Semiconducting cold photocathode device using electric field to control the electron affinity
OwnerNicolas Tappy, Christian Monachon +2inventors
InventorsNicolas Tappy, Christian Monachon, Anna Fontcuberta i Morral, Jean Berney
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Abstract
An electron emitter comprises a tapered-shaped emission tip having a base face and an apex opposite the base face, the emission tip consisting essentially of semiconductor material, the semiconductor material being partially doped n-type and partially doped p-type, wherein the base face is doped one of n-type or p-type and the apex is doped opposite type of the base face and a p-n junction is thereby formed at a position between the base face and the apex.
Claims24
An electron emitter, comprising:
- a tapered-shaped emission tip having a base face and an apex opposite the base face, the emission tip consisting essentially of semiconductor material, the semiconductor material being doped p-type at least at the apex, wherein the doped p-type level in conjunction with the geometry of the tapered-shaped emission tip shift the work function of the semiconductor material sufficiently close to vacuum level to enable emission of electrons upon absorption of photons.
An electron source, comprising:
- an electron emitter;
- a suppressor lens;
- and
- an extractor lens;
- wherein the electron emitter comprises a tapered-shaped emission tip having a base face and an apex opposite the base face, the emission tip consisting essentially of semiconductor material, the semiconductor material at the apex being doped p-type, and wherein the base face is doped one of n-type or p-type.
A multiple-electron beams apparatus, comprising:
- a substrate made of semiconducting material doped with a n-type or p-type dopant, the substrate having a sidewall, a first surface and a second surface;
- a plurality of emission tips formed on the first surface of the substrate, each emission tip having a tapered-shape with a base attached to the first surface and an apex, each emission tip being doped p-type at the apex;
- an ohmic contact formed of the sidewall or on the second surface of the substrate.
Dependencies are inferred from the claim text.