Rhodium film and method of formation

Abstract

A method for the formation of rhodium films with good step coverage is disclosed. Rhodium films are formed by a low temperature atomic layer deposition technique using a first gas of rhodium group metal precursor followed by an oxygen exposure. The invention provides, therefore, a method for forming smooth and continuous rhodium films which also have good step coverage and a reduced carbon content.

What is claimed as new and desired to be protected by Letters Patent of the United States is:  
     
         1 . A method for conducting atomic layer deposition of rhodium on a substrate comprising the steps of: 
 positioning said substrate in a deposition region of a reactor chamber;    introducing a rhodium group metal precursor into said reactor chamber to deposit a rhodium monolayer on said substrate; and    introducing oxygen into said deposition region to remove carbon from said rhodium monolayer.    
     
     
         2 . The method of  claim 1 , wherein said rhodium group metal precursor comprises an organic rhodium group metal precursor having the formula Ly[Rh]Yz, wherein L is independently selected from the group consisting of neutral and anionic ligands; y is one of {1, 2, 3, 4}; Y is independently a pi-orbital bonding ligand selected from the group consisting of CO, NO, CN, CS, N 2 , PX 3 , PR 3 , P(OR) 3 , AsX 3 , AsR 3 , As(OR) 3 , SbX 3 , SbR 3 , Sb(OR) 3 , NH x R 3−x , CNR, and RCN, wherein R is an organic group, X is a halide and x is one of {0, 1, 2, 3}; and z is one of {0, 1, 2, 3, 4}.  
     
     
         3 . The method of  claim 2 , wherein said rhodium group metal precursor is dicarbonyl cyclopentadienyl rhodium.  
     
     
         4 . The method of  claim 1 , wherein said atomic layer deposition is performed at a temperature of about 100° C. to about 200° C.  
     
     
         5 . The method of  claim 4 , wherein said atomic layer deposition is performed at a temperature of about 100° C. to about 150° C.  
     
     
         6 . The method of  claim 1 , wherein said rhodium group metal precursor is introduced into said reactor chamber at a rate of about 0.1 to about 500 sccm.  
     
     
         7 . The method of  claim 1 , wherein said rhodium group metal precursor is introduced into said reactor chamber at a rate of about 0.1 to about 5 sccm.  
     
     
         8 . The method of  claim 1 , wherein said oxygen is introduced into said reactor chamber at a rate of about 1 to about 500 sccm.  
     
     
         9 . The method of  claim 8 , wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 200 sccm.  
     
     
         10 . The method of  claim 1  further comprising introducing a first gas into said reactor chamber after said step of introducing said rhodium group metal precursor and before said step of introducing oxygen.  
     
     
         11 . The method of  claim 10 , wherein said first gas is selected from the group consisting of helium, argon and nitrogen.  
     
     
         12 . The method of  claim 10  further comprising introducing a second gas into said reactor chamber after said step of introducing oxygen.  
     
     
         13 . The method of  claim 12 , wherein said second gas is selected from the group consisting of helium, argon and nitrogen.  
     
     
         14 . A method for conducting atomic layer deposition of rhodium on an integrated circuit material layer, said method comprising the steps of: 
 positioning said material layer in a deposition region of a reactor chamber;    introducing dicarbonyl cyclopentadienyl rhodium into said deposition region of said reactor chamber to deposit a rhodium monolayer on said material layer at a temperature of about 100° C. to about 200° C.; and    introducing oxygen into said deposition region of said reactor chamber to remove carbon atoms from said rhodium monolayer.    
     
     
         15 . The method of  claim 14 , wherein said atomic layer deposition is performed at a temperature of about 100° C. to about 150° C.  
     
     
         16 . The method of  claim 15 , wherein said atomic layer deposition is performed at a temperature of about 100° C.  
     
     
         17 . The method of  claim 14 , wherein said dicarbonyl cyclopentadienyl rhodium is introduced into said reactor chamber at a rate of about 0.1 to about 500 sccm.  
     
