United States of America As Represented by the Administrator of Nasa

National Institute of Aerospace Associates

Gachon University of Medicine & Science Industry-academic Cooperation Foundation

Other

The United States of America As Represented by the Administrator of the

Sang Hyouk Choi

Yeonjoon Park

Glen C King

James R Elliott

Adam J Duzik

Jae-Woo Kim

Dennis M Bushnell

Hyun Jung Kim

Sang-Hyon Chu

Peter T Lillehei

Kunik Lee

Cheol Park

Diane M Stoakley

Uhn Lee

Hyun-Jung Kim

Albert L Dimarcantonio

David R Komar

Robert C Hendricks

Joycelyn S Harrison

Robert W Moses

Yeon Joon Park

Noel A Talcott

Ronald J Litchford

Jonathan R Skuza

Methods and systems that enable growing a SiGe film at relative high temperature resulting in single crystalline properties and imparting twin crystal structures and/or dislocation to the SiGe film through either in-situ or ex-situ electron-beam irradiation. The various embodiments may maintain (or increase) the Seeback coefficient and electrical conductivity of thermoelectric materials and simultaneously decrease the thermal conductivity of the thermoelectric materials.

Growth method of highly twinned SiGe alloy on the basal plane of trigonal substrate under electron beam irradiation

The present disclosure is directed to a system including a nuclear thermal rocket or a nuclear reactor, at least one nuclear electric thruster coupled to the nuclear thermal rocket or the nuclear reactor, and a Nuclear Thermionic Avalanche Cell (NTAC) configured to generate electrical power. The NTAC cell may be positioned around a nuclear reactor core of the nuclear thermal rocket or the nuclear reactor, and the nuclear electric thruster may be powered by the NTAC generated electrical power.

NTAC augmented nuclear electric propulsion and/or nuclear thermal propulsion

Various aspects include electric generators configured to boost electrical output by leveraging electron avalanche generated by a high energy photon radiation source. In various aspects, an electric generator includes a stator and a rotor positioned within the stator, wherein the stator and rotor are configured to generate electric current when the rotor is rotated, and a high energy photon source (e.g., a gamma ray source) positioned and configured to irradiate at least a portion of conductors in the rotor or stator. In some aspects, the stator generates a magnetic field when the electric generator is operating, and the rotor includes armature windings configured to generate electric current when the rotor is rotated. In some aspects, the high energy photon source includes cobalt-60 and/or cesium-137.

High performance electric generators boosted by nuclear electron avalanche (NEA)

A metal junction thermoelectric device includes at least one thermoelectric element. The thermoelectric element has first and second opposite sides, and a first conductor made from a first metal, and a second conductor made from a second metal. The first and second conductors are electrically interconnected in series, and the first and second conductors are arranged to conduct heat in parallel between the first and second sides. The first metal has a first occupancy state, and the second metal has a second occupancy state that is lower than the first occupancy state. A temperature difference between the first and second sides of the thermoelectric element causes a charge potential due to the difference in occupancy states of the first and second metals. The charge potential generates electrical power.

Metallic junction thermoelectric generator

Some aspects relate to methods of forming an epitaxial layer. In some examples, the methods include ejecting atoms from a molten metal sputtering material onto a heated crystalline substrate and growing a single epitaxial layer on the substrate from the ejected atoms, where the atoms are ejected with sufficient energy that the grown epitaxial layer has at least a partial rhombohedral lattice, and wherein the crystalline substrate is heated to a temperature of about 600 degrees Celsius or less, or about 500 degrees or less. Other aspects relate to materials, such as a material including a single epitaxial layer on top of a crystalline substrate, the layer including one or more semiconductor materials and having at least a partial rhombohedral lattice, or a substantially rhombohedral lattice.

