Electron source and electron beam apparatus
AssigneeCanon Kabushiki Kaisha
InventorsHideaki Mitsutake, Naoto Nakamura, Yoshihisa Sano
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Abstract
An electron source or electron beam apparatus comprises an electron-emitting device and a shield member disposed above the electron-emitting device. The electron-emitting device generates an electric field component, when energized, that is parallel to a substrate surface on which the electron-emitting device is disposed, while the shield member has an aperture which allows electrons emitted from the electron-emitting device to pass therethrough, but blocks off charged particles flying toward the electron emitting device.
Claims38
An electron source comprising a substrate having a surface, an electron-emitting device having an electron-emitting region between a higher potential electrode and a lower potential electrode disposed side by side on said surface, and a shield member for blocking off positive ions flying toward said electron-emitting device, said shield member having an opening for allowing electrons emitted from said electron-emitting device to pass therethrough, wherein said shield member covers the area right above said electron-emitting device, and said opening deviates from the direction normal to the electron-emitting region toward the higher potential electrode side by a distance .delta. (in .mu.m) represented by the formula:
- ##EQU2## where d:
- height from device to opening (.mu.m);
- V.sub.f :
- device-driving voltage applied to device (V);
- V.sub.v :
- potential difference between opening and electron-emitting region (V).
An electron beam apparatus comprising a substrate having a surface, an electron-emitting device having an electron-emitting region between a higher potential electrode and a lower potential electrode disposed side by side on said surface, a shield member for blocking off positive ions flying toward said electron-emitting device, said shield member having an opening for allowing electrons emitted from said electron-emitting device to pass therethrough, and an irradiated member to which an electron beam emitted from said electron-emitting device is irradiated, wherein said shield member covers the area right above said electron-emitting device and said opening deviates from the direction normal to the electron-emitting region toward the higher potential electrode side by a distance .delta. (in .mu.m) represented by the formula:
- ##EQU3## where d:
- height from device to opening (.mu.m);
- V.sub.f :
- device-driving voltage applied to device (V);
- V.sub.v :
- potential difference between opening and electron-emitting region (V).
Dependencies are inferred from the claim text.