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An electroless deposition solution of the invention for forming an alkali-metal-free coating on a substrate comprises a first-metal ion source for producing first-metal ions, a pH adjuster in the form of a hydroxide for adjusting the pH of the solution, a reducing agent, which reduces the first-meta

An electroless deposition solution of the invention for forming an alkali-metal-free coating on a substrate comprises a first-metal ion source for producing first-metal ions, a pH adjuster in the form of a hydroxide for adjusting the pH of the solution, a reducing agent, which reduces the first-metal ions into the first metal on the substrate, a complexing agent for keeping the first-metal ions in the solution, and a source of ions of a second element for generation of second-metal ions that improve the corrosion resistance of the aforementioned coating. The method of the invention consists of the following steps: preparing hydroxides of a metal such as Ni and Co by means of a complexing reaction, in which solutions of hydroxides of Ni and Co are obtained by displacing hydroxyl ions OH? beyond the external boundary of ligands of mono- or polydental complexants; preparing a complex composition based on a tungsten oxide WO3 or a phosphorous tungstic acid, such as H3[P(W3O10)4], as well as on the use of tungsten compounds for improving anti-corrosive properties of the deposited films; mixing the aforementioned solutions of salts of Co, Ni, or W and maintaining under a temperatures within the range of 20° C. to 100° C.; and carrying out deposition from the obtained mixed solution.

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1. An electroless deposition solution for forming an alkali-metal-free coating on a substrate, said electroless desposition solution comprising:ions of a first metal; a pH adjuster in the form of a quaternary ammonium hydroxide for adjusting the pH of said solution; a reducing agent, which reduces s

