A photocathode epitaxial structure. The photocathode epitaxial structure includes a binary compound substrate material. The photocathode epitaxial structure further includes an active device absorber layer forming a portion of a p-type device photocathode formed on the binary compound substrate material. The active device absorber layer comprising at least a quaternary or greater material structure configured to be lattice matched with the substrate material to reduce strain to allow charge carriers to go further in the active device absorber layer implemented in the photocathode of a nightvision system.

A photocathode for use in vacuum electronic devices has a bandgap gradient across the thickness (or depth) of the photocathode between the emitting surface and the opposing surface. This bandgap gradient compensates for depth-dependent variations in transport energetics. When the bandgap energy E.sub.BG(z) is increased for electrons with shorter path lengths to the emitting surface and decreased for electrons with longer path lengths to the emitting surface, such that the sum of E.sub.BG(z) and the scattering energy is substantially constant or similar for electrons photoexcited at all locations within the photocathode, the energies of the emitted electrons may be more similar (have less variability), and the emittance of the electron beam may be desirably decreased. The photocathode may be formed of a III-V semiconductor such as InGaN or an oxide semiconductor such as GaInO.

A photocathode for use in vacuum electronic devices has a bandgap gradient across the thickness (or depth) of the photocathode between the emitting surface and the opposing surface. This bandgap gradient compensates for depth-dependent variations in transport energetics. When the bandgap energy E.sub.BG(z) is increased for electrons with shorter path lengths to the emitting surface and decreased for electrons with longer path lengths to the emitting surface, such that the sum of E.sub.BG(z) and the scattering energy is substantially constant or similar for electrons photoexcited at all locations within the photocathode, the energies of the emitted electrons may be more similar (have less variability), and the emittance of the electron beam may be desirably decreased. The photocathode may be formed of a III-V semiconductor such as InGaN or an oxide semiconductor such as GaInO.

According to an embodiment of the present disclosure, a photocathode may include: a mesh having a first surface and a second surface facing away from the first surface, and including metallic, semiconductor or ceramic mesh grid with micron-sized openings in the mesh; a photosensitive film on the first surface of the mesh and extending at least partially into the openings of the mesh; and a graphene layer including one or more graphene sheets on the second surface of the mesh.

According to an embodiment of the present disclosure, a photocathode may include: a mesh having a first surface and a second surface facing away from the first surface, and including metallic, semiconductor or ceramic mesh grid with micron-sized openings in the mesh; a photosensitive film on the first surface of the mesh and extending at least partially into the openings of the mesh; and a graphene layer including one or more graphene sheets on the second surface of the mesh.

A microchannel plate is provided with a substrate including a front surface, a rear surface, and a side surface, a plurality of channels penetrating from the front surface to the rear surface of the substrate, a first film provided on at least an inner wall surface of the channel, a second film provided on the first film, and electrode layers provided on the front surface and the rear surface of the substrate. The first film is made of Al.sub.2O.sub.3. The second film is made of SiO.sub.2. The first film is thicker than the second film.

A microchannel plate is provided with a substrate including a front surface, a rear surface, and a side surface, a plurality of channels penetrating from the front surface to the rear surface of the substrate, a first film provided on at least an inner wall surface of the channel, a second film provided on the first film, and electrode layers provided on the front surface and the rear surface of the substrate. The first film is made of Al.sub.2O.sub.3. The second film is made of SiO.sub.2. The first film is thicker than the second film.

A method for creating an enhanced multipaction resistant diamond-like coating (DLC) coating with lower Secondary Electron Emission (SEE) properties is performed on an initial surface by etching a DLC coating deposited on the surface after deposition and optionally creating interlayers to enhance adhesion mechanical properties between the DLC coating and the initial surface.

An electron multiplier production method including a main body portion, and a channel provided in the main body portion to open at one end surface and the other end surface of the main body portion and emits secondary electrons includes a first step of preparing a main body member including the one end surface and the other end surface, a communicating hole for the channel through which the one end surface and the other end surface communicate being provided in the main body member, a second step of forming the channel by forming a deposition layer including at least a resistive layer on an outer surface of the main body member and an inner surface of the communicating hole using an atomic layer deposition method, and a third step of forming the main body portion by removing the deposition layer formed on the outer surface of the main body member.

An electron multiplier production method including a main body portion, and a channel provided in the main body portion to open at one end surface and the other end surface of the main body portion and emits secondary electrons includes a first step of preparing a main body member including the one end surface and the other end surface, a communicating hole for the channel through which the one end surface and the other end surface communicate being provided in the main body member, a second step of forming the channel by forming a deposition layer including at least a resistive layer on an outer surface of the main body member and an inner surface of the communicating hole using an atomic layer deposition method, and a third step of forming the main body portion by removing the deposition layer formed on the outer surface of the main body member.