Semiconductor Device Having Multiple Work Functions and Method of Manufacture Therefor

Abstract

The present invention provides a semiconductor device, a method of manufacture therefor, and a method for manufacturing an integrated circuit. The semiconductor device ( 100 ), among other possible elements, includes a first transistor ( 120 ) located over a semiconductor substrate ( 110 ), wherein the first transistor ( 120 ) has a metal gate electrode ( 135 ) having a work function, and a second transistor ( 160 ) located over the semiconductor substrate ( 110 ) and proximate the first transistor ( 120 ), wherein the second transistor ( 160 ) has a plasma altered metal gate electrode ( 175 ) having a different work function.

1 . A semiconductor device, comprising: 
 a first transistor located over a semiconductor substrate, wherein the first transistor has a metal gate electrode having a work function; and    a second transistor located over the semiconductor substrate and proximate the first transistor, wherein the second transistor has a plasma altered metal gate electrode having a different work function.    
   
   
       2 . The semiconductor device as recited in  claim 1  wherein the first transistor is an N-channel metal oxide semiconductor device and the second transistor is a P-channel metal oxide semiconductor device.  
   
   
       3 . The semiconductor device as recited in  claim 1  wherein the metal gate electrode is a metal and the plasma altered metal gate electrode includes the metal.  
   
   
       4 . The semiconductor device as recited in  claim 1  wherein the plasma altered metal gate electrode is a plasma nitrided metal gate electrode.  
   
   
       5 . The semiconductor device as recited in  claim 1  wherein the plasma altered metal gate electrode is a plasma silicided metal gate electrode.  
   
   
       6 . The semiconductor device as recited in  claim 5  wherein the metal comprises a material selected from the group consisting of cobalt, titanium, nickel and palladium.  
   
   
       7 . The semiconductor device as recited in  claim 1  wherein the plasma altered metal gate electrode is a plasma germanided metal gate electrode.  
   
   
       8 . The semiconductor device as recited in  claim 1  wherein the plasma altered metal gate electrode is a plasma oxidized metal gate electrode.  
   
   
       9 . The semiconductor device as recited in  claim 8  wherein the metal comprises a material selected from the group consisting of ruthenium, iridium, osmium, indium and tin.  
   
   
       10 . The semiconductor device as recited in  claim 1  further including a cladding layer located over the metal gate electrode and the plasma altered metal gate electrode, the cladding layer configured to reduce a sheet resistance of the first and second transistors.  
   
   
       11 . The semiconductor device as recited in  claim 10  wherein the cladding layer is selected from the group of materials consisting of polysilicon, molybdenum, tungsten, and titanium nitride.