Plasma RIE polymer removal

Abstract

A method for removal of post reactive ion etch by-product from a semiconductor wafer surface or microelectronic composite structure comprising: supplying a reducing gas plasma incorporating a forming gas mixture selected from the group consisting of a mixture of N 2 /H 2 or a mixture of NH 3 /H 2 into a vacuum chamber in which a semiconductor wafer surface or a microelectronic composite structure is supported to form a post-RIE polymer material by-product on the composite structure without significant removal of an organic, low K material which has also been exposed to the reducing gas plasma; and removing the post-RIE polymer material by-product with a wet clean.

We claim:  
     
         1 . A method for removal of post reactive ion etch by-product from a semiconductor wafer surface or microelectronic composite structure comprising: 
 supplying a reducing gas plasma incorporating a forming gas mixture selected from the group consisting of a mixture of N 2 /H 2  or a mixture of NH 3 /H 2  into a vacuum chamber in which a semiconductor wafer surface or a microelectronic composite structure is supported to form a post-RIE polymer material by-product on the composite structure without significant removal of an organic, low K material which has also been exposed to said reducing gas plasma; and    removing said post-RIE polymer material by-product with a wet clean.    
     
     
         2 . The method of  claim 1  wherein said reducing gas plasma incorporating a forming gas mixture is a mixture of N 2 /H 2 .  
     
     
         3 . The method of  claim 1  wherein said reducing gas plasma incorporating a forming gas mixture is a mixture of NH 3 /H 2 .  
     
     
         4 . The method of  claim 1  wherein said composite structure is a Via structure.  
     
     
         5 . The method of  claim 1  wherein said semiconductor wafer surface is a dual damascene structure.  
     
     
         6 . The method of  claim 4  wherein said Via structure is a single damascene structure.  
     
     
         7 . The method of  claim 1  wherein said post-RIE polymer material byproduct is a fluoropolymer/hydrocarbon material.  
     
     
         8 . The method of  claim 7  wherein removal of said organic low K material is in an amount less than 200 Å.  
     
     
         9 . A semiconductor wafer surface characterized by less than 200 Å of removal of organic low K material after removal of post reactive ion etch by-product with a reducing gas plasma that incorporates a forming gas mixture selected from the group consisting of a mixture of N 2 /H 2  or a mixture of NH 3 /H 2 .