Compositions and methods for drying patterned wafers during manufacture of integrated circuitry products

Abstract

Drying of patterned wafers is achieved in a manner effecting removal of water from the patterned wafers without collapse or deterioration of the pattern structures thereof. The drying is carried out in one aspect of the invention with a composition containing supercritical fluid, and at least one water-reactive agent that chemically reacts with water to form reaction product(s) more soluble in the supercritical fluid than water. Various methodologies are described for use of supercritical fluids to dry patterned wafers, which avoid the (low water solubility) deficiency of supercritical fluids such as supercritical CO 2 .

1 - 25 . (canceled)  
   
   
       26 . A method of drying a patterned wafer to remove water therefrom, said method comprising contacting said patterned wafer with a first composition comprising liquid CO 2 , and thereafter contacting the patterned substrate with a second composition comprising SCCO2, thereby effecting drying of the patterned substrate without damage to the pattern thereof.  
   
   
       27 . The method of  claim 26 , wherein the first composition contacting step is carried out at temperature in a range of from about 20 to about 30° C.  
   
   
       28 . The method of  claim 27 , wherein the first composition contacting step is carried out for a time in a range of from about 0.5 to about 20 minutes.  
   
   
       29 . The method of  claim 26 , wherein the second composition contacting step is carried out at temperature in a range of from about 32 to about 75° C.  
   
   
       30 . The method of  claim 29 , wherein the second composition contacting step is carried out for a time in a range of from about 0.5 to about 20 minutes.  
   
   
       31 . The method of  claim 26 , wherein the first composition contacting step is carried out at temperature in a range of from about 20 to about 30° C. for a time in a range of from about 0.5 to about 20 minutes, and the second composition contacting step is carried out at temperature in a range of from about 32 to about 75° C. for a time in a range of from about 0.5 to about 20 minutes.  
   
   
       32 . A method of drying a patterned wafer to remove water therefrom, said method comprising (a) contacting said patterned wafer with a first composition comprising alcohol at pressure above about 1000 psi and temperature below 32° C., (b) contacting said patterned wafer with a second composition comprising an alcohol/CO 2  solution, and (c) contacting the patterned substrate with a third composition comprising SCCO2, thereby effecting drying of the patterned substrate without damage to the pattern thereof.  
   
   
       33 . The method of  claim 32 , wherein said contacting (a) is carried out for a period of from about 1 minute to about 15 minutes.  
   
   
       34 . The method of  claim 32 , wherein said alcohol of said first composition comprises at least one C 1 -C 4  alcohol.  
   
   
       35 . The method of  claim 32 , wherein said alcohol of said first composition comprises methanol.  
   
   
       36 . The method of  claim 32 , wherein said alcohol of said first composition is the same as alcohol of the second composition.  
   
   
       37 . The method of  claim 32 , wherein said first composition is recirculated in contact with the patterned wafer.  
   
   
       38 . The method of  claim 32 , wherein the second composition is recirculated in contact with the patterned wafer.  
   
   
       39 . The method of  claim 32 , wherein the third composition is recirculated in contact with the patterned wafer.  
   
   
       40 . The method of  claim 32 , wherein said contacting (b) is carried out at temperature in a range of from about 22 to about 31° C.  
   
   
       41 . The method of  claim 32 , wherein said contacting (b) is carried out for a period of from about 0.5 to about 20 minutes.  
   
   
       42 . The method of  claim 32 , wherein said contacting (c) is carried out at temperature in a range of from about 32 to about 75° C.  
   
   
       43 . The method of  claim 32 , wherein said contacting (c) is carried out for a time of from about 0.5 to about 20 minutes.  
   
   
       44 . The method of  claim 32 , wherein concentration of said alcohol in said second composition is in a range of from about 1 to about 15% by weight, based on total weight of said alcohol and said CO 2  therein.  
   
   
       45 . The method of  claim 32 , wherein the contacting steps (a), (b) and (c) are carried out in a same chamber.