Gas nozzle for substrate processing chamber

Abstract

A gas delivery nozzle for a substrate fabrication apparatus has a gas delivery tube. The gas delivery tube encloses a gas channel having an asymmetrically tapered aperture. The asymmetrically tapered aperture is defined by (i) a lower lip that projects upwardly into the gas channel to partially block the gas channel and (ii) a upper brim that projects downwardly into the gas channel and overhangs the lower lip.

We claim:  
     
         1 . A gas delivery nozzle for a substrate fabrication apparatus, the gas delivery nozzle comprising: 
 a gas delivery tube enclosing a gas channel having an asymmetrically tapered aperture defined by: 
 (i) a lower lip that projects upwardly into the gas channel to partially block the gas channel, and  
 (ii) a upper brim that projects downwardly into the gas channel and overhangs the lower lip.  
   
     
     
         2 . The gas delivery nozzle of  claim 1  wherein the lower lip comprises an external slanted face that is at an angle of at least about 5° in relation to a central axis of the gas delivery tube along the gas channel.  
     
     
         3 . The gas delivery nozzle of  claim 2  wherein the external slanted face is at an angle of less than 90°.  
     
     
         4 . The gas delivery nozzle of  claim 1  wherein the upper brim extends beyond the lower lip by at least about 1 mm.  
     
     
         5 . The gas delivery nozzle of  claim 1  wherein the asymmetrically tapered aperture comprises a center that is offset below the central axis of the gas delivery tube.  
     
     
         6 . The gas delivery nozzle of  claim 1  wherein the lower lip comprises a protuberance having a crescent shape.  
     
     
         7 . A substrate fabrication apparatus comprising: 
 a chamber having a substrate support to support a substrate in the chamber;    a gas distributor to introduce a process gas into the chamber, the gas distributor comprising a gas delivery nozzle in the chamber, the gas delivery nozzle comprising a gas delivery tube that encloses a gas channel having an asymmetrically tapered aperture, the asymmetrically tapered aperture defined by:    (i) a lower lip that projects upwardly into the gas channel to partially block the gas channel, and    (ii) a upper brim that projects downwardly into the gas channel and overhangs the lower lip;    a gas energizer to energize the process gas to process the substrate; and    a gas exhaust to exhaust the process gas from the chamber.    
     
     
         8 . The apparatus of  claim 7  wherein the lower lip comprises an external slanted face that is at an angle of at least about 5° in relation to a central axis of the gas delivery tube along the gas channel.  
     
     
         9 . The apparatus of  claim 8  wherein the external slanted face is at an angle of less than 90°.  
     
     
         10 . The apparatus of  claim 7  wherein the upper brim extends beyond the lower lip by at least about 1 mm.  
     
     
         11 . The apparatus of  claim 7  wherein the asymmetrically tapered aperture comprises a center that is offset below the central axis of the gas delivery tube.  
     
     
         12 . The apparatus of  claim 7  wherein the lower lip comprises a protuberance having a crescent shape.