     
         18 . The method of  claim 17 , wherein said dicarbonyl cyclopentadienyl rhodium is introduced into said reactor chamber at a rate of about 5 sccm.  
     
     
         19 . The method of  claim 14 , wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 500 sccm.  
     
     
         20 . The method of  claim 19 , wherein said oxygen is introduced into said reactor chamber at a rate of about 50 sccm.  
     
     
         21 . The method of  claim 14  further comprising introducing helium into said reactor chamber after said step of introducing said dicarbonyl cyclopentadienyl rhodium and before said step of introducing oxygen, at a rate of about 50 sccm and for about 5 seconds.  
     
     
         22 . The method of  claim 14  further comprising introducing helium into said reactor chamber after said step of introducing oxygen, at a rate of about 50 sccm and for about 5 seconds.  
     
     
         23 . A method for conducting atomic layer deposition of rhodium on an integrated circuit material layer at a temperature of about 100° C. to about 200° C., comprising the steps of: 
 positioning said material layer in a deposition region of a reactor chamber;  
 introducing dicarbonyl cyclopentadienyl rhodium into said reactor chamber at a rate of about 0.1 to about 500 sccm and for about 0.1 to about 30 seconds to deposit a rhodium monolayer on said material layer;  
 introducing a first purge gas at a rate of about 10 to about 200 sccm and for about 0.1 to about 10 seconds;  
 introducing oxygen into said deposition region at a rate of about 10 to about 200 sccm and for about 0.1 to about 10 seconds, and removing carbon atoms from said rhodium monolayer; and  
 introducing a second purge gas at a rate of about 10 to about 200 sccm and for about 0.1 to about 10 seconds.  
 
     
     
         24 . The method of  claim 23 , wherein said atomic layer deposition of rhodium is conducted at a temperature of about 100° C.  
     
     
         25 . The method of  claim 23 , wherein said dicarbonyl cyclopentadienyl rhodium is introduced into said reactor chamber at a rate of about 5 sccm and for about 5 seconds.  
     
     
         26 . The method of  claim 23 , wherein said oxygen is introduced into said reactor chamber at a rate of about 50 sccm and for about 5 seconds.  
     
     
         27 . The method of  claim 23 , wherein said first and said second purge gases are each introduced into said reactor chamber at a rate of about 50 sccm and for about 5 seconds.  
     
     
         28 . A method of forming a capacitor comprising the steps of: 
 forming a first and second electrode;    forming a dielectric layer between said first and second electrode; and    wherein at least one of said first and second electrode is formed by conducting atomic layer deposition of a rhodium group metal precursor.    
     
     
         29 . The method of  claim 28 , wherein said rhodium group metal precursor comprises an organic rhodium group metal precursor having the formula Ly[Rh]Yz, wherein L is independently selected from the group consisting of neutral and anionic ligands; y is one of {1, 2, 3, 4}; Y is independently a pi-orbital bonding ligand selected from the group consisting of CO, NO, CN, CS, N 2 , PX 3 , PR 3 , P(OR) 3 , AsX 3 , AsR 3 , As(OR) 3 , SbX 3 , SbR 3 , Sb(OR) 3 , NH x R 3−x , CNR, and RCN, wherein R is an organic group, X is a halide and x is one of {0, 1, 2, 3}; and z is one of {0, 1, 2, 3, 4}.  
     
     
         30 . The method of  claim 29 , wherein said rhodium group metal precursor is dicarbonyl cyclopentadienyl rhodium.  
     
     
         31 . The method of  claim 28 , wherein said atomic layer deposition is performed at a temperature of about 100° C. to about 200° C.  
     
     
         32 . The method of  claim 28 , wherein said rhodium group metal precursor is introduced into a reactor chamber at a rate of about 0.1 to about 500 sccm.  
     
     
         33 . The method of  claim 28 , wherein said rhodium group metal precursor is introduced into said reactor chamber at a rate of about 0.1 to about 5 sccm.  
     
     
         34 . The method of  claim 32  further comprising the step of introducing oxygen into said reactor chamber at a rate of about 10 to about 500 sccm.  
     
