Apparatus and method for plasma enhanced monolayer processing

Abstract

An apparatus and method for plasma enhanced monolayer (PEM) processing, wherein excited species from a non-condensable gas plasma are delivered to a substrate surface during the reaction of a chemical precursor with a previously chemisorbed monolayer on the substrate surface; the excited species lower the activation energy of the monolayer formation reaction and also modulate the film properties. In preferred embodiments a process reactor has linear injectors arranged diametrically above a substrate and reactive gases are sequentially injected onto the substrate surface while it is being rotated. The reactor can be operated in pulse precursor and pulsed plasma, constant precursor and constant plasma modes, or a combination thereof.

What is claimed is:  
     
         1 . An apparatus for plasma enhanced monolayer deposition on a substrate, comprising: 
 a reaction chamber;    a platen contained within said reaction chamber, said substrate being positioned on the top surface of said platen during deposition;    at least two injectors positioned within said reaction chamber proximate to the top surface of said platen; and    a plasma generator contained at least partially within said reaction chamber;    wherein said injectors are configured to deliver gas to the upper surface of said substrate and wherein said plasma generator and said injectors are configured together to generate and deliver plasma species to the upper surface of said substrate.    
     
     
         2 . The apparatus of  claim 1 , wherein said platen is rotatable.  
     
     
         3 . The apparatus of  claim 1 , wherein said platen is generally circular and wherein said injectors are linear injectors positioned diametrically above said platen.  
     
     
         4 . The apparatus of  claim 1 , wherein said injectors are linear injectors with a plurality of outlets distributed longitudinally.  
     
     
         5 . The apparatus of  claim 1 , wherein said plasma generator comprises: 
 a plasma power source; and    plasma electrodes coupled to said plasma power source, said electrodes being contained within said reaction chamber.    
     
     
         6 . The apparatus of  claim 5 , wherein said plasma electrodes are proximate and parallel to the top surface of said platen.  
     
     
         7 . The apparatus of  claim 5 , wherein said plasma electrodes are positioned around one of said injectors.  
     
     
         8 . The apparatus of  claim 5 , wherein said plasma electrodes are positioned within one of said injectors.  
     
     
         9 . The apparatus of  claim 5 , wherein said plasma electrodes are configured to form a cavity containing one of said injectors.  
     
     
         10 . The apparatus of  claim 5 , wherein said plasma electrodes are configured to form a cavity containing a gas inlet, said gas inlet being attached to one of said injectors.  
     
     
         11 . The apparatus of  claim 1 , further comprising a substrate heater configured to heat said substrate during deposition.  
     
     
         12 . The apparatus of  claim 1 , further comprising a DC power supply coupled to said platen, said DC power supply being configured to maintain said substrate at a predetermined bias voltage during deposition, wherein said substrate is electrically coupled to said platen.  
     
     
         13 . The apparatus of  claim 1 , further comprising a vacuum pump coupled to said reaction chamber, said vacuum pump and said reaction chamber being configured together to minimize the residence time of deposition gases within said reaction chamber without increasing the time required to form a chemisorbed monolayer of precursor gas on the surface of said substrate.  
     
     
         14 . The apparatus of  claim 1 , further comprising three gas source units coupled to said injectors.  
     
     
         15 . The apparatus as in  claim 14 , wherein said gas source units comprise a first chemical precursor unit, a second chemical precursor unit and a non-condensable gas source unit.  
     
     
         16 . The apparatus of  claim 14 , wherein two of said gas source units are coupled to one of said injectors.  
     
     
         17 . The apparatus of  claim 14 , wherein each of said gas source units is coupled to a different one of said injectors.  
     
     
         18 . The apparatus of  claim 1 , wherein said platen accommodates multiple substrates.  
     
     
         19 . The apparatus of  claim 18 , wherein said multiple substrates include substrates of different shapes.  
     
     
         20 . The apparatus of  claim 18 , wherein said multiple substrates include substrates of different sizes.  
     
     
         21 . An apparatus for plasma enhanced monolayer deposition on a substrate, comprising: 
 a reaction chamber;    a vacuum pump coupled to said reaction chamber;    a platen contained within said reaction chamber, said substrate being positioned on the top surface of said platen during deposition;    three linear injectors positioned within said reaction chamber proximate and parallel to the top surface of said platen;    three gas source units, each gas source unit coupled to a different one of said linear injectors; and    a plasma generator contained at least partially within said reaction chamber.    
     
     
         22 . An apparatus as in  claim 21 , wherein said plasma generator is coupled to one of said linear injectors.  
     
     
         23 . A method for plasma enhanced monolayer deposition on a substrate, comprising: 
 delivering a gaseous first chemical precursor on the surface of said substrate for chemisorption;    delivering a gaseous second chemical precursor for reaction with said chemisorbed first chemical precursor; and    simultaneously with said reaction step, providing reactive species of non-condensable gas plasma to said substrate surface;    wherein said first chemical precursor and said second chemical precursor are provided through injectors positioned proximate to the surface of said substrate.    
     
     
         24 . The method as in  claim 23 , further comprising continuously rotating said substrate during said deposition.  
     
     
         25 . The method as in  claim 23 , further comprising the step of purging excess first chemical precursor from the surface of said substrate.  
     
     
         26 . The method as in  claim 25 , wherein said purging step occurs after said chemisorption step.  
     
     
         27 . The method as in  claim 25 , wherein said purging step occurs before said reaction step.  
     
     
         28 . The method as in  claim 25 , wherein said purging step utilizes a non-condensable gas.  
     
     
         29 . The method as in  claim 23 , further comprising purging excess second chemical precursor from the surface of said substrate.  
     
     
         30 . The method as in  claim 29 , wherein said purging step occurs after said reaction step.  
     
     
         31 . The method as in  claim 23 , wherein said providing step includes generating pulsed plasma.  
     
     
         32 . The method as in  claim 23 , wherein said substrate is positioned on a platen and wherein said injectors are linear and configured parallel to the surface of said platen.  
     
     
         33 . The method as in  claim 32 , wherein said platen is generally circular and wherein said injectors are positioned diametrically with respect to said platen.  
     
     
         34 . The method as in  claim 33 , further including the step of rotating said platen, wherein one deposition cycle includes two complete rotations of said platen.  
     
     
         35 . The method as in  claim 23 , wherein said active species are provided through one of said injectors positioned proximate to the surface of said substrate.  
     
     
         36  The method as in  claim 23 , wherein said active species are provided through a further injector positioned proximate to the surface of said substrate.