Advanced mask cleaning and handling

Abstract

Apparatus for semiconductor device fabrication, includes at least one lithography station, which is adapted to project a pattern of radiation from a mask onto a semiconductor wafer. A mask cleaning station is adapted to receive the mask from the at least one lithography station, to clean the mask so as to remove a contaminant therefrom, and so that the cleaned mask may be returned to the at least one lithography station. A robot is adapted to convey the mask between the at least one lithography station and the mask cleaning station. An enclosure contains the at least one lithography station, the mask cleaning station and the robot, so that the mask is conveyed between the at least one lithography station and the mask cleaning station without human contact and without exposure to ambient air.

1 . A method for semiconductor device fabrication, comprising the steps of: 
 enclosing at least one lithography station and a mask cleaning station in an enclosure, so that a mask may be conveyed between the at least one lithography station and the mask cleaning station without human contact and without exposure to ambient air;    cleaning the mask in the mask cleaning station so as to remove a contaminant therefrom;    conveying the mask within the enclosure from the mask cleaning station to the at least one lithography station;    projecting a pattern of radiation from the mask onto a semiconductor wafer in the at least one lithography station;    wherein cleaning the mask comprises determining position coordinates of the contaminant on the mask, and cleaning the mask locally at a location indicated by the coordinates by applying suction at the location indicated by the coordinates.    
   
   
       2 . A method according to  claim 1 , wherein projecting the pattern of radiation comprises generating the radiation at a wavelength that is less than 160 nm.  
   
   
       3 . A method according to  claim 1 , wherein projecting the pattern of radiation comprises projecting the pattern of radiation from the mask in the absence of a pellicle covering the mask.  
   
   
       4 . A method according to  claim 1 , and comprising storing the mask in a mask storage station, which is at least partially contained in the enclosure.  
   
   
       5 . A method according to  claim 4 , wherein conveying the mask comprises transferring the mask between the at least one lithography station, the mask cleaning station, and the mask storage station.  
   
   
       6 . A method according to  claim 1 , wherein cleaning the mask comprises determining position coordinates of the contaminant on the mask, and cleaning the mask locally at a location indicated by the coordinates.  
   
   
       7 . A method according to  claim 1 , wherein determining the position coordinates comprises enclosing an inspection station within the enclosure, and inspecting the mask using the inspection station.  
   
   
       8 . A method according to  claim 6 , wherein cleaning the mask locally comprises applying suction at the location indicated by the coordinates.  
   
   
       9 . Apparatus according to  claim 1 , wherein cleaning the mask locally further comprises applying a fluid medium to the mask at the location indicated by the coordinates, prior to applying the suction thereto.  
   
   
       10 . Apparatus according to  claim 1 , wherein cleaning the mask locally comprises applying a pressurized cleaning medium to the mask at the location indicated by the coordinates.  
   
   
       11 . A method according to  claim 1 , wherein cleaning the mask comprises controllably directing a beam of electromagnetic energy toward a location of the contaminant on the mask, so as to cause the contaminant to be dislodged from the mask substantially without damage to the mask itself.  
   
   
       12 . A method according to  claim 1 , wherein cleaning the mask further comprises controllably applying an energy transfer medium at the location of the contaminant on the surface, wherein the beam of electromagnetic energy causes local evaporation of the medium, thereby dislodging the contaminant.  
   
   
       13 . A method according to  claim 12 , wherein the electromagnetic energy comprises ultraviolet laser energy.  
   
   
       14 . A method according to  claim 12 , wherein controllably directing the electromagnetic energy comprises receiving input position coordinates of the location of the contaminant on the mask, and directing the beam so that the beam is incident on the mask at the location indicated by the position coordinates.