Method for manufacturing metal film having high purity

Abstract

Methods for manufacturing metal films, and more particularly, to a method for manufacturing a cobalt film, a rhodium film or an iridium film having high purity via a CVD method without using reaction gas at low deposition temperature. Metal films having high purity may be deposited without impurities such as carbon, hydrogen or oxygen by using disproportionate reaction at low temperature because side-products such as L and MX 3 , which are neutral materials having high vapor pressure, are easily removed from a reactor by vacuum without remaining in the films. Additionally, almost no particles are generated because reaction gas is not used.

What is claimed is:  
     
         1 . A method for manufacturing a metal film comprising: 
 (a) vaporizing a metal precursor M(L)X, where M is a metal, L is a neutral ligand and X is an anion ligand, wherein the metal M has an oxidation number of +1;    (b) adsorbing the vaporized metal precursor on a semiconductor substrate heated to a temperature ranging from 100 to 900° C. to deposit metal layer on the substrate; and    (c) pumping out the side-product generated during the step (b).    
     
     
         2 . The method according to  claim 1 , wherein the metal M is selected from the group consisting of cobalt, rhodium and iridium.  
     
     
         3 . The method according to  claim 1 , wherein the metal precursor is pure solid state of M(L)X or a M(L)X solution having a molarity ranging from 0.05 to 10M.  
     
     
         4 . The method according to  claim 3 , wherein solvent used in the M(L)X solution is selected from the group consisting of C 1 -C 20  alkane, C 2 -C 20  alkene, C 2 -C 20  alkyne, C 1 -C 20  alcohol, C 2 -C 20  ether, C 2 -C 20  carboxylic acid, C 3 -C 20  ester, C 3 -C 20  β-diketone, C 1 -C 20  amine, C 6 -C 20  arene, C 4 -C 20  cyclic alkane, C 3 -C 20  cyclic ether, C 1 -C 20  alkane substituted with halogen, C 2 -C 20  alkene substituted with halogen, C 2 -C 20  alkyne substituted with halogen, C 1 -C 20  alcohol substituted with halogen, C 2 -C 20  ether substituted with halogen, C 2 -C 20  carboxylic acid substituted with halogen, C 3 -C 20  ester substituted with halogen, C 3 -C 20  β-diketone substituted with halogen, C 1 -C 20  amine substituted with halogen, C 6 -C 20  arene substituted with halogen, C 4 -C 20  cyclic alkane substituted with halogen and C 3 -C 20  cyclic ether substituted with halogen.  
     
     
         5 . The method according to  claim 1 , wherein the neutral ligand L is selected from the group consisting of CO, CS, CS 2 , RCN, RNC, OR 2 , SR 2 , NR 3 , PR 3 , NR 2 R′, PR 2 P′, ROR′, RSR′, C 2 -C 20  alkylidene, C 2 -C 20  alkylidyne, C 4 -C 20  cyclic alkylidene, C 4 -C 20  diene, C 6 -C 20  triene, C 4 -C 20  cyclic diene, C 2 -C 20  cyclic triene, C 6 -C 20  arene, C 2 -C 20  ether, C 1 -C 20  amine, C 3 -C 20  cyclic ether, RCN substituted with halogen, RNC substituted with halogen, OR 2  substituted with halogen, SR 2  substituted with halogen, NR 3  substituted with halogen, PR 3  substituted with halogen, NR 2 R′ substituted with halogen, PR 2 P′ substituted with halogen, ROR′ substituted with halogen, RSR′ substituted with halogen, C 2 -C 20  alkylidene substituted with halogen, C 2 -C 20  alkylidyne substituted with halogen, C 4 -C 20  cyclic alkylidene substituted with halogen, C 4 -C 20  diene substituted with halogen, C 6 -C 20  triene substituted with halogen, C 4 -C 20  cyclic diene substituted with halogen, C 2 -C 20  cyclic triene substituted with halogen, C 6 -C 20  arene substituted with halogen, C 2 -C 20  ether substituted with halogen, C 1 -C 20  amine substituted with halogen and C 3 -C 20  cyclic ether substituted with halogen, where R and R′ are individually selected from the group consisting of H, C 1 -C 10  alkyl and C 1 -C 10  alkyl substituted with halogen.  
     
     
         6 . The method according to  claim 1 , wherein the anion ligand X is selected from the group consisting of H, F, Cl, Br, I, C 1 -C 10  alkyl, C 2 -C 10  alkenyl, C 1 -C 8  alkoxy, C 6 -C 12  aryl, β-diketonate, cyclopentadienyl, C 1 -C 8  alkylcylcopentadienyl, C 1 -C 10  alkyl substituted with halogen, C 2 -C 10  alkenyl substituted with halogen, C 1 -C 8  alkoxy substituted with halogen, C 6 -C 12  aryl substituted with halogen, β-diketonate substituted with halogen, cyclopentadienyl substituted with halogen and C 1 -C 8  alkylcylcopentadienyl substituted with halogen.  
     
     
         7 . The method according to  claim 1 , wherein the metal precursor further comprises a neutral ligand in an amount ranging from 0.1 to 50 wt %.  
     
     
         8 . The method according to  claim 1 , wherein the metal precursor further comprises HX in an amount ranging from 0.1 to 50 wt % wherein X is an anion ligand.  
     
     
         9 . The method according to  claim 1 , wherein step (b) is performed at the presence of a catalyst selected from the group consisting of HF, HCl, HBr, HI, F 2 , Cl 2 , Br 2 , I 2 , C 1 -C 10  alkane substituted with halogen, C 2 -C 10  alkane substituted with halogen, C 1 -C 8  alkoxide substituted with halogen, C 6 -C 12  arene substituted with halogen, β-diketonate substituted with halogen, cyclopentadiene substituted with halogen and C 1 -C 8  alkylcyclopentadiene.  
     
     
         10 . The method according to  claim 1 , wherein parts (a) to (c) are performed using a CVD(chemical vapor deposition) method.  
     
     
         11 . A CVD method using a precursor M(L)X as a source, where M is a metal, L is a neutral ligand and X is an anion ligand, wherein the metal has an oxidation number of +1.  
     
     
         12 . The CVD method according to  claim 11 , the method being performed in the absence of oxygen or hydrogen as a reaction gas.