Abstract: Thermoelectric material of (Bi, Sb)(Te, Se) system is produced through a liquid quenching method and an extrusion from a die unit having an inlet portion and an outlet portion crossing each other at 30-150 degrees so that the crystal grains have an average grain size equal to or less than 30 microns and (001) planes mostly oriented in parallel to a direction in which electric current to flow, thereby achieving the figure of merit equal to or greater than 3.0×10−3/K.

Abstract: It is an object of the present invention to provide a thermoelectric conversion material, and a thermoelectric conversion element that makes use of this material, which allow the Seebeck effect and the Nernst effect to be utilized synergistically, have a high Seebeck coefficient, and afford greater thermoelectromotive force.

Abstract: A process for producing a thermoelectric material comprising mixing at least two of bismuth, tellurium, selenium, and antimony and, if desired, a dopant, melting the mixture, grinding the resulting alloy ingot, forming the powder, and sintering the green body under normal pressure, or hot pressing the powder, wherein the grinding and the normal sintering or hot pressing are carried out in the presence of a solvent represented by CnH2n+1OH or CnH2n+2CO (wherein n is 1, 2 or 3).

Abstract: Ternary tellurium compounds and ternary selenium compounds may be used in fabricating thermoelectric devices with a thermoelectric figure of merit (ZT) of 1.5 or greater. Examples of such compounds include Tl2SnTe5, Tl2GeTe5, K2SnTe5 and Rb2SnTe5. These compounds have similar types of crystal lattice structures which include a first substructure with a (Sn, Ge) Te5 composition and a second substructure with chains of selected cation atoms. The second substructure includes selected cation atoms which interact with selected anion atoms to maintain a desired separation between the chains of the first substructure. The cation atoms which maintain the desired separation between the chains occupy relatively large electropositive sites in the resulting crystal lattice structure which results in a relatively low value for the lattice component of thermal conductivity (&kgr;g).

Abstract: A method of fabricating a thermoelectric element with a higher thermoelectric performance than that of a conventional thermoelectric element. This fabrication method includes the steps of: (a) preparing a thermoelectric material having a predetermined composition; and (b) applying extruding pressure to the thermoelectric material in a first direction to extrude it through a die having, in an area which is not less than half of a deforming area of the thermoelectric material in the first direction, a maximum strain rate within +30% of an average strain rate so as to plastically deform the thermoelectric material into an extruded product of the thermoelectric material.

Abstract: Improved Hg-containing superconducting films and thermoelectric materials are provided. The films are fabricated by annealing starