R32, R33, R34, R35, R36, and R37 being F or Cl.   
     
     
         10 . The composition of  claim 1 , wherein the organic solvent is selected from aprotic organic solvents or from organic solvents not forming a complex with the aluminum salts of  claims 1  to  9  or from organic solvents having a donator power of between 30 and 10, preferably of between 25 and 12, or from solvents in which the aluminium salts of  claim 1  to  9  may be dissolved. 
     
     
         11 . The composition of  claim 1 , wherein the organic solvent has a water content of less than 1%, preferably of equal to or less than 0.5%, more preferably of equal to or less than 0.25%, most preferably of equal to or less than 0.15%. 
     
     
         12 . The composition of  claim 1 , wherein the organic solvent is selected from
 Acetonitril, Tetrahydrofuran (THF), tert.butyl-methyl ether;   or carbonates, preferably selected from dimethyl carbonate, or propylene glycol carbonate (4-Methyl-1,3-dioxolan-2-on);   or carboxylic acid esters; preferably selected from ethyl acetate.   
     
     
         13 . The composition of  claim 1 , wherein the aluminium salt is present in the bath in an amount greater than or equal to 0.1 mol/kg of solvent or in a concentration of between 0.05 and 5 mol/kg of solvent. 
     
     
         14 . The composition of  claim 1 , wherein the bath is additionally comprising at least one further electrolyte, preferably a nonaqueous electrolyte, more preferable a phosphate, alkyl-sulfonate, borate, antimonite or arsenate; most preferably is selected from hexafluorophosphates, tris(pentafluoroethyl)trifluorphosphate, methanesulfonates, trifluoromethanesulfonates, tetrafluoroborates, bis[oxalato(2-)]borate, bis[silicylato(2-)]borate, bis[1,2-benzenediolato(2-)-0,0′]borate, hexafluoroanitmonate, or hexafluoroarsenate; or is selected from hexafluorophosphates, or tetrafluoroborates. 
     
     
         15 . The composition of  claim 1 , additionally comprising an anode and cathode; preferably a soluble aluminium anode. 
     
     
         16 . The composition of  claim 1 , wherein the composition does also comprise a means for excluding oxygen or humidity or both from the bath, preferably from the surface of the bath or of the solution comprised within the bath; preferably in the form of a sealing, or lid covering the surface of the bath or of the solution comprised within the bath or a means for introducing a protective gas to the surface of the bath or of the solution comprised within the bath; or combinations thereof. 
     
     
         17 . Use of an aluminium salt selected from
 halogenated aluminium alcoholate; or   aluminium salts with an anion with strongly electron-withdrawing groups; for electrodepositing aluminium.   
     
     
         18 . Use of  claim 17 , wherein the alcoholate anion of the aluminium alcoholate is selected from halogenated methanolate, halogenated ethanolate, halogenated isopropanolate, halogenated n-propanolate, halogenated iso-butanolate, halogentated n-butanolate; or halogenated tert. butanolate. 
     
     
         19 . Use of  claim 17 , wherein the alcoholate anion of the halogenated aluminium alcoholate is a compound according to any of general formulas Ia, Ib, Ic, Id, Ie, If or Ig 
       
         
           
           
               
               
           
         
         wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 are independently from one another selected from hydrogen, or halogen, with at last one of R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 being halogen. 
       
     
     
         20 . Use of  claim 19 , wherein more than half of R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 in any given anion are halogen. 
     
     
         21 . Use of  claim 19 , wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 are independently from one another selected from hydrogen, F or Cl, preferably are F or Cl, more preferably are either all F or all Cl; or
 wherein R1, R2, R3, R4, R5, R6, R7, R8 and R9 are independently from one another selected from hydrogen, F or Cl, while R10, R11, and R12 are hydrogen, preferably wherein R1, R2, R3, R4, R5, R6, R7, R8 and R9 are independently from one another selected from F or Cl, while R10, R11, and R12 are hydrogen, more preferably wherein R1, R2, R3, R4, R5, R6, R7, R8 and R9 are either all F or all Cl, while R10, R11, and R12 are hydrogen.   
     
     
         22 . Use of  claim 19 , wherein the alcoholate anion of the aluminium alcoholate is a compound according to general formula Ib. 
     
     
         23 . Use of  claim 22 , wherein R1, R2, R3, R11 and R12 are independently from one another selected from hydrogen, F or Cl, preferably are F or Cl, more preferably are either all F or all Cl; or
 wherein R1, R2, and R3 are independently from one another selected from hydrogen, F or Cl, while R11, and R12 are hydrogen, preferably wherein R1, R2, and R3 are independently from one another selected from F or Cl, while R11, and R12 are hydrogen, more preferably wherein R1, R2, and R3 are either all F or all Cl, while R11, and R12 are hydrogen.   
     
     
         24 . Use of  claim 17 , wherein the anion with strongly electron withdrawing groups is selected from
 penta-halogenated benzoate, preferably from C6F5 COO—, or C6Cl5 COO—;   substituted sulfonate anions, preferably from sulfonate anions of any of general structure II   
       
         
           
           
               
               
           
         
         wherein R21 is selected from optionally at least mono substituted C1-4Alkyl, or toluoyl (p-toluene); or 
         halogenated carboxylic acid anions, preferably of general structures IIIa, IIIb, IIIc, or IIId 
       
       
         
           
           
               
               
           
         
         wherein R31, R32, R33, R34, R35, R36, and R37 are independently from one another selected from hydrogen, or halogen, with at last one, preferably at least half of R31, R32, R33, R34, R35, R36, and R37 being halogen. 
       
     
     
         25 . Use of  claim 24 , wherein
 R21 is selected from optionally at least mono substituted CH3, CF3, CCl3, or toluoyl (p-toluene); or   R31, R32, R33, R34, R35, R36, and R37 are independently from one another selected from hydrogen, F or Cl, with at last half of R31, R32, R33, R34, R35, R36, and R37 being F or Cl.   
     
     
         26 . Use according to  claim 17 , characterized in that the aluminium is electrodeposited on a conductive surface, preferably a conductive surface selected from metals, alloys of metals and conductive polymers more preferably on a metal surface of a conductive metal, preferably a metal being selected from
 Ag, Au, Cr, Cu, Fe, Ge, Ir, Mn, Mo, Nb, Ni, Pd, Pt, Si, Ta, Ti, V, W, Zn or In, Pb, Sb and Sn;   
       more preferably from
 Ag, Au, Cr, Cu, Fe, Ge, Ir, Mn, Mo, Nb, Ni, Pd, Pt, Si, Ta, Ti, V, W, or Zn; or from alloys of these metals. 
 
     
     
         27 . Use according to  claim 17 , characterized in that the aluminium is electrodeposited for the purpose of creating a new package material, for pattern plating or for replacing sputtering on or creating of a conductive surface, or for anticorrosive protection or for layering—optionally with other metals. 
     
     
         28 . A process for electrodepositing of aluminium from a bath, wherein by using an electrode and an anode being arranged at least partly inside the bath an electric current is applied to the bath comprising a solution of an aluminium salt with an anion selected from
 halogenated aluminium alcoholate; or   aluminium salts with an anion with strongly electron-withdrawing groups in a substantially anhydrous organic solvent.   
     
     
         29 . The process of  claim 28 , wherein the anode is a soluble aluminium anode. 
     
     
         30 . The process of  claim 28 , wherein no physical barrier or membrane is blocking the flow of the organic solvent between the cathode and anode. 
     
     
         31 . The process of  claim 28 , wherein oxygen or humidity or both are excluded from the surface of the bath; preferably by using a sealing, or lid covering the surface of the bath or of the solution comprised within the bath or a means for introducing a protective gas to the surface of the bath or of the solution comprised within the bath; or combinations thereof. 
     
     
         32 . The process of  claim 28 , wherein the alcoholate anion of the aluminium alcoholate is selected from halogenated methanolate, halogenated ethanolate, halogenated isopropanolate, halogenated n-propanolate, halogenated iso-butanolate, halogentated n-butanolate; or halogenated tert. butanolate. 
     
     
         33 . The process of  claim 28 , wherein the alcoholate anion of the aluminium alcoholate is a compound according to any of general formulas Ia, Ib, Ic, Id, Ie, If or Ig 
       
         
           
           
               
               
           
         
         wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 are independently from one another selected from hydrogen, or halogen, with at last one of R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 being halogen. 
       
     
     
         34 . The process of  claim 33 , wherein more than half of R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 in any given anion are halogen. 
     
     
         35 . The process of  claim 33 , wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and R12 are independently from one another selected from hydrogen, F or Cl, preferably are F or Cl, more preferably are either all F or all Cl; or
 wherein R1, R2, R3, R4, R5, R6, R7, R8 and R9 are independently from one another selected from hydrogen, F or Cl, while R10, R11, and R12 are hydrogen, preferably wherein R1, R2, R3, R4, R5, R6, R7, R8 and R9 are independently from one another selected from F or Cl, while R10, R11, and R12 are hydrogen, more preferably   wherein R1, R2, R3, R4, R5, R6, R7, R8 and R9 are either all F or all Cl, while R10, R11, and R12 are hydrogen.   
     
