System and Method for Using a Two Part Cover and a Box for Protecting a Reticle

Abstract

Systems and methods to protect a mask from being contaminated by airborne particles are described. The systems and methods include providing a reticle secured in a two-part cover. The two part cover includes a removable protection device used to protect the reticle from contaminants. The cover can be held inside a pod or box that can be used to transport the cover through a lithography system from an atmospheric section to a vacuum section. While in the vacuum section, the removable cover can be moved during an exposure process during which a pattern on the reticle can be formed on a wafer.

1 . An apparatus, comprising:
 a frame configured to hold a mask, the frame substantially surrounding the mask around edges of the mask leaving a reflective surface of the mask open, the frame comprising a rim that supports the mask at edges of the reflective surface of the mask.   
     
     
         2 . The apparatus according to  claim 1 , wherein the frame is provided with a tab configured for cooperation with a latch. 
     
     
         3 . The apparatus according to  claim 1 , wherein the frame is provided with registration features that contact the mask, thereby positioning the mask with respect to the frame. 
     
     
         4 . The apparatus according to  claim 1 , wherein the registration features are provided to at least one corner of the frame. 
     
     
         5 . The apparatus according to  claim 1 , wherein the frame is provided with a hole configured to cooperate with a kinematic locator. 
     
     
         6 . The apparatus of  claim 1 , further comprising:
 a plate substantially a same size as the reflective surface of the mask, the plate having a first side facing towards the mask and a second side facing away from the mask.   
     
     
         7 . The apparatus according to  claim 6 , wherein the plate is provided with a kinematic locator that protrudes from the first side of the plate and that contacts the frame. 
     
     
         8 . The apparatus according to  claim 6 , wherein the plate is transparent to allow for inspection of the reflective surface of the mask. 
     
     
         9 . A cover for covering a reticle with a reflective surface, comprising:
 a plate having substantially a same size as the reflective surface, and, in use being held substantially parallel to the reflective surface, the plate allowing for inspection of the reflective surface of the reticle; and   a frame portion associated with the plate, the frame portion comprising registration features configured to contact the reticle at its edges, thereby positioning the reticle with respect to the plate.   
     
     
         10 . The cover according to  claim 9 , wherein the frame is provided with a part of a kinematic locator.