Method and apparatus for aberration-insensitive electron beam imaging
AssigneeKLA-Tencor Technologies Corporation
InventorsSrinivas Vedula, Amir Azordegan, Laurence Hordon, Alan D. Brodie, Gian Francesco Lorusso, Takuji Tada
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Abstract
One embodiment relates to an electron beam apparatus for automated imaging of a substrate surface. An electron source is configured to emit electrons, and a gun lens is configured to focus the electrons emitted by the electron source so as to form an electron beam. A condenser lens system is configured to receive the electron beam and to reduce its numerical aperture to an ultra-low numerical aperture. An objective lens is configured to focus the ultra-low numerical aperture beam onto the substrate surface. Other embodiments are also disclosed.
Claims20
An electron beam apparatus for automated imaging of a substrate surface, the apparatus comprising:
- an electron source configured to emit electrons;
- a gun lens configured to focus the electrons emitted by the electron source so as to form an electron beam;
- a condenser and objective lens system configured to receive the electron beam and to reduce a numerical aperture of the beam to an ultra-low numerical aperture, wherein aberration-insensitive imaging is performed without aberration correction.
A method of aberration-insensitive electron beam imaging of a substrate surface, the method comprising:
- emitting electrons from an electron source;
- focusing the electrons emitted by the electron source by a gun lens so as to form an electron beam;
- reducing a numerical aperture of the beam to an ultra-low numerical aperture by a condenser and objective lens system, wherein aberration-insensitive imaging is performed without aberration correction step.
An apparatus configured for aberration-insensitive electron beam imaging of a substrate surface, the apparatus comprising:
- means for emitting electrons;
- means for focusing the electrons emitted by the electron source so as to form an electron beam;
- electron lenses configured to reduce a numerical aperture of the beam to an ultra low numerical aperture, wherein aberration-insensitive imaging is performed without aberration correction.
Dependencies are inferred from the claim text.