A scanning electron beam apparatus which two-dimensionally scans a sample by an electron beam to achieve high resolution even with a photoexcited electron source. The electron beam apparatus includes a photocathode including a substrate having a refractive index of more than 1.7 and a photoemissive film, a focusing lens configured to focus an excitation light toward the photocathode, an extractor electrode disposed facing the photocathode and configured to accelerate an electron beam generated from the photoemissive film by focusing the excitation light by the focusing lens and emitting the excitation light through the substrate, and an electron optics including a deflector configured to two-dimensionally scan a sample by the electron beam accelerated by the extractor electrode. For a spherical aberration of the focusing lens, a root mean square of the spherical aberration on the photoemissive film is equal to or less than 1/14 of a wavelength of the excitation light.

A photoelectric surface includes a window material, a photoelectric conversion layer provided with a light incidence surface and an electron emission surface, and a carbon layer provided on the electron emission surface.

An image sensor has a photocathode window assembly, an anode assembly, and a malleable metal seal. The photocathode window assembly has a photocathode layer. The anode assembly includes a silicon substrate that has an electron sensitive surface. The malleable metal seal bonds the photocathode window assembly and the silicon substrate to each other. A vacuum gap separates the photocathode layer from the electron sensitive surface. A first electrical connection and a second electrical connection are for a voltage bias of the photocathode layer relative to the electron sensitive surface.

An image sensor has a photocathode window assembly, an anode assembly, and a malleable metal seal. The photocathode window assembly has a photocathode layer. The anode assembly includes a silicon substrate that has an electron sensitive surface. The malleable metal seal bonds the photocathode window assembly and the silicon substrate to each other. A vacuum gap separates the photocathode layer from the electron sensitive surface. A first electrical connection and a second electrical connection are for a voltage bias of the photocathode layer relative to the electron sensitive surface.

According to one embodiment, an electron-emitting element includes a first member and a second member. The first member includes a semiconductor member of an n-type. The second member includes a diamond member a p-type and includes at least one selected from the group consisting of diamond and graphite. The semiconductor member includes at least one selected from the group consisting of a first material, a second material, and a third material. The first material includes nitrogen and at least one selected from the group consisting of B, Al, In, and Ga. The second material includes at least one selected from the group consisting of ZnO and ZnMgO. The third material includes at least one selected from the group consisting of BaTiO.sub.3, PbTiO.sub.3, Pb(Zr.sub.x, Ti.sub.1-x)O.sub.3, KNbO.sub.3, LiNbO.sub.3, LiTaO.sub.3, Na.sub.xWO.sub.3, Zn.sub.2O.sub.3, Ba.sub.2NaNb.sub.5O.sub.5, Pb.sub.2KNb.sub.5O.sub.15, and Li.sub.2B.sub.4O.sub.7.

According to one embodiment, an electron-emitting element includes a first member and a second member. The first member includes a semiconductor member of an n-type. The second member includes a diamond member a p-type and includes at least one selected from the group consisting of diamond and graphite. The semiconductor member includes at least one selected from the group consisting of a first material, a second material, and a third material. The first material includes nitrogen and at least one selected from the group consisting of B, Al, In, and Ga. The second material includes at least one selected from the group consisting of ZnO and ZnMgO. The third material includes at least one selected from the group consisting of BaTiO.sub.3, PbTiO.sub.3, Pb(Zr.sub.x, Ti.sub.1-x)O.sub.3, KNbO.sub.3, LiNbO.sub.3, LiTaO.sub.3, Na.sub.xWO.sub.3, Zn.sub.2O.sub.3, Ba.sub.2NaNb.sub.5O.sub.5, Pb.sub.2KNb.sub.5O.sub.15, and Li.sub.2B.sub.4O.sub.7.

Methods of producing microrods for electron emitters and associated microrods and electron emitters. In one example, a method of producing a microrod for an electron emitter comprises providing a bulk crystal ingot, removing a first plate from the bulk crystal ingot, reducing a thickness of the first plate to produce a second plate, and milling the second plate to produce one or more microrods. In another example, a microrod for an electron emitter comprises a microrod tip region that comprises a nanoneedle that in turn comprises a nanorod and a nanoprotrusion tip. The microrod and the nanoneedle are integrally formed from a bulk crystal ingot by sequentially: (i) removing the microrod from the bulk crystal ingot; (ii) coarse processing the microrod tip region to produce the nanorod; and (iii) fine processing the nanorod to produce the nanoprotrusion tip.

Methods of producing microrods for electron emitters and associated microrods and electron emitters. In one example, a method of producing a microrod for an electron emitter comprises providing a bulk crystal ingot, removing a first plate from the bulk crystal ingot, reducing a thickness of the first plate to produce a second plate, and milling the second plate to produce one or more microrods. In another example, a microrod for an electron emitter comprises a microrod tip region that comprises a nanoneedle that in turn comprises a nanorod and a nanoprotrusion tip. The microrod and the nanoneedle are integrally formed from a bulk crystal ingot by sequentially: (i) removing the microrod from the bulk crystal ingot; (ii) coarse processing the microrod tip region to produce the nanorod; and (iii) fine processing the nanorod to produce the nanoprotrusion tip.

A photoelectric-surface electron source includes: a glass substrate that receives laser light from a substrate light-receiving surface including microlenses and that focuses the laser light toward a substrate main surface located on the opposite side from the substrate light-receiving surface; a photoelectric surface that is provided to the substrate main surface, and that receives the focused laser light and emits photoelectrons; and an extraction electrode that is fixed to the substrate main surface and that extracts the photoelectrons from the photoelectric surface. The extraction electrode is disposed away from the photoelectric surface along the normal direction of the substrate main surface and has: an electrode part in which electrode holes for allowing the photoelectrons to pass therethrough are provided; and a frame part that is fixed to a region surrounding the photoelectric surface in the substrate main surface.

A photoelectric-surface electron source includes: a glass substrate that receives laser light from a substrate light-receiving surface including microlenses and that focuses the laser light toward a substrate main surface located on the opposite side from the substrate light-receiving surface; a photoelectric surface that is provided to the substrate main surface, and that receives the focused laser light and emits photoelectrons; and an extraction electrode that is fixed to the substrate main surface and that extracts the photoelectrons from the photoelectric surface. The extraction electrode is disposed away from the photoelectric surface along the normal direction of the substrate main surface and has: an electrode part in which electrode holes for allowing the photoelectrons to pass therethrough are provided; and a frame part that is fixed to a region surrounding the photoelectric surface in the substrate main surface.