A field emission cathode device and formation method involves a rotating field emission cathode including a field emission material deposited on a surface thereof, the field emission cathode rotating about an axis and being electrically connected to ground, and a planar gate electrode extending parallel to the surface of the rotating field emission cathode and defining a gap therebetween. A gate voltage source is electrically connected to the gate electrode and is arranged to interact therewith to generate an electric field, with the electric field inducing a portion of the surface of the rotating field emission cathode adjacent to the gate electrode to emit electrons from the field emission material toward and through the gate electrode.

A field emission cathode device and formation method involves a rotating field emission cathode including a field emission material deposited on a surface thereof, the field emission cathode rotating about an axis and being electrically connected to ground, and a planar gate electrode extending parallel to the surface of the rotating field emission cathode and defining a gap therebetween. A gate voltage source is electrically connected to the gate electrode and is arranged to interact therewith to generate an electric field, with the electric field inducing a portion of the surface of the rotating field emission cathode adjacent to the gate electrode to emit electrons from the field emission material toward and through the gate electrode.

A field emission cathode device comprises a field emission cathode including a cylindrical substrate and a field emission material deposited on a cylindrical surface thereof. The field emission cathode defines a longitudinal axis. A solenoid extends concentrically about the cylindrical surface, and defines a gap therebetween. The solenoid defines opposed open ends perpendicular to the longitudinal axis. A current source directs a constant polarity (DC) current to the solenoid, that forms a magnetic field along the solenoid. A gate voltage source electrically connected to the solenoid or the field emission cathode interacts therewith to generate an electric field inducing the field emission cathode to emit electrons from the field emission material into the gap. The emitted electrons are responsive to the magnetic field to spiral within the gap and about the longitudinal axis, in correspondence with the current flow in the solenoid, through the first open end of the solenoid.

A field emission cathode device comprises a field emission cathode including a cylindrical substrate and a field emission material deposited on a cylindrical surface thereof. The field emission cathode defines a longitudinal axis. A solenoid extends concentrically about the cylindrical surface, and defines a gap therebetween. The solenoid defines opposed open ends perpendicular to the longitudinal axis. A current source directs a constant polarity (DC) current to the solenoid, that forms a magnetic field along the solenoid. A gate voltage source electrically connected to the solenoid or the field emission cathode interacts therewith to generate an electric field inducing the field emission cathode to emit electrons from the field emission material into the gap. The emitted electrons are responsive to the magnetic field to spiral within the gap and about the longitudinal axis, in correspondence with the current flow in the solenoid, through the first open end of the solenoid.

Provided is a method for manufacturing an electric field emission device. The method for manufacturing the electric field emission device includes winding a carbon nanotube yarn around outer circumferential surfaces of a metal plate in a first direction, pressing both side surfaces of the metal plate through a pair of metal structures, wherein a top surface of the metal plate is exposed from the metal structures, and an area of the top surface of the metal plate is less than that of each of both the side surfaces of the metal plate, and cutting the carbon nanotube yarn at an edge portion of the top surface of the metal plate in the first direction to form a plurality of emitters.

Provided is a method for manufacturing an electric field emission device. The method for manufacturing the electric field emission device includes winding a carbon nanotube yarn around outer circumferential surfaces of a metal plate in a first direction, pressing both side surfaces of the metal plate through a pair of metal structures, wherein a top surface of the metal plate is exposed from the metal structures, and an area of the top surface of the metal plate is less than that of each of both the side surfaces of the metal plate, and cutting the carbon nanotube yarn at an edge portion of the top surface of the metal plate in the first direction to form a plurality of emitters.

Gas discharge tube having glass seal. In some embodiments, a gas discharge tube can include an insulator layer having first and second sides and defining an opening, and first and second electrodes that cover the opening on the first and second sides of the insulator layer, respectively. The gas discharge tube can further include a first glass layer implemented between the first electrode and the first side of the insulator layer, and a second glass layer implemented between the second electrode and the second side of the insulator layer, such that the first and second glass layers provide a seal for a chamber defined by the opening and the first and second electrodes.

Vacuum electron devices (VEDs) having a plurality of two-dimensional layers of various materials are bonded together to form one or more VEDs simultaneously. The two-dimensional material layers are machined to include features needed for device operation so that when assembled and bonded into a three-dimensional structure, three-dimensional features are formed. The two-dimensional layers are bonded together into a sandwich-like structure. The manufacturing process enables incorporation of metallic, magnetic, ceramic materials, and other materials required for VED fabrication while maintaining required positional accuracy and multiple devices per batch capability.

Methods for fabricating gas discharge tubes. In some embodiments, a method for fabricating a gas discharge tube (GDT) device can include providing or forming an insulator substrate having first and second sides and defining an opening. The method can further include providing or forming a first electrode and a second electrode. The method can further include forming a first glass seal between the first electrode and the first side of the insulator substrate, and a second glass seal between the second electrode and the second side of the insulator substrate, such that the first and second glass seals provide a hermetic seal for a chamber defined by the opening and the first and second electrodes.

A device for controlling electron flow is provided. The device comprises a cathode, an elongate electrical conductor embedded in a diamond substrate, an anode, and a control electrode provided on the substrate surface for modifying the electric field in the region of the end of the conductor. A method of manufacturing the device is also provided.