Wet Surface Treatment By Usage of a Liquid Bath Containing Energy Limited Bubbles

Abstract

A method controllably and sustainably creates an upwardly directed gradient of dropping temperatures in a wet treatment tank between a cooled and face down workpiece (e.g., an in-process semiconductor wafer) and a lower down heat source. A thermal fluid upwell containing thermally collapsible bubbles is then directed from the heat source to the face down workpiece. In one class of embodiments, bubble collapse energy release and/or bubble collapse locations are controlled so as to avoid exposing delicate features of the to-be-treated surface to damaging forces. In one class of embodiments the wet treatment includes ultra-cleaning of the work face. Cleaning fluids that are essentially free of predefined contaminates are upwelled to the to-be-cleaned surface and potentially contaminated after-flows are convectively directed away from the workpiece so as to prevent recontamination of the workpiece.

1 - 12 . (canceled) 
     
     
         13 . A wet treatment method comprising:
 generating and maintaining in a liquid bath, a temperature gradient having a relatively high first temperature at a lower portion of the gradient and a substantially cooler second temperature at a higher portion of the gradient where the relatively high first temperature is at or above a boiling point of a pre-identified vapor and the substantially cooler second temperature is below said boiling point of the pre-identified vapor;   generating a plurality of in-liquid thermally collapsible bubbles containing said pre-identified vapor;   causing the generated thermally collapsible bubbles to rise through said temperature gradient; and   automatically adjusting at least one of said first and second temperatures so as thereby define a location in said temperature gradient where the boiling point of the pre-identified vapor is crossed.   
     
     
         14 . The wet treatment method of  claim 13  wherein:
 said pre-identified vapor is water vapor. 
 
     
     
         15 . The wet treatment method of  claim 13  wherein:
 said pre-identified vapor is a vapor of an organic compound. 
 
     
     
         16 . The wet treatment method of  claim 13  wherein:
 said in-liquid thermally collapsible bubbles contain a mixture of vapors including the pre-identified vapor. 
 
     
     
         17 . The wet treatment method of  claim 13  wherein:
 said generating and maintaining of the cooler second temperature includes moving a cooling fluid through a heat exchanger. 
 
     
     
         18 . The wet treatment method of  claim 13  wherein:
 said generating and maintaining of the relatively high first temperature includes passing electrical current through an electrical impedance. 
 
     
     
         19 . A wet treatment apparatus comprising:
 a tank for supporting therein one or more liquid layers;   a temperature gradient producer operatively coupled to at least one of the liquid layers of said tank for generating and maintaining a temperature gradient within at least the one liquid layer where the temperature gradient has a relatively high first temperature at a lower portion of the gradient and a substantially cooler second temperature at a higher portion of the gradient, where the relatively high first temperature is at or above a boiling point of a pre-identified vapor and the substantially cooler second temperature is below said boiling point of the pre-identified vapor; and   a bubbles generator operatively coupled to at least one of the liquid layers of said tank for generating in-liquid bubbles in the at least one liquid layer.   
     
     
         20 . The wet treatment apparatus of  claim 19  wherein:
 said pre-identified vapor is water vapor. 
 
     
     
         21 . The wet treatment apparatus of  claim 19  and further comprising:
 an active cooling element operatively coupled to at least one of the liquid layers of said tank for creating a downdraft of cool liquid in the at least one liquid layer where the downdraft is oriented for moving potentially contaminated liquid away from a pre-identified cleaning area. 
 
     
     
         22 . One or more of inventions disclosed here within (and within any parent of this application) as such one or more disclosed inventions are taken alone or in combinations one with at least another, where such one or more disclosed inventions are incorporated here-at and thus contained and defined (bounded) by this claim. 
     
     
         23 . The subject matter of  claim 22  and further narrowed to being A method comprising subjecting a patterned face of a supplied workpiece to a liquid in which thermally collapsible bubbles are thermally collapsing proximate to pattern features of the patterned face so as to induce agitation of the liquid at the positions of the pattern features but without damaging the pattern features. 
     
     
         24 . The subject matter of  claim 22  and further narrowed to being An apparatus configured to subject a patterned face of a supplied workpiece to a liquid in which thermally collapsible bubbles are thermally collapsing proximate to pattern features of the patterned face so as to induce agitation of the liquid at the positions of the pattern features but without damaging the pattern features.