Dry clean method instead of traditional wet clean after metal etch

Abstract

A dry cleaning method for use in semiconductor fabrication, including the following steps. An etched metallization structure is provided and placed in a processing chamber. The etched metallization structure is cleaned by introducing a fluorine containing gas/oxygen containing gas mixture into the processing chamber proximate the etched metallization structure without the use of a downstream microwave while applying a magnetic field proximate the etched metallization structure and maintaining a pressure of less than about 50 millitorr within the processing chamber for a predetermined time.

We claim:  
     
         1 . A dry cleaning method for use in semiconductor fabrication, including the steps of: 
 providing an etched metallization structure;    placing said etched metallization structure in a processing chamber; and    cleaning said etched metallization structure by introducing a fluorine containing gas/oxygen containing gas mixture into said processing chamber proximate said etched metallization structure without the use of a downstream microwave while applying a magnetic field proximate said etched metallization structure and maintaining a pressure of less than about 50 millitorr within said processing chamber for a predetermined time.    
     
     
         2 . The method of  claim 1 , further including the step of then rinsing said etched metallization structure with deionized water.  
     
     
         3 . The method of  claim 1 , further including the step of rinsing said etched metallization structure with deionized water at a megasonic power from about 0 to 500W.  
     
     
         4 . The method of  claim 1 , wherein said etched metallization structure includes an upper barrier layer, bulk Al-0.5% Cu alloy, and a bottom barrier layer.  
     
     
         5 . The method of  claim 1 , wherein said fluorine containing gas/oxygen containing gas mixture has a fluorine containing gas:oxygen containing gas ratio of about 1:4; said magnetic field is greater than about 10 gauss; said pressure is from about 10 to 50 millitorr, and said predetermined time is from about 28 to 32 seconds.  
     
     
         6 . The method of  claim 1 , wherein said fluorine containing gas/oxygen containing gas mixture has a fluorine containing gas:oxygen containing gas ratio of about 1:4; said magnetic field is from about 20 to 100 gauss; said pressure is about 20 millitorr, and said predetermined time is about 30 seconds.  
     
     
         7 . The method of  claim 1 , wherein said cleaning step includes maintaining an RF power of greater than about 200 W; said magnetic field is from about 20 to 100 gauss at a radio frequency of about 13.56 MHz; and said predetermined time is from about 10 to 60 seconds.  
     
     
         8 . The method of  claim 1 , wherein said cleaning step includes maintaining an RF power of from about 200 to 500 W; said magnetic field is from about 20 to 100 gauss at a radio frequency of about 13.56 MHz; and said predetermined time is from about 28 to 32 seconds.  
     
     
         9 . The method of  claim 1 , wherein said cleaning step includes maintaining an RF power of about 300 W; said magnetic field is about 20 gauss at a radio frequency of about 13.56 MHz; and said predetermined time is about 30 seconds.  
     
     
         10 . A dry cleaning method for use in semiconductor fabrication, including the steps of: 
 providing an etched metallization structure;    placing said etched metallization structure in a processing chamber;    cleaning said etched metallization structure by introducing a fluorine containing gas/oxygen containing gas mixture into said processing chamber proximate said etched metallization structure without the use of a downstream microwave while applying a magnetic field proximate said etched metallization structure and maintaining a pressure of less than about 50 millitorr within said processing chamber for a predetermined time; and    rinsing said etched metallization structure with deionized water.    
     
     
         11 . The method of  claim 10 , wherein said deionized water rinsing step is conducted at a megasonic power from about 250 to 350.  
     
     
         12 . The method of  claim 10 , wherein said etched metallization structure includes an upper barrier layer, bulk Al-0.5% Cu alloy, and a bottom barrier layer.  
     
     
         13 . The method of  claim 10 , wherein said fluorine containing gas/oxygen containing gas mixture has a fluorine containing gas:oxygen containing gas ratio of about 1:4; said magnetic field is greater than about 10 gauss; said pressure is from about 10 to 50 millitorr, and said predetermined time is from about 28 to 32 seconds.  
     
     
         14 . The method of  claim 10 , wherein said fluorine containing gas/oxygen containing gas mixture has a fluorine containing gas:oxygen containing gas ratio of about 1:4; said magnetic field is from about 20 to 100 gauss; said pressure is about 20 millitorr, and said predetermined time is about 30 seconds.  
     
     
         15 . The method of  claim 10 , wherein said cleaning step includes maintaining an RF power of greater than about 200 W; said magnetic field is greater than about 10 gauss at a radio frequency of about 13.56 MHz; and said predetermined time is from about 10 to 60 seconds.  
     
     
         16 . The method of  claim 10 , wherein said cleaning step includes maintaining an RF power of from about 200 to 500 W; said magnetic field is from about 20 to 100 gauss at a radio frequency of about 13.56 MHz; and said predetermined time is from about 28 to 32 seconds.  
     
     
         17 . The method of  claim 10 , wherein said cleaning step includes maintaining an RF power of about 300 W; said magnetic field is about 20 gauss at a radio frequency of about 13.56 MHz; and said predetermined time is about 30 seconds.  
     
     
         18 . A dry cleaning method for use in semiconductor fabrication, including the steps of: 
 providing an aluminum alloy layer over a substrate and a resist layer over said aluminum alloy layer;    reactive ion etching said aluminum alloy layer using a Cl-containing plasma to form a patterned aluminum alloy layer with a polymer on a sidewall of said patterned aluminum alloy layer;    placing said substrate in a processing chamber; and    removing said resist and said polymer and cleaning said patterned aluminum alloy layer by introducing a fluorine containing gas/oxygen containing gas mixture into said processing chamber proximate said etched metallization structure without the use of a downstream microwave while applying a magnetic field of greater than about 10 gauss at a radio frequency of about 13.56 MHz proximate said etched metallization structure at an RF power greater than about 200 W, and maintaining a pressure of less than about 50 millitorr within said processing chamber for from about 28 to 32 seconds.    
     
     
         19 . The method of  claim 18 , wherein said deionized water rinsing step is conducted at a megasonic power from about 250 to 350.  
     
     
         20 . The method of  claim 18 , wherein said patterned aluminum alloy layer includes an upper barrier layer, bulk Al-0.5% Cu alloy, and a bottom barrier layer.  
     
     
         21 . The method of  claim 18 , wherein said fluorine containing gas/oxygen containing gas mixture has a fluorine containing gas:oxygen containing gas ratio of about 1:4; said magnetic field is from about 20 to 100 gauss at a radio frequency of about 13.56 MHz; said RF power is from about 200 to 500 W, said pressure is from about 10 to 50 millitorr, and said predetermined time is from about 28 to 32 seconds.  
     
     
         22 . The method of  claim 18 , wherein said fluorine containing gas/oxygen containing gas mixture has a fluorine containing gas:oxygen containing gas ratio of about 1:4; said magnetic field is about 20 gauss at a radio frequency of about 13.56 MHz; said RF power is about 300 W, said pressure is about 20 millitorr, and said predetermined time is about 30 seconds.  
     
     
         23 . The method of  claim 18  including the step of rinsing said patterned aluminum alloy layer with deionized water with a megasonic power from about 250 to 350 W.