A cathode of an electron emitting device is described, where the cathode comprises a carbon nanotube (CNT); a nano-filler material; and a carbonizable polymer, and where the cathode exhibits increased hardness, is formed by high temperature thermal treatment, and is devoid of a substrate. Also described is a method of forming a cathode of an electron emitting device, where the method comprises a) forming a dispersed mixture comprising a carbon nanotube, a nano-filler material, and a carbonizable polymer in a solvent; b) coating and/or extruding the mixture; c) drying the coated and/or extruded mixture to remove at least a substantial portion of the solvent; and d) subjecting the dried mixture to a high temperature thermal treatment; where the method results in the cathode of an electron emitting device having increased hardness.

Nanoscale field-emission devices are presented, wherein the devices include at least a pair of electrodes separated by a gap through which field emission of electrons from one electrode to the other occurs. The gap is dimensioned such that only a low voltage is required to induce field emission. As a result, the emitted electrons energy that is below the ionization potential of the gas or gasses that reside within the gap. In some embodiments, the gap is small enough that the distance between the electrodes is shorter than the mean-free path of electrons in air at atmospheric pressure. As a result, the field-emission devices do not require a vacuum environment for operation.

Electron emitters and methods of fabricating the electron emitters are disclosed. According to certain embodiments, an electron emitter includes a tip with a planar region having a diameter in a range of approximately (0.05-10) micrometers. The electron emitter tip is configured to release field emission electrons. The electron emitter further includes a work-function-lowering material coated on the tip.

A horizontal multilayer junction-edge field emitter includes a plurality of vertically-stacked multilayer structures separated by isolation layers. Each multilayer structure is configured to produce a 2-dimensional electron gas at a junction between two layers within the structure. The emitter also includes an exposed surface intersecting the 2-dimensional electron gas of each of the plurality of vertically-stacked multilayer structures to form a plurality of effectively one-dimensional horizontal line sources of electron emission.

The present application discloses an array substrate comprising a first substrate, a first electrode on the first substrate, a passivation layer on a side of the first electrode distal to the first substrate, the passivation layer comprising a plurality of first vias, each of which corresponds to a different part of the first electrode, an electron emission source layer on a side of the first electrode distal to the first substrate comprising at least one electron emission source in each of the plurality of first vias, and a dielectric layer on a side of the first electrode distal to the first substrate comprising a plurality of dielectric blocks corresponding to the plurality of first vias, at least a portion of each of the plurality of dielectric blocks in each of the plurality of first vias. The at least one electron emission source comprises a first portion having a first end and a second portion having a second end. The first end is in contact with the first electrode, the first portion is within a corresponding one of the plurality of dielectric blocks. The second portion and the second end are outside the corresponding one of the plurality of dielectric blocks.

A method for manufacturing a microelectronic semiconductor device comprising the steps of: forming a trench in a body, the trench having side walls, a opening, and a bottom; forming a sacrificial layer in the trench; forming a recess in the sacrificial layer; forming a restriction structure between the sacrificial layer and the opening of the trench, defining a through hole for access to the sacrificial layer; completely removing the sacrificial layer through said through hole; and depositing a metal layer over the body, thus closing the opening of the trench and forming an electron-emission cathode tip.

Nanoscale field-emission devices are presented, wherein the devices include at least a pair of electrodes separated by a gap through which field emission of electrons from one electrode to the other occurs. The gap is dimensioned such that only a low voltage is required to induce field emission. As a result, the emitted electrons energy that is below the ionization potential of the gas or gasses that reside within the gap. In some embodiments, the gap is small enough that the distance between the electrodes is shorter than the mean-free path of electrons in air at atmospheric pressure. As a result, the field-emission devices do not require a vacuum environment for operation.

An electron source emitter is made from transition metal carbide materials, including hafnium carbide (HfC), zirconium carbide (ZrC), titanium carbide (TiC), vanadium carbide (VC), niobium carbide (NbC), and tantalum carbide (TaC), which are of high refractory nature. Preferential evaporating and subsequent development of different crystallographic planes of the transition metal carbide emitter having initially at its apex a small radius (50 nm-300 nm) develop over time an on-axis, sharp end-form or tip that is uniformly accentuated circumferentially to an extreme angular form and persists over time. An emitter manufactured to the (110) crystallographic plane and operating at high electron beam current and high temperature for about 20 hours to 40 hours results in the (110) plane, while initially not a high emission crystallographic orientation, developing into a very high field emission orientation because of the geometrical change. This geometrical change allows for a very high electric field and hence high on-axis electron emission.

The emitter of the present invention includes a nanowire. The nanowire is formed from a hafnium carbide (HfC) single crystal, and at least an end portion of the hafnium carbide single crystal, from which electrons are to be emitted, is covered with hafnium oxide (HfO.sub.2). In the emitter, the thickness of the hafnium oxide may be 1 nm to 20 nm.

An emitter containing a metal boride material has an at least partly rounded tip with a radius of 1 m or less. An electric field can be applied to the emitter and an electron beam is generated from the emitter. To form the emitter, material is removed from a single crystal rod to form an emitter containing a metal boride material having a rounded tip with a radius of 1 m or less.