Abstract: A high-throughput method for identifying single crystal hexagonal-SiC off-axis surfaces that support surface chemistries and kinetics to selectively produce various epitaxial growth modes of the metastable 3C-SiC polytype is provided. In execution of the aforementioned method, the present invention also encompasses the use of a single crystal hexagonal-SiC domed substrate, and a method for manufacturing thereof. Said method for screening silicon carbide growth surfaces is comprised of: fabrication of a silicon carbide domed substrate; forming a step-terrace growth surface on the domed surface of said silicon carbide domed substrate by hydrogen etching; performing silicon carbide deposition upon said growth surface, thereby creating an silicon carbide epitaxial domed wafer; and characterization of said silicon carbide epitaxial domed wafer. Silicon carbide deposition upon a silicon carbide domed growth surface allows for the modulation of the supersaturation ratio under a single set of growth conditions.

Abstract: A high-throughput method for identifying single crystal hexagonal-SiC off-axis surfaces that support surface chemistries and kinetics to selectively produce various epitaxial growth modes of the metastable 3C-SiC polytype is provided. In execution of the aforementioned method, the present invention also encompasses the use of a single crystal hexagonal-SiC domed substrate, and a method for manufacturing thereof. Said method for screening silicon carbide growth surfaces is comprised of: fabrication of a silicon carbide domed substrate; forming a step-terrace growth surface on the domed surface of said silicon carbide domed substrate by hydrogen etching; performing silicon carbide deposition upon said growth surface, thereby creating an silicon carbide epitaxial domed wafer; and characterization of said silicon carbide epitaxial domed wafer. Silicon carbide deposition upon a silicon carbide domed growth surface allows for the modulation of the supersaturation ratio under a single set of growth conditions.

Abstract: 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.

Abstract: 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.

Abstract: A high-throughput method for identifying single crystal hexagonal-SiC off-axis surfaces that support surface chemistries and kinetics to selectively produce various epitaxial growth modes of the metastable 3C-SiC polytype is provided. In execution of the aforementioned method, the present invention also encompasses the use of a single crystal hexagonal-SiC domed substrate, and a method for manufacturing thereof. Said method for screening silicon carbide growth surfaces is comprised of: fabrication of a silicon carbide domed substrate; forming a step-terrace growth surface on the domed surface of said silicon carbide domed substrate by hydrogen etching; performing silicon carbide deposition upon said growth surface, thereby creating an silicon carbide epitaxial domed wafer; and characterization of said silicon carbide epitaxial domed wafer. Silicon carbide deposition upon a silicon carbide domed growth surface allows for the modulation of the supersaturation ratio under a single set of growth conditions.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Systems, methods, and devices of the various embodiments may provide a portable power system for powering small devices that may be small, may be compact, may provide continuous power, and may be lightweight enough for an astronaut to carry. Various embodiments may provide a compact, thermionic-based cell that provides increased energy density and that more efficiently uses a heat source, such as a Pu-238 heat source. Nanometer scale emitters, spaced tightly together, in various embodiments convert a larger amount of heat into usable electricity than in current thermoelectric technology. The emitters of the various embodiments may be formed from various materials, such as copper (Cu), silicon (Si), silicon-germanium (SiGe), and lanthanides. Various embodiments may be added to regenerative thermionic cells with multiple layers to enhance the energy conversion efficiency of the regenerative thermionic cells.

Abstract: 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.

Abstract: 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.