Composition for cobalt plating and method for forming metal wiring using the same

Abstract

The present invention relates to a composition for cobalt plating and a method for forming metal wiring using the same, and more particularly, a composition for cobalt plating comprising a cobalt salt; a chloride or a hydrochloric acid; boric acid; a carbonaceous material; and other additives, and a method for forming a metal wiring using the same, in which the composition for cobalt plating is plated onto a substrate to suppress the thermal expansion of the metal caused by high-temperature processes to achieve excellent high-temperature stability, thereby resulting in prevention of deformation of a substrate even in the absence of any structural modification of the substrate or additional processing.

What is claimed is: 
     
         1 . A composition for cobalt plating comprising:
 a) 0.1 to 30% by weight of a cobalt salt;   b) 0.001 to 5% by weight of chloride or hydrochloric acid;   c) 0.01 to 10% by weight of boric acid;   d) 0.001 to 1% by weight of a carbonaceous material; and   e) a residual amount of a solvent.   
     
     
         2 . The composition for cobalt plating of  claim 1 , further comprising:
 f) 0.0001 to 0.1% by weight of one or more additives selected from the group consisting of accelerators, retarders and leveling agents.   
     
     
         3 . The composition for cobalt plating of  claim 1 , wherein the cobalt salt is one or more selected from the group consisting of cobalt sulfate, cobalt nitrate, and cobalt acetate. 
     
     
         4 . The composition for cobalt plating of  claim 1 , wherein the chloride is cobalt chloride. 
     
     
         5 . The composition for cobalt plating of  claim 1 , wherein the carbonaceous material is one or more selected from the group consisting of carbon black, activated carbon, expanded graphite, graphene, graphene oxide, carbon nanotube, carbon fiber, and graphite. 
     
     
         6 . The composition for cobalt plating of  claim 2 , wherein the accelerator is a sulfo group-containing compound. 
     
     
         7 . The composition for cobalt plating of  claim 6 , wherein the sulfo group-containing compound is one or more selected from the group consisting of disodium 3,3′-dithiobis(1-propanesulfonate), bis(3-sulfopropyl)disulfide, mercaptoethane sulfonic acid, 3-mercapto-1-propanesulfonic acid, 3-N,N-dimethlyaminodithiocarbamoyl-1-propanesulfonic acid, and C1-C20 alkyl sulfonic acid. 
     
     
         8 . The composition for cobalt plating of  claim 2 , wherein the retarder of f) is one or more selected from the group consisting of polyethylene glycol, polypropylene glycol, poly(ethylene glycol-co-propylene glycol), polyethylene glycol-block-polypropylene glycol-block-polyethylene glycol, polyvinyl alcohol, polyethylene oxide, stearyl alcohol polyglycol ether, stearic acid polyglycol ester, oleic acid polyglycol ester, nonylphenol polyglycol ether, octanol polyalkylene glycol ether, and octanediol bis-(polyalkylene glycol ether). 
     
     
         9 . The composition for cobalt plating of  claim 2 , wherein the leveling agent of f) comprises one or more selected from the group consisting of polyimine, polyamine, polyethyleneimine, alkylated polyethyleneimine, polyvinylpyridine, polyvinylpyrrolidone, pyrrole, 2-mercaptothiazoline, 4-mercaptopyridine, ethylenethiourea, thiourea, pyrazole, polyaniline, imidazole, triazole, tetrazole, pentazole, benzimidazole, benzotriazole, oxazole and benzoxazole. 
     
     
         10 . A method for forming a metal wiring, comprising a step of forming a cobalt thin film on a substrate using the composition for cobalt plating of  claim 1 . 
     
     
         11 . The method for forming a metal wiring of  claim 10 , wherein the substrate is one selected from the group consisting of a silicon substrate, a silicon-germanium substrate, a metal oxide single crystal substrate, a silicon on insulator (SOI) substrate, a germanium on insulator (GOI) substrate, and a copper substrate. 
     
     
         12 . The method for forming a metal wiring of  claim 10 , wherein the substrate has a through silicon via (TSV) structure, a damascene, redistribution layer (RDL), or under bump metallurgy (UBM) structure.