Electron beam apparatus, a device manufacturing method using the same apparatus, a pattern evaluation method, a device manufacturing method using the same method, and a resist pattern or processed wafer evaluation method

Abstract

An object of the present invention is to provide an electron beam apparatus, in which a plurality of electron beams, e.g., four electron beams, is produced for one optical axis with a relatively high current achieved for each electron beam. Provided is an electron beam apparatus comprising: an electron beam emitter ( 32 ) having an electron gun ( 30 ), said electron gun ( 30 ) disposed along an optical axis ( 23 ) and operable to emit a plurality of off-axis electron beams along a direction defined by a certain angle with respect to the optical axis ( 23 ); a plurality of apertures ( 34 ) disposed at a location offset from the optical axis ( 23 ); and an electromagnetic lens ( 7 ) for forming a magnetic field between the electron gun ( 30 ) and the apertures ( 34 ) to control the plurality of off-axis electron beams emitted from the electron gun ( 30 ) so that the plurality of off-axis electron beams passes through the apertures ( 34 ).

1 . An electron beam apparatus comprising:
 an electron beam source for emitting a primary electron beam;   a primary optical system for guiding said primary electron beam onto a sample surface so as to scan said sample with said primary electron beam;   a secondary electron detecting unit having a detection surface for detecting a secondary electron beam emitting from said sample; and   a secondary optical system for guiding an image of said secondary electron beam emitting from said sample onto the detection surface of said secondary electron detecting unit to thus form a focused image, wherein   said primary optical system comprises a lens operable to irradiate said primary electron beam emitted from said electron beam source in a size larger than a pixel size on said sample surface, and   said secondary optical system comprises a magnifying lens to magnify the image of said secondary electron beam emitted from said sample into the focused image on said detection surface, wherein   said detection surface selectively detects the secondary electron beam emitted from a specific area on the sample corresponding to said pixel size on the sample surface among the secondary electron beam which has emitted from said sample and passed through said magnifying lens.   
   
   
       2 . An electron beam apparatus in accordance with  claim 1 , in which
 said detection surface is sized to be substantially equal to or smaller than a product of the pixel size on said sample surface and a magnification ratio of said magnifying lens.   
   
   
       3 . An electron beam apparatus in accordance with  claim 1  or  2 , in which
 said electron beam apparatus comprises a controller for controlling said electron beam apparatus, and   said secondary optical system further comprises a deflector, wherein   said controller controls said deflector to be synchronized with the scanning operation of said primary electron beam over the sample surface to make a correction so that said secondary electron beam emanating from the sample as a result of the scanning operation by said primary electron beam can be focused on said aperture or said detection surface at any time.   
   
   
       4 . An electron beam apparatus in accordance with  claim 1 , in which
 said apparatus comprises a plurality of said magnifying lenses, wherein a lens in a first stage thereof is defined by a lens set comprising an electromagnetic lens in combination with an axisymmetric electrode disposed within said electromagnetic lens and applied with a positive voltage.   
   
   
       5 . An electron beam apparatus in accordance with  claim 1 , in which
 said primary optical system further comprises a multi-aperture for forming a plurality of primary electron beams from the primary electron beam emitted from said primary electron beam source, so that said plurality of primary electron beams formed through said multi-aperture is available in the scanning on said sample surface.