1. An electroless deposition solution for forming an alkali-metal-free coating on a substrate, said electroless desposition solution comprising:ions of a first metal; a pH adjuster in the form of a quaternary ammonium hydroxide for adjusting the pH of said solution; a reducing agent, which reduces said first-metal ions into a first layer of said alkali-metal-free coating on said substrate; at least one complexing agent comprising an inorganic phosphorous oxocompound for keeping said first-metal ions in said electroless deposition solution prior to being reduced into the first layer; and ions of a second metal distinct from the first metal, that improve the corrosion resistance of said alkali-metal-free coating. 2. The electroless deposition solution of claim 1, wherein said first metal comprises cobalt.3. The electroless deposition solution of claim 1, wherein said first metal comprises nickel.4. The electroless deposition solution of claim 1, wherein said quaternary-ammonium hydroxide is selected from the group consisting of: tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, methyltriethylammonium hydroxide, ethyltrimethylammonium hydroxide, benzyltrimethylammonium hydroxide, phenyltrimethylammonium hydroxide, methyltripropylammonium hydroxide, and any compound of formula R1R2R3R4NOH, where R1, R2, R3 and R4 comprise the same or different alkyl, aryl, or alkylaryl groups, where said alkyl groups comprise the general formula CnH2n+1, and where aryl and alkylaryl groups comprise benzyl and benzylalkyl of C6H5 and C6H5?CnH2n+1, respectively.5. The electroless deposition solution of claim 1, wherein said quaternary-ammonium hydroxide is selected from the group consisting of: tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide.6. The electroless deposition solution of claim 1, wherein said reducing agent is selected from the group consisting of alkyl, dialkyl and trialkyl amine boranes of the general formula: R1R2R3NH3?nBH3, where R1, R2, and R3 comprise the same or different alkyl groups and n is the number of alkyl groups attached to said amine boranes, where n can be 0, 1, 2, and 3 methyl.7. The electroless deposition solution of claim 1, wherein said reducing agent is selected from the group consisting of hypophosphite, hydrazine, dimethylamine borane.8. The electroless deposition solution of claim 7, wherein said hypophosphite comprises a source of phosphorous for said alkali-metal free coating and is introduced into said solution in the form of a compound selected from the group consisting of hypophosphorous acid, an alkali-metal-free salt of hypophosphorous acid, and a complex of a hypophosphoric acid.9. The electroless deposition solution of claim 1, wherein said at least one complexing agent comprises pyrophosphate.10. The electroless deposition solution of claim 9, wherein said pyrophosphate is introduced into said electroless deposition solution as pyrophosphoric acid.11. The electroless deposition solution of claim 1, wherein said second metal comprises tungsten.12. The electroless deposition solution of claim 1, wherein said second metal is selected from the group consisting of the 4th period of the periodic table, 5th period of the periodic table, and 6th period of the periodic table.13. The electroless deposition solution of claim 12, wherein said second metal selected from the 4th period of the periodic table is selected from the group consisting of Cr, Ni, Cu, and Zn, said second metal selected from the 5th period of the periodic table is selected from the group consisting of Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, and Sb, and said second metal selected from the 6th period of the periodic table is selected from the group consisting of W, Re, Os, Ir, Pt, Au, Tl, and Bi.14. The electroless deposition solution of claim 1, further comprising a buffering agent.15. The electroless deposition solution of claim 14, wherein said buffering agent is a boric acid solution for maintaining pH of said electroless deposition solution within the range of 8 to 10.16. The electroless deposition solution of claim 1, wherein said alkali-metal-free coating is a cobalt tungsten phosphorous alloy film having a phosphorous content of 2% to 14% and a tungsten content of 0.5% to 5%, said electroless deposition solution comprising: cobalt ions, tungsten ions, a hypophosphite reducing agent for said cobalt and tungsten ions, and a pH adjustor.17. The electroless deposition solution of claim 1, wherein said alkali-metal-free coating comprises a barrier layer for the formation of copper interconnects in integrated circuits of semiconductor devices and is formed from a material selected from the group consisting of Co0.9W0.02P0.08, Co0.9P0.1, Co0.96W0.0436, B0.004, C0.9Mo0.03P0.08.18. A method for preparing an electroless deposition solution, comprising dissolving a metal hydroxide in an acidic complexing agent to generate ions of a first metal.19. The method of claim 18, wherein the step of dissolving the metal hydroxide comprises dissolving cobalt hydroxide in an acidic complexing agent.20. The method of claim 19, wherein the cobalt hydroxide is substantially absent of cobalt (III) compounds.21. The method of claim 19, wherein the step of dissolving the cobalt hydroxide comprises dissolving the cobalt hydroxide in a citric acid salt solution to produce a molar ratio of citrate to cobalt greater than approximately 4.0.22. The method of claim 18, wherein the step of dissolving the metal hydroxide comprises dissolving nickel hydroxide in an acidic complexing agent.23. The method of claim 18, wherein the step of dissolving the metal hydroxide comprises dissolving the metal hydroxide in a citric acid solution substantially absent of sodium and ammonia.24. The method of claim 18, wherein the step of dissolving the metal hydroxide comprises dissolving the metal hydroxide in ethylenediaminetetraacetic acid.25. The method of claim 18, wherein the step of dissolving the metal hydroxide comprises dissolving the metal hydroxide in a citric acid solution substantially absent of sodium and ammonia.26. The method of claim 18, further comprising mixing a compound comprising tungsten with the metal hydroxide and acidic complexing agent.27. The method of claim 26, wherein the compound comprises phosphorous tungstic acid or tungstic acid.28. The method of claim 26, wherein the compound comprises tungsten oxide.29. The method of claim 28, further comprising adding an alkylammonin hydroxide with the tungsten oxide.30. The method of claim 29, wherein the alkylammonium hydroxide solution comprises an alkylammonium hydroxide heavier than tetramethylammonium hydroxide.31. The method of claim 30, wherein the alkylammonium hydroxide solution is selected from a group consisting of tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide.32. A method for preparing an electroless deposition solution, comprising dissolving tungsten oxide in a solution comprising an alkylammonium hydroxide heavier than tetramethylammonium hydroxide to produce tungsten ions.33. The method of claim 32, wherein the alkylammonium hydroxide is selected from a group consisting of tetramethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide.34. The method of claim 32, further comprising mixing a metal ion source distinct from the tungsten oxide, a reducing agent and at least one complexing agent in the solution comprising an alkylammonium hydroxide heavier than tetramethylammonium hydroxide.35. The method of claim 34, wherein the step of mixing the metal ion source within the solution comprises dissolving a metal ion source substantially free of alkali metals.36. The method of claim 34, wherein the steps of mixing the metal ion source and the complexing agent within the solution comprises dissolving the metal hydroxide within the complexing agent to produce metal ions distinct from the tungsten ions.37. The method of claim 34, wherein the step of mixing the metal ion source within the solution comprises dissolving metal salts within the solution.38. The method of claim 34, wherein the step of mixing the complexing agent within the solution comprises mixing an inorganic phosphorus oxocompound within the solution.39. The method of claim 34, wherein the step of mixing the complexing agent within the solution comprises mixing ethylenediaminetetraacetic acid within the solution.40. The method of claim 34, wherein the step of mixing the reducing agent within the solution comprises mixing a component selected from the group consisting of hypophosphite, hydrazine, and dimethylamine borane.41. The method of claim 40, wherein the step of mixing the metal ion source within the solution comprises mixing a cobalt compound within the solution such that a molar ratio of cobalt and tungsten to hypophosphite is between approximately 0.4 and approximately 0.9.42. The method of claim 32, further comprising mixing polypropylene glycol within the solution comprising an alkylammonium hydroxide heavier than tetramethylammonium hydroxide.43. The method of claim 32, wherein the step of mixing the polypropylene glycol within the solution comprises adding between approximately 0.01 g/L and approximately 0.1 g/L of polypropylene glycol.