Thermal control of deposition in dip pen nanolithography

Abstract

The present invention describes an apparatus for nanolithography and a process for thermally controlling the deposition of a solid organic “ink” from the tip of an atomic force microscope to a substrate. The invention may be used to turn deposition of the ink to the substrate on or off by either raising its temperature above or lowing its temperature below the ink's melting temperature. This process may be useful as it allows ink deposition to be turned on and off and the deposition rate to change without the tip breaking contact with the substrate. The same tip can then be used for imaging purposes without fear of contamination. This invention can allow ink to be deposited in a vacuum enclosure, and can also allow for greater spatial resolution as the inks used have lower surface mobilities once cooled than those used in other nanolithography methods.

1 . A thermal control apparatus comprising:
 a scanning probe microscope tip capable of being coated with at least one patterning compound; and   a temperature control device, operatively connected to the tip, wherein the temperature control device alters the temperature of the patterning compound more than the average temperature of the environment of the tip.   
     
     
         2 . The apparatus of  claim 1 , wherein the temperature control device causes the patterning compound to transition between immobile and mobile 
     
     
         3 . The apparatus of  claim 1 ,
 wherein the tip is in a gas-filled chamber; and   wherein the temperature control device alters the temperature of the patterning compound more than the average temperature of the gas in the chamber.   
     
     
         4 . The apparatus of  claim 1 ,
 wherein the tip is exposed to the ambient atmosphere; and   wherein the temperature control device alters the temperature of the patterning compound more than the average temperature of the ambient atmosphere.   
     
     
         5 . The apparatus of  claim 1 , wherein the temperature control device alters the temperature of the patterning compound more than the temperature of a substrate onto which the patterning compound may be deposited. 
     
     
         6 . The apparatus of  claim 1 , wherein the temperature control device alters the temperature of a substrate in contact with the patterning compound. 
     
     
         7 . The apparatus of  claim 1 , wherein the patterning compound is octadecylphosphonic acid. 
     
     
         8 . The apparatus of  claim 1 , wherein the patterning compound is 10-undecenyl tricholorosilane. 
     
     
         9 . The apparatus of  claim 1 , wherein the tip is formed on a distal end of a cantilever and the temperature control device is a piezoresistive element integrated into the cantilever. 
     
     
         10 . The apparatus of  claim 1 , wherein the tip is formed on a distal end of a cantilever and the temperature control device is a resistive element integrated into the cantilever. 
     
     
         11 . The apparatus of  claim 1 , wherein the temperature control device is a remote electromagnetic energy source. 
     
     
         12 . The apparatus of  claim 11 , wherein the remote electromagnetic energy source is attuned to an absorption band of the patterning compound. 
     
     
         13 . The apparatus of  claim 11 , wherein the remote electromagnetic energy source is attuned to the absorption band of the tip. 
     
     
         14 . The apparatus of  claim 11 , wherein the remote electromagnetic energy source is attuned to the absorption band of an absorber that is operatively connected to the tip. 
     
     
         15 . The apparatus of  claim 1 , wherein the tip is formed on a distal end of a cantilever and the temperature control device is a cooling element built into the cantilever. 
     
     
         16 . The apparatus of  claim 15 , wherein the cooling element utilizes the Peltier effect. 
     
     
         17 . The apparatus of  claim 15  wherein the cooling element is a thermionic cooler.