Inspection Apparatus, Lithographic Apparatus and Method of Measuring a Property of a Substrate

Abstract

A piezo-electric material is placed adjacent to the path of the radiation beam such that, when power is applied to the piezo-electric material it rotates into the path of the radiation beam to block it. A smaller and lighter radiation beam shutter therefore results.

1 . An inspection apparatus, comprising:
 an illumination system configured to condition a radiation beam;   a projector configured to project the radiation beam onto a substrate;   a high numerical aperture lens;   a detector configured to detect the radiation beam after reflection from a surface of the substrate; and   a piezo-electric material configured to move into or out of a path of the radiation beam if a signal to the piezo-electric material is changed.   
     
     
         2 . The inspection apparatus according to  claim 1 , wherein the piezo-electric material is arranged such that at least a portion of the piezo-electric material moves into the path of the radiation beam if the signal to the piezo-electric material is increased. 
     
     
         3 . The inspection apparatus according to  claim 1 , wherein the piezoelectric material is arranged such that at least a portion of the piezo-electric material moves into the path of the radiation beam if the signal to the piezo-electric material is decreased. 
     
     
         4 . The inspection apparatus according to  claim 1 , wherein the piezo-electric material moves into and out of the path of the radiation beam by rotation. 
     
     
         5 . The inspection apparatus according to  claim 1 , further comprising an additional piezo-electric material configured to move into or out of the path of the radiation beam if a signal to the additional piezo-electric material is changed. 
     
     
         6 . The inspection apparatus according to  claim 1 , further comprising an additional illumination system configured to condition an additional radiation beam and an additional piezo-electric material configured to move into or out of the a path of the additional radiation beam if a signal to the additional piezo-electric material is changed. 
     
     
         7 . The inspection apparatus according to  claim 1 , wherein the signal comprises a voltage applied to the piezo-electric material. 
     
     
         8 . A lithographic apparatus comprising:
 an illumination system configured to condition a beam of radiation;   a patterning device support configured to support a patterning device, the patterning device configured to pattern the beam of radiation to form a patterned beam of radiation;   a substrate table configured to hold a substrate;   a projection system configured to project the patterned beam of radiation onto a target portion of the substrate; and   an inspection apparatus configured to measure a property of the substrate, the inspection apparatus comprising:
 an illuminator configured to condition a radiation beam; 
 a projector configured to project the radiation beam onto the substrate; 
 a high numerical aperture lens; 
 a detector configured to detect the radiation beam after reflection from a surface of the substrate; and 
 a piezo-electric material configured to move into or out of a path of the radiation beam if a signal to the piezo-electric material is changed. 
   
     
     
         9 . The lithographic apparatus according to  claim 8 , wherein the piezo-electric material is arranged such that at least a portion of the piezo-electric material moves into the path of the radiation beam if the signal to the piezo-electric material is increased. 
     
     
         10 . The lithographic apparatus according to  claim 9 , wherein the piezoelectric material is arranged such that at least a portion of the piezo-electric material moves into the path of the radiation beam if the signal to the piezo-electric material is decreased. 
     
     
         11 . The lithographic apparatus according to  claim 8 , wherein the piezoelectric material moves into and out of the path of the radiation beam by rotation. 
     
     
         12 . The lithographic apparatus according to  claim 8 , further comprising an additional piezo-electric material configured to move into or out of the path of the radiation beam if a signal to the additional piezo-electric material is changed. 
     
     
         13 . An apparatus, comprising:
 a projector configured to project radiation onto a substrate;   a high numerical aperture lens through which the radiation is projected; and   a piezo-electric material configured to move into or out of ua path of the radiation if a signal to the piezo-electric material is changed.   
     
     
         14 . A method comprising:
 projecting radiation onto a substrate;   detecting the radiation reflected from the substrate, the reflected radiation being indicative of the properties to be measured; and   blocking a path of the radiation by changing a signal applied to a piezo-electric material.   
     
     
         15 . The method according to  claim 14 , wherein the piezo-electric material is arranged such that at least a portion of the piezo-electric material moves into the path of the radiation if the signal to the piezo-electric material is increased. 
     
     
         16 . The method according to  claim 14 , wherein the piezo-electric material is arranged such that at least a portion of the piezo-electric material moves into the path of the radiation if the signal to the piezo-electric material is decreased. 
     
     
         17 . The method according to  claim 14 , wherein the piezo-electric material moves into and out of the path of the radiation by rotation. 
     
     
         18 . The method according to  claim 14 , further comprising blocking the path of the radiation by changing a signal applied to an additional piezo-electric material, the additional piezo-electric material configured to move into or out of the path of the radiation if a signal to the additional piezo-electric material is changed.