A field emission transistor includes a gate, a fold over emitter, and fold over collector. The emitter and the collector are separated from the gate by a void and are separated from a gate contact by gate contact dielectric. The void may be a vacuum, ambient air, or a gas. Respective ends of the emitter and the collector are separated by a gap. Electrons are drawn across gap from the emitter to the collector by an electrostatic field created when a voltage is applied to the gate. The emitter and collector include a first conductive portion substantially parallel with gate and a second conductive portion substantially perpendicular with gate. The second conductive portion may be formed by bending a segment of the first conductive portion. The second conductive portion is folded inward from the first conductive portion towards the gate. Respective second conductive portions are generally aligned.

A field emission transistor includes a gate, a fold over emitter, and fold over collector. The emitter and the collector are separated from the gate by a void and are separated from a gate contact by gate contact dielectric. The void may be a vacuum, ambient air, or a gas. Respective ends of the emitter and the collector are separated by a gap. Electrons are drawn across gap from the emitter to the collector by an electrostatic field created when a voltage is applied to the gate. The emitter and collector include a first conductive portion substantially parallel with gate and a second conductive portion substantially perpendicular with gate. The second conductive portion may be formed by bending a segment of the first conductive portion. The second conductive portion is folded inward from the first conductive portion towards the gate. Respective second conductive portions are generally aligned.

A vacuum channel transistor having a vertical gate-all-around (GAA) architecture provides high performance for high-frequency applications, and features a small footprint compared with existing planar devices. The GAA vacuum channel transistor features stacked, tapered source and drain regions that are formed by notching a doped silicon pillar using a lateral oxidation process. A temporary support structure is provided for the pillar during formation of the vacuum channel. Performance of the GAA vacuum channel transistor can be tuned by replacing air in the channel with other gases such as helium, neon, or argon. A threshold voltage of the GAA vacuum channel transistor can be adjusted by altering dopant concentrations of the silicon pillar from which the source and drain regions are formed.

An integrated vacuum microelectronic structure is described as having a highly doped semiconductor substrate, a first insulating layer placed above said doped semiconductor substrate, a first conductive layer placed above said first insulating layer, a second insulating layer placed above said first conductive layer, a vacuum trench formed within said first and second insulating layers and extending to the highly doped semiconductor substrate, a second conductive layer placed above said vacuum trench and acting as a cathode, a third metal layer placed under said highly doped semiconductor substrate and acting as an anode, said second conductive layer is placed adjacent to the upper edge of said vacuum trench, the first conductive layer is separated from said vacuum trench by portions of said second insulating layer and is in electrical contact with said second conductive layer.

A vacuum channel transistor having a vertical gate-all-around (GAA) architecture provides high performance for high-frequency applications, and features a small footprint compared with existing planar devices. The GAA vacuum channel transistor features stacked, tapered source and drain regions that are formed by notching a doped silicon pillar using a lateral oxidation process. A temporary support structure is provided for the pillar during formation of the vacuum channel. Performance of the GAA vacuum channel transistor can be tuned by replacing air in the channel with other gases such as helium, neon, or argon. A threshold voltage of the GAA vacuum channel transistor can be adjusted by altering dopant concentrations of the silicon pillar from which the source and drain regions are formed.

In an embodiment, a method includes forming a first diamond layer on a substrate and inducing a layer of graphene from the first diamond layer by heating the substrate and the first diamond layer. The method includes forming a second diamond layer on top of the layer of graphene and applying a mask to the second diamond layer. The mask includes a shape of a cathode, an anode, and one or more grids. The method further includes forming a two-dimensional cold cathode, a two-dimensional anode, and one or more two-dimensional grids by reactive-ion electron-beam etching. Each of the two-dimensional cold cathode, the two-dimensional anode, and the one or more two-dimensional grids includes a portion of the first diamond layer, the graphene layer, and the second diamond layer such that the graphene layer is positioned between the first diamond layer and the second diamond layer.

A vacuum integrated electronic device has an anode region of conductive material; an insulating region on top of the anode region; a cavity extending through the insulating region and having a sidewall; and a cathode region. The cathode region has a tip portion extending peripherally within the cavity, adjacent to the sidewall of the cavity. The cathode region is formed by tilted deposition, carried out at an angle of 30-60 with respect to a perpendicular to the surface of device.

Vacuum transistors with carbon nanotube as the collector and/or emitter electrodes are provided. In one aspect, a method for forming a vacuum transistor includes the steps of: covering a substrate with an insulating layer; forming a back gate(s) in the insulating layer; depositing a gate dielectric over the back gate; forming a carbon nanotube layer on the gate dielectric; patterning the carbon nanotube layer to provide first/second portions thereof over first/second sides of the back gate, separated from one another by a gap G, which serve as emitter and collector electrodes; forming a vacuum channel in the gate dielectric; and forming metal contacts to the emitter and collector electrodes. Vacuum transistors are also provided.

Vacuum transistors with carbon nanotube as the collector and/or emitter electrodes are provided. In one aspect, a method for forming a vacuum transistor includes the steps of: covering a substrate with an insulating layer; forming a back gate(s) in the insulating layer; depositing a gate dielectric over the back gate; forming a carbon nanotube layer on the gate dielectric; patterning the carbon nanotube layer to provide first/second portions thereof over first/second sides of the back gate, separated from one another by a gap G, which serve as emitter and collector electrodes; forming a vacuum channel in the gate dielectric; and forming metal contacts to the emitter and collector electrodes. Vacuum transistors are also provided.

A vacuum integrated electronic device has an anode region of conductive material; an insulating region on top of the anode region; a cavity extending through the insulating region and having a sidewall; and a cathode region. The cathode region has a tip portion extending peripherally within the cavity, adjacent to the sidewall of the cavity. The cathode region is formed by tilted deposition, carried out at an angle of 30-60 with respect to a perpendicular to the surface of device.