     
         36 . The process of  claim 33 , wherein the alcoholate anion of the halogenated aluminium alcoholate is a compound according to general formula Ib. 
     
     
         37 . The process of  claim 36 , wherein R1, R2, R3, R11 and R12 are independently from one another selected from hydrogen, F or Cl, preferably are F or Cl, more preferably are either all F or all Cl; or
 wherein R1, R2, and R3 are independently from one another selected from hydrogen, F or Cl, while R11, and R12 are hydrogen, preferably wherein R1, R2, and R3 are independently from one another selected from F or Cl, while R11, and R12 are hydrogen, more preferably wherein R1, R2, and R3 are either all F or all Cl, while R11, and R12 are hydrogen.   
     
     
         38 . The process of  claim 28 , wherein the anion with strongly electron withdrawing groups is selected from
 penta-halogenated benzoate, preferably from C6F5 COO—, or C6C15 COO—;   substituted sulfonate anions, preferably from sulfonate anions of any of general structure II   
       
         
           
           
               
               
           
         
         wherein R21 is selected from optionally at least mono substituted C1-4Alkyl, or toluoyl (p-toluene); or 
         halogenated carboxylic acid anions, preferably of general structures IIIa, IIIb, IIIc, or IIId 
       
       
         
           
           
               
               
           
         
         wherein R31, R32, R33, R34, R35, R36, and R37 are independently from one another selected from hydrogen, or halogen, with at last one, or preferably at least half of R31, R32, R33, R34, R35, R36, and R37 being halogen. 
       
     
     
         39 . The process of  claim 38 , wherein
 R21 is selected from optionally at least mono substituted CH3, CF3, CCl3, or toluoyl (p-toluene); or   R31, R32, R33, R34, R35, R36, and R37 are independently from one another selected from hydrogen, F or Cl, with at last half of R31, R32, R33, R34, R35, R36, and R37 being F or Cl.   
     
     
         40 . The process of  claim 28 , wherein the organic solvent is selected from aprotic organic solvents or from organic solvents not forming a complex with Cr (II) or Cr (III) or its respective salts or from organic solvents having a donator power of between 30 and 10, preferably of between 25 and 12, or from solvents in which the aluminium salts may be dissolved. 
     
     
         41 . The process of  claim 28 , wherein the organic solvent has a water content of less than 1%, preferably of equal to or less than 0.5%, more preferably of equal to or less than 0.25%, most preferably of equal to or less than 0.15%. 
     
     
         42 . The process of  claim 28 , wherein the organic solvent is selected from
 Acetonitril, Tetrahydrofuran (THF), tert.butyl-methyl ether;   or carbonates, preferably selected from dimethyl carbonate, or propylene glycol carbonate (4-Methyl-1,3-dioxolan-2-on);   or carboxylic acid esters; preferably selected from ethyl acetate.   
     
     
         43 . The process of  claim 28 , wherein the bath is additionally comprising at least one further electrolyte, preferably a nonaqueous electrolyte, more preferable a phosphate, alkyl-sulfonate, borate, antimonite or arsenate; most preferably is selected from hexafluorophosphates, tris(pentafluoroethyl)trifluorphosphate, methanesulfonates, trifluoromethanesulfonates, tetrafluoroborates, bis[oxalato(2-)]borate, bis[silicylato(2-)]borate, bis[1,2-benzenediolato(2-)-0,0′ ]borate, hexafluoroanitmonate, or hexafluoroarsenate; or is selected from hexafluorophosphates, or tetrafluoroborates. 
     
     
         44 . An integrated circuit comprising:
 a composition of matter for electrodepositing of aluminium comprising a bath comprising a solution of an aluminium salt selected from   halogenated aluminium alcoholate; or   aluminium salts with an anion with strongly electron-withdrawing groups; in a substantially anhydrous organic solvent.   
     
     
         45 . A process for making an integrated circuit comprising:
 electrodepositing of aluminium from a bath, wherein by using an electrode and an anode being arranged at least partly inside the bath an electric current is applied to the bath comprising a solution of an aluminium salt with an anion selected from   halogenated aluminium alcoholate; or   aluminium salts with an anion with strongly electron-withdrawing groups in a substantially anhydrous organic solvent.