     
         35 . The method of  claim 34 , wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 200 sccm.  
     
     
         36 . The method of  claim 34  further comprising introducing a first gas into said reactor chamber after said step of introducing said rhodium group metal precursor and before said step of introducing oxygen.  
     
     
         37 . The method of  claim 36 , wherein said first gas is selected from the group consisting of helium, argon and nitrogen.  
     
     
         38 . The method of  claim 36  further comprising introducing a second gas into said reactor chamber after said step of introducing oxygen.  
     
     
         39 . The method of  claim 38 , wherein said second gas is selected from the group consisting of helium, argon and nitrogen.  
     
     
         40 . A method of forming a rhodium upper electrode of a capacitor in an insulating layer of a substrate, comprising the steps of: 
 forming a conductive layer;    forming a dielectric layer over said conductive layer; and    forming a rhodium layer by atomic layer deposition at a temperature of about 100° C. to about 200° C. over said dielectric layer.    
     
     
         41 . The method of  claim 40 , wherein said step of forming said rhodium layer by atomic layer deposition comprises introducing said substrate in a deposition region of a reactor chamber, and introducing dicarbonyl cyclopentadienyl rhodium into said reactor chamber.  
     
     
         42 . The method of  claim 41 , wherein said dicarbonyl cyclopentadienyl rhodium is introduced at a rate of about 0.1 sccm to about 500 sccm.  
     
     
         43 . The method of  claim 41 , wherein said dicarbonyl cyclopentadienyl rhodium is introduced into said reactor chamber at a rate of about 0.1 sccm to about 5 sccm.  
     
     
         44 . The method of  claim 41 , wherein said step of forming said rhodium layer by atomic layer deposition further comprises introducing oxygen into said reactor chamber.  
     
     
         45 . The method of  claim 44 , wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 500 sccm.  
     
     
         46 . The method of  claim 44 , wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 200 sccm.  
     
     
         47 . A method of forming a rhodium lower electrode of a capacitor in an insulating layer of a substrate, comprising the steps of: 
 forming a rhodium layer by atomic layer deposition at a temperature of about 100° C. to about 200° C.;    forming a dielectric layer over said rhodium layer; and    forming a conductive layer over said dielectric layer.    
     
     
         48 . The method of  claim 47 , wherein said step of forming said rhodium layer by atomic layer deposition comprises introducing said substrate in a deposition region of a reactor chamber, and introducing dicarbonyl cyclopentadienyl rhodium into said reactor chamber.  
     
     
         49 . The method of  claim 48 , wherein said dicarbonyl cyclopentadienyl rhodium is introduced at a rate of about 0.1 sccm to about 500 sccm.  
     
     
         50 . The method of  claim 49 , wherein said dicarbonyl cyclopentadienyl rhodium is introduced into said reactor chamber at a rate of about 0.1 sccm to about 5 sccm.  
     
     
         51 . The method of  claim 48 , wherein said step of forming said rhodium layer by atomic layer deposition further comprises introducing introducing oxygen into said reactor chamber.  
     
     
         52 . The method of  claim 51 , wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 500 sccm.  
     
     
         53 . The method of  claim 52 , wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 200 sccm.  
     
     
         54 . A method of fabricating a DRAM cell container capacitor comprising the steps of: 
 forming a first and second conductive layer; and    forming a dielectric between said first and second conductive layer, at least one of said first and second conductive layer being a rhodium layer formed by atomic layer deposition of dicarbonyl cyclopentadienyl rhodium at a temperature of about 100° C. to about 200° C. and for about 5 seconds.    
     
     
         55 . A capacitor comprising: 
 a first electrode and a second electrode;    a dielectric provided between said first electrode and said second electrode; and    at least one of said first and second electrode comprising a continuous ALD deposited rhodium film with reduced carbon content.    
     
     
         56 . A capacitor comprising: 
 a first electrode and a second electrode;    a dielectric provided between said first electrode and said second electrode; and    at least one of said first and second electrode comprising a reduced-carbon rhodium film formed by rhodium atomic layer deposition at a temperature of about 100° C. to about 200° C.