Charged Particle Beam Apparatus

Abstract

An object of the present disclosure is to provide a charged particle beam apparatus that can quickly find a correction condition for a new aberration that is generated in association with beam adjustment. In order to achieve the above object, the present disclosure proposes a charged particle beam apparatus configured to include an objective lens (7) configured to focus a beam emitted from a charged particle source and irradiate a specimen, a visual field movement deflector (5 and 6) configured to deflect an arrival position of the beam with respect to the specimen, and an aberration correction unit (3 and 4) disposed between the visual field movement deflector and the charged particle source, in which the aberration correction unit is configured to suppress a change in the arrival position of the beam irradiated under different beam irradiation conditions.

1 . A charged particle beam apparatus comprising:
 an objective lens configured to focus a beam emitted from a charged particle source and irradiate a specimen;   visual field movement deflectors configured to deflect an arrival position of the beam with respect to the specimen; and   an aberration correction unit disposed between the visual field movement deflectors and the charged particle source, wherein   the aberration correction unit is configured to suppress a change in the arrival position of the beam irradiated under different beam irradiation conditions.   
     
     
         2 . The charged particle beam apparatus according to  claim 1 , wherein
 the aberration correction unit includes one or more lenses and one or more deflectors that deflect the beam passing through the one or more lenses.   
     
     
         3 . The charged particle beam apparatus according to  claim 2 , wherein
 the one or more lenses are rotationally symmetric lenses or multipole lenses.   
     
     
         4 . The charged particle beam apparatus according to  claim 1 , further comprising:
 a control device that controls an acceleration electrode for accelerating the beam emitted from the charged particle source toward the specimen and a voltage applied to the acceleration electrode, wherein   the control device controls the aberration correction unit so as to suppress the change in the arrival position of the beam when a voltage applied to the acceleration electrode is changed.   
     
     
         5 . The charged particle beam apparatus according to  claim 1 , wherein
 the control device controls the visual field movement deflector so as to return to a trajectory when aberration correction using the aberration correction unit is not performed.   
     
     
         6 . The charged particle beam apparatus according to  claim 5 , wherein
 the visual field movement deflector includes at least an upper visual field movement deflector and a lower visual field movement deflector, and   the control device controls deflection conditions of the upper visual field movement deflector and the lower visual field movement deflector according to aberration correction conditions of the aberration correction unit.   
     
     
         7 . The charged particle beam apparatus according to  claim 6 , wherein
 the control device adjusts the deflection conditions of the upper visual field movement deflector and the lower visual field movement deflector to have a predetermined ratio.   
     
     
         8 . The charged particle beam apparatus according to  claim 1 , wherein
 one or more condenser lenses and one or more axis adjustment deflectors that deflect a beam passing through the condenser lenses are provided between the aberration correction unit and the objective lens.   
     
     
         9 . A method of positioning a visual field at a desired position on a specimen by using a visual field movement deflector that changes an arrival position of a beam emitted from a charged particle source, the method comprising:
 deflecting the beam to a desired arrival position by using the visual field movement deflector;   adjusting a deflection condition of the visual field movement deflector so as to cancel an inclination of an incident beam when the beam is deflected to the desired arrival position; and   adjusting an aberration correction unit disposed between the charged particle source and the visual field movement deflector so as to cancel off-axis chromatic aberration generated according to an amount of visual field movement by the visual field movement deflector, off-axis chromatic aberration generated according to the amount of visual field movement, and off-axis chromatic aberration generated by setting the deflection condition of the visual field movement deflector so as to cancel the inclination of the incident beam.   
     
     
         10 . A charged particle beam apparatus comprising:
 an objective lens configured to focus a beam emitted from a charged particle source and irradiate a specimen;   a visual field movement deflector configured to deflect an arrival position of the beam with respect to the specimen;   an aberration correction unit disposed between the visual field movement deflector and the charged particle source; and   a control device that controls the visual field movement deflector and the aberration correction unit, wherein   the control device
 deflects the beam to a desired arrival position by using the visual field movement deflector, 
 adjusts a deflection condition of the visual field movement deflector so as to cancel an inclination of an incident beam when the beam is deflected to the desired arrival position, and 
 adjusts the aberration correction unit so as to cancel off-axis chromatic aberration generated according to an amount of visual field movement by the visual field movement deflector, off-axis chromatic aberration generated according to the amount of visual field movement, and off-axis chromatic aberration generated by setting the deflection condition of the visual field movement deflector so as to cancel the inclination of the incident beam. 
   
     
     
         11 . A charged particle beam apparatus comprising:
 an objective lens configured to focus a beam emitted from a charged particle source and irradiate a specimen; and   a first lens disposed between the objective lens and the charged particle source;   a second lens;   a first deflector and a second deflector that deflect abeam passing through each lens; and   a control device that controls the first lens, the second lens, the first deflector, and the second deflector, wherein   the control device generates off-axis chromatic aberration and off-axis coma aberration having the same amount as off-axis chromatic aberration and off-axis coma aberration generated by the objective lens, in a direction opposite to the off-axis chromatic aberration and off-axis coma aberration generated by the objective lens, by controlling the first lens, the second lens, the first deflector, and the second deflector.