Plasma treatment of tantalum nitride compound films formed by chemical vapor deposition

Abstract

A method of forming tantalum nitride (TaN) compound layers for use in integrated circuit fabrication processes is disclosed. The tantalum nitride (TaN) compound layer is formed by thermally decomposing a tantalum containing metal organic precursor. After the tantalum nitride (TaN) compound layer is formed, it is plasma treated.

What is claimed is:  
     
         1 . A method of forming a device, comprising: 
 (a) providing a substrate having a dielectric layer thereon, wherein the dielectric layer has vias therein;    (b) forming a tantalum nitride (TaN) compound layer on the dielectric layer;    (c) plasma treating the tantalum nitride (TaN) compound layer;    (d) exposing the plasma treated tantalum nitride (TaN) compound layer to a silane (SiH 4 ) based atmosphere; and    (f) filling the vias with a conductive material.    
     
     
         2 . The method of  claim 1  wherein the conductive material filling the vias has a resistivity less than about 10 μΩ-cm (microohms-centimeters).  
     
     
         3 . The method of  claim 1  wherein the dielectric layer is selected from the group of silicon dioxide, fluorosilicate glass (FSG), undoped silicate glass (USG), and combinations thereof.  
     
     
         4 . The method of  claim 1  wherein the conductive material filling the vias is selected from the group of copper (Cu), aluminum (Al), tungsten (W), and combinations thereof.  
     
     
         5 . The method of  claim 1  wherein step (b), comprises: 
 positioning the substrate in a deposition chamber;  
 providing a gas mixture to the deposition chamber wherein the gas mixture comprises a tantalum (Ta) containing metal organic precursor; and  
 thermally decomposing the Ta containing metal organic precursor to form a tantalum nitride (TaN) compound layer on the substrate.  
 
     
     
         6 . The method of  claim 5  wherein the gas mixture further comprises a carrier gas.  
     
     
         7 . The method of  claim 6  wherein the carrier gas is selected from the group of hydrogen (H 2 ), argon (Ar), helium (He), nitrogen (N 2 ), and combinations thereof.  
     
     
         8 . The method of  claim 5  wherein the Ta containing metal organic precursor is selected from the group of pentakis(diethylamido) tantalum (PDEAT) (Ta(NEt 2 ) 5 ), pentakis(ethylmethylamido) tantalum (PEMAT) (Ta(N(Et)(Me)) 5 ), pentakis(dimethylamido) tantalum (PDMAT) (Ta(NMe 2 ) 5 ), tetrakis(ethylmethylamido) tantalum (TEMAT) (Ta(N(Et)(Me)) 4 ), tetrakis(diethylamido) tantalum (TDEAT) (Ta(NEt 2 ) 4 ), tetrakis(dimethylamido) tantalum (TDMAT) (Ta(NMe 2 ) 4 ), and combinations thereof.  
     
     
         9 . The method of  claim 5  wherein the substrate is heated to a temperature of between about 200° C. to about 600° C.  
     
     
         10 . The method of  claim 5  wherein the deposition chamber is maintained at a pressure between about 0.1 torr to about 100 torr.  
     
     
         11 . The method of  claim 5  wherein the tantalum containing metal organic precursor is provided to the deposition chamber at a flow rate in a range of about 0.1 sccm to about 1,000 sccm.  
     
     
         12 . The method of  claim 6  wherein the carrier gas is provided to the deposition chamber at a flow rate in a range of about 10 sccm to about 10,000 sccm.  
     
     
         13 . The method of  claim 1  wherein the plasma of step (c) is generated by 
 providing a gas mixture to a process chamber; and  
 applying an electric field to the gas mixture in the process chamber to generate the plasma.  
 
     
     
         14 . The method of  claim 13  wherein the gas mixture comprises one or more gases selected from the group of molecular hydrogen (H 2 ), argon (Ar), helium (He), nitrogen (N 2 ), and combinations thereof.  
     
     
         15 . The method of  claim 13  wherein the process chamber is maintained at a pressure in a range of about 0.1 torr to about 100 torr.  
     
     
         16 . The method of  claim 13  the gas mixture is provided to the deposition chamber at a flow rate in a range of about 10 sccm to about 10,000 sccm.  
     
     
         17 . The method of  claim 13  wherein the electric field is a radio frequency (RF) power.  
     
