Waferless automatic cleaning after barrier removal

Abstract

A method for forming features in dielectric layers and opening barrier layers for a plurality of wafers and cleaning an etch chamber after processing and removing each wafer of the plurality of wafers is provided. A wafer of the plurality of wafers is placed into the etch chamber wherein the wafer has a barrier layer over the wafer and a dielectric layer over the barrier layer. The dielectric layer is etched. The barrier layer is opened. The wafer is removed from the etch chamber. A waferless automatic cleaning of the etch chamber without the wafer is provided. The waferless automatic cleaning comprises providing a waferless automatic cleaning gas comprising oxygen and nitrogen to the etch chamber and forming a waferless automatic cleaning plasma from the waferless automatic cleaning gas to clean the etch chamber.

1 . An apparatus for etching features in dielectric layers and opening barrier layers for a plurality of wafers, comprising: 
 an etch chamber;    an upper electrode with the etch chamber;    a lower electrode with the etch chamber;    an RF source electrically connected to at least one of the upper electrode and lower electrode;    a gas source in fluid connection with the etch chamber to provide gas into the etch chamber; and    a controller controllably connected to the RF source and the gas source comprising computer readable media, comprising: 
 computer readable code for etching the dielectric layer;  
 computer readable code for opening a barrier layer; and  
 computer readable code for providing a waferless automatic cleaning of the etch chamber after a wafer has been removed from the etch chamber to empty the etch chamber after the opening of a barrier layer, comprising:  
 computer readable code for providing a waferless automatic cleaning gas comprising oxygen and nitrogen to the etch chamber; and  
 computer readable code for forming a waferless automatic cleaning plasma from the waferless automatic cleaning gas to clean the etch chamber.  
   
   
   
       2 . The apparatus, as recited in  claim 1 , wherein the computer readable code for providing the waferless automatic cleaning gas provides the waferless automatic cleaning gas with an oxygen to nitrogen flow ratio between 1:99 to 2:98.  
   
   
       3 . The apparatus, as recited in  claim 1 , wherein the computer code for providing the waferless automatically cleaning gas provides a waferless automatic cleaning gas consisting essentially of oxygen and nitrogen.  
   
   
       4 . The apparatus, as recited in  claim 1 , further comprising computer code for cleaning the etch chamber after processing and removing each wafer of the plurality of wafers.  
   
   
       5 . The apparatus, as recited in  claim 1 , wherein the barrier layer is selected from the group of SiN and SiC.  
   
   
       6 . The apparatus, as recited in  claim 1 , further comprising computer code for providing waferless automatic cleaning each time a wafer of the plurality of wafers is removed from the etch chamber to empty the etch chamber after the barrier layer opening.  
   
   
       7 . The apparatus, as recited in  claim 6 , wherein the waferless automatic cleaning is able to clean both the upper electrode and the lower electrode.  
   
   
       8 . The apparatus, as recited in  claim 1 , wherein the forming the waferless automatic cleaning plasma comprises providing more than 300 watts at a frequency between 12-50 MHz.  
   
   
       9 . The apparatus, as recited in  claim 1 , wherein the forming the waferless automatic cleaning plasma comprises maintaining a chamber pressure between 500-750 mTorr.  
   
   
       10 . The apparatus, as recited in  claim 1 , wherein the barrier layer is SiN.