Method and apparatus for cleaning/drying hydrophobic wafers

Abstract

A method and an apparatus that uses a surfactant to clean a hydrophobic wafer is provided. In a first aspect, the method may clean and dry a wafer without applying pure DI water to the wafer. In a second aspect, the method may clean a wafer by applying pure DI water to the wafer only for a short duration of time such that the DI water application ceases prior to or as soon as a surfactant solution is rinsed from the wafer thereafter the wafer is dried. In a further aspect a hydrophobic wafer is maintained wetted with surfactant as it is transferred between cleaning apparatuses and is rinsed via diluted surfactant or via a brief DI water spray and is thereafter dried.

The invention claimed is:  
     
         1 . A method of cleaning a hydrophobic wafer, comprising: 
 applying a surfactant containing solution to a surface of a hydrophobic wafer in a first cleaning apparatus to thereby form a layer of surfactant on the surface of the hydrophobic wafer;    transferring the hydrophobic wafer having the surfactant layer formed thereon to a second cleaning apparatus;    rinsing the surface of a hydrophobic wafer with pure DI water in the second cleaning apparatus; and    drying the hydrophobic wafer in the second cleaning apparatus;    wherein pure DI water is applied to the hydrophobic wafer only in the rinsing step and wherein transferring the hydrophobic wafer to a second cleaning apparatus comprises maintaining a layer of surfactant containing solution on the hydrophobic wafer as the hydrophobic wafer transfers to a second cleaning apparatus.    
     
     
         2 . The method of  claim 1  wherein applying a surfactant containing solution to a surface of a hydrophobic wafer in a first cleaning apparatus comprises at least partially submerging the hydrophobic wafer in a tank of fluid that contains a surfactant containing solution.  
     
     
         3 . The method of  claim 1  wherein applying a surfactant containing solution to a surface of a hydrophobic wafer in a first cleaning apparatus comprising scrubbing the hydrophobic wafer using the surfactant containing solution in a first scrubber.  
     
     
         4 . The method of  claim 1  wherein transferring the hydrophobic wafer to a second cleaning apparatus comprises transferring the hydrophobic wafer to a scrubber.  
     
     
         5 . The method of  claim 1  wherein transferring the hydrophobic wafer to a second cleaning apparatus comprises transferring the hydrophobic wafer to a spin-rinse-dryer.  
     
     
         6 . The method of  claim 1  wherein the surfactant containing solution comprises a WAKO NCW surfactant.  
     
     
         7 . The method of  claim 6  wherein the WAKO NCW surfactant comprises a concentration of 0.01% to 0.1% by volume.  
     
     
         8 . The method of  claim 1  wherein rinsing the surface of a hydrophobic wafer with pure DI water in a second cleaning apparatus comprises rinsing the surface of a hydrophobic wafer with pure DI water in a second cleaning apparatus for 5 seconds or less.  
     
     
         9 . The method of  claim 1  wherein transferring the hydrophobic wafer to a second cleaning apparatus comprises transferring the hydrophobic wafer to an IPA dryer.  
     
     
         10 . The method of  claim 1  wherein drying the hydrophobic wafer comprises Marangoni drying the hydrophobic wafer.  
     
     
         11 . A method of rinsing and drying a hydrophobic wafer, comprising: 
 placing a hydrophobic wafer in a cleaning apparatus;    applying a diluted surfactant to the surface of the hydrophobic wafer within the cleaning apparatus; and    drying the hydrophobic wafer within the cleaning apparatus.    
     
     
         12 . The method of  claim 11  wherein the diluted surfactant containing solution comprises a concentration of 0.01% to 0.1% surfactant by volume.  
     
     
         13 . The method of  claim 11  wherein the diluted surfactant is applied for five seconds or less.  
     
     
         14 . The method of  claim 11  wherein placing a hydrophobic wafer in a cleaning apparatus comprises placing the hydrophobic wafer in a spin-rinse-dryer.  
     
     
         15 . The method of  claim 11  wherein placing a hydrophobic wafer in a cleaning apparatus comprises placing the hydrophobic wafer in a scrubber.  
     
     
         16 . The method of  claim 11  wherein placing a hydrophobic wafer in a cleaning apparatus comprises placing the hydrophobic wafer in a Marangoni dryer and wherein drying the hydrophobic wafer comprises Marangoni drying.  
     
     
         17 . The method of  claim 16  wherein the Marangoni dryer comprises a tank containing a surfactant.  
     
     
         18 . The method of  claim 16  wherein the Marangoni dryer comprises a spin-rinse-dryer.  
     
     
         19 . A method of rinsing and drying a hydrophobic wafer, comprising: 
 placing a hydrophobic wafer in a cleaning apparatus;    applying a surfactant to the surface of the hydrophobic wafer to form a surfactant layer thereon;    spraying pure deionized water on the surface of the hydrophobic wafer;    ceasing the deionized water spray as soon as the surfactant layer is rinsed from the surface of the hydrophobic wafer; and    drying the hydrophobic wafer.    
     
     
         20 . The method of  claim 19  wherein placing a hydrophobic wafer in a cleaning apparatus comprises placing the hydrophobic wafer in a spin-rinse-dryer.  
     
     
         21 . The method of  claim 19  wherein placing a hydrophobic wafer in a cleaning apparatus comprises placing the hydrophobic wafer in a scrubber.  
     
     
         22 . The method of  claim 19  wherein placing a hydrophobic wafer in a cleaning apparatus comprises placing the hydrophobic wafer in a Marangoni dryer and wherein drying the hydrophobic wafer comprises Marangoni drying.  
     
     
         23 . A method of rinsing and drying a hydrophobic wafer, comprising: 
 placing a hydrophobic wafer in a cleaning apparatus;    applying a surfactant to the surface of the hydrophobic wafer to form a surfactant layer thereon;    spraying pure deionized water on the surface of the hydrophobic wafer;    ceasing the deionized water spray within five seconds; and    drying the hydrophobic wafer.    
     
     
         24 . The method of  claim 23  wherein placing a hydrophobic wafer in a cleaning apparatus comprises placing the hydrophobic wafer in a spin-rinse-dryer.  
     
     
         25 . The method of  claim 23  wherein placing a hydrophobic wafer in a cleaning apparatus comprises placing the hydrophobic wafer in a scrubber.  
     
     
         26 . The method of  claim 23  wherein placing a hydrophobic wafer in a cleaning apparatus comprises placing the hydrophobic wafer in a Marangoni dryer and wherein drying the hydrophobic wafer comprises Marangoni drying.  
     
     
         27 . A method of rinsing and drying a hydrophobic wafer, comprising: 
 placing a hydrophobic wafer in a cleaning apparatus;    applying a surfactant to the surface of the hydrophobic wafer to form a surfactant layer thereon;    spraying pure deionized water on the surface of the hydrophobic wafer;    ceasing the deionized water spray before the surfactant layer is completely rinsed from the surface of the hydrophobic wafer; and    drying the hydrophobic wafer.    
     
     
         28 . The method of  claim 27  wherein placing a hydrophobic wafer in a cleaning apparatus comprises placing the hydrophobic wafer in a spin-rinse-dryer.  
     
     
         29 . The method of  claim 27  wherein placing a hydrophobic wafer in a cleaning apparatus comprises placing the hydrophobic wafer in a scrubber.  
     
     
         30 . The method of  claim 27  wherein placing a hydrophobic wafer in a cleaning apparatus comprises placing the hydrophobic wafer in a Marangoni dryer and wherein drying the hydrophobic wafer comprises Marangoni drying.