Single crystal epitaxial layer having a rhombohedral lattice

A thermionic (TI) power cell includes a heat source, such as a layer of radioactive material that generates heat due to radioactive decay, a layer of electron emitting material disposed on the layer of radioactive material, and a layer of electron collecting material. The layer of electron emitting material is physically separated from the layer of electron collecting material to define a chamber between the layer of electron collecting material and the layer of electron emitting material. The chamber is substantially evacuated to permit electrons to traverse the chamber from the layer of electron emitting material to the layer of electron collecting material. Heat generated over time by the layer of radioactive material causes a substantially constant flow of electrons to be emitted by the layer of electron emitting material to induce an electric current to flow through the layer of electron collecting material when connected to an electrical load.

Thermionic power cell

The present disclosure is directed to a nuclear thermionic avalanche cell (NTAC) systems and related methods of generating energy comprising a radioisotope core, a plurality of thin-layered radioisotope sources configured to emit high energy beta particles and high energy photons, and a plurality of NTAC layers integrated with the radioisotope core and the radioisotope sources, wherein the plurality of NTAC layers are configured to receive the beta particles and the photons from the radioisotope core and sources, and by the received beta particles and photons, free up electrons in an avalanche process from deep and intra bands of an atom to output a high density avalanche cell thermal energy through a photo-ionic or thermionic process of the freed up electrons.

Multi-layered radio-isotope for enhanced photoelectron avalanche process

The present disclosure is directed to nuclear thermionic avalanche cell (NTAC) systems and related methods of generating energy from captured high energy photons. Huge numbers of electrons in the intra-band of atom can be liberated through bound-to-free transition when coupled with high energy photons. If a power conversion process effectively utilizes these liberated electrons in an avalanche form through a power conversion circuit, the power output will be drastically increased. The power density of a system can be multiplied by the rate of high energy photon absorption. The present disclosure describes a system and methods built with multilayers of nuclear thermionic avalanche cells for the generation of energy. The multilayer structure of NTAC devices offers effective recoverable means to capture and harness the energy of gamma photons for useful purposes such as power systems for deep space exploration.

Multi-layer structure of nuclear thermionic avalanche cells

Systems, methods, and devices of the various embodiments provide for microfabrication of devices, such as semiconductors, thermoelectric devices, etc. Various embodiments may include a method for fabricating a device, such as a semiconductor (e.g., a silicon (Si)-based complementary metal-oxide-semiconductor (CMOS), etc.), thermoelectric device, etc., using a mask. In some embodiments, the mask may be configured to allow molecules in a deposition plume to pass through one or more holes in the mask. In some embodiments, molecules in a deposition plume may pass around the mask. Various embodiments may provide thermoelectric devices having metallic junctions. Various embodiments may provide thermoelectric devices having metallic junctions rather than junctions formed from semiconductors.

Selective and direct deposition technique for streamlined CMOS processing

Systems, methods, and devices of the various embodiments may provide a mechanism to enable the growth of a rhombohedral epitaxy at a lower substrate temperature by energizing the atoms in flux, thereby reducing the substrate temperature to a moderate level. In various embodiments, sufficiently energized atoms provide the essential energy needed for the rhombohedral epitaxy process which deforms the original cubic crystalline structure approximately into a rhombohedron by physically aligning the crystal structure of both materials at a lower substrate temperature.

Electron beam heating and atomic surface restructuring of sapphire surface

Systems, methods, and devices of the various embodiments enable a Nuclear Thermionic Avalanche Cell (NTAC) to capture gamma ray photons emitted during a fission process, such as a fission process of Uranium-235 (U-235), and to breed and use a new gamma ray source to increase an overall emission flux of gamma ray photons. Various embodiments combine a fission process with the production of Co-60, thereby boosting the output flux of gamma ray photons for use by a NTAC in generating power. Various embodiments combine a fission process with the production of Co-60, a NTAC generating avalanche cell power, and a thermoelectric generator generating thermoelectric power.

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Poquoson, VA, United States of America

Sang Hyouk Choi