     
         18 . The method of  claim 17  wherein the RF power is in a range of about 50 watts to about 2,000 watts.  
     
     
         19 . The method of  claim 13  wherein the plasma is generated in a process chamber used for tantalum nitride (TaN) compound layer deposition.  
     
     
         20 . The method of  claim 13  wherein the plasma is generated in a process chamber that is coupled to a process chamber used for tantalum nitride (TaN) compound layer deposition.  
     
     
         21 . The method of  claim 1  wherein step (c) comprises: 
 plasma treating the tantalum nitride (TaN) compound layer using an argon (Ar) based plasma.  
 
     
     
         22 . A method of forming a device comprising: 
 (a) providing a substrate having a dielectric layer thereon, wherein the dielectric layer has vias therein;    (b) forming a tantalum nitride (TaN) compound layer on the dielectric layer from a Ta containing metal organic precursor;    (c) plasma treating the tantalum nitride (TaN) compound layer;    (d) exposing the plasma treated tantalum nitride (TaN) compound layer to a silane (SiH 4 ) based atmosphere; and    (e) filling the vias with a conductive material.    
     
     
         23 . The method of  claim 22  wherein the Ta containing metal organic precursor is selected from the group of pentakis(diethylamido) tantalum (PDEAT) (Ta(NEt 2 ) 5 ), pentakis(ethylmaethylamido) tantalum (PEMAT) (Ta(N(Et)(Me)) 5 ), pentakis(dimethylamido) tantalum (PDMAT) (Ta(NMe 2 ) 5 ), tetrakis(ethylmethylamido) tantalum (TEMAT) (Ta(N(Et)(Me)) 4 ), tetrakis(diethylamido) tantalum (TDEAT) (Ta(NEt 2 ) 4 ), tetrakis(dimethylamido) tantalum (TDMAT) (Ta(NMe 2 ) 4 ), and combinations thereof.  
     
     
         24 . The method of  claim 22  wherein the substrate is heated to a temperature between 200° C. to about 600° C.  
     
     
         25 . The method of  claim 22  wherein the tantalum nitride (TaN) compound layer is formed at a pressure between about 0.1 torr to about 100 torr.  
     
     
         26 . The method of  claim 22  wherein the tantalum nitride (TaN) compound layer is plasma treated in the presence of one or more gases selected from the group consisting of molecular hydrogen (H 2 ), argon (Ar), helium (He), and nitrogen (N 2 ).  
     
     
         27 . A method of forming a device, comprising: 
 (a) providing a substrate having a dielectric layer thereon, wherein the dielectric layer has vias therein;    (b) forming a tantalum nitride compound layer on the substrate from a Ta containing metal organic precursor;    (c) plasma treating the tantalum nitride (TaN) compound layer in the presence of one or more gases selected from the group consisting of molecular hydrogen (H 2 ), argon (Ar), helium (He) and nitrogen (N 2 );    (d) exposing the plasma treated tantalum nitride (TaN) compound layer to a silane (SiH 4 ) based atmosphere; and    (e) filling the vias with a conductive material.    
     
     
         28 . The method of  claim 27  wherein the Ta containing metal organic precursor is selected from the group of pentakis(diethylamido) tantalum (PDEAT) (Ta(NEt 2 ) 5 ), pentakis(ethylmethylamido) tantalum (PEMAT) (Ta(N(Et)(Me)) 5 ), pentakis(dimethylamido) tantalum (PDMAT) (Ta(NMe 2 ) 5 ), tetrakis(ethylmethylamido) tantalum (TEMAT (Ta(N(Et)(Me)) 4 ), tetrakis(diethylamido) tantalum (TDEAT) (Ta(NEt 2 ) 4 ), tetrakis(dimethylamido) tantalum (TDMAT) (Ta(NMe 2 ) 4 ), and combinations thereof.  
     
     
         29 . The method of  claim 27  wherein the substrate is heated to a temperature between 200° C. to about 600° C.  
     
     
         30 . The method of  claim 27  wherein the tantalum nitride (TaN) compound layer is formed at a pressure between about 0.1 torr to about 100 torr.  
     
     
         31 . The method of  claim 27  wherein the tantalum nitride (TaN) compound layer is plasma treated in the presence of argon.  
     
     
         32 . The method of  claim 27  wherein the tantalum nitride (TaN) compound layer is plasma treated in the presence of molecular hydrogen (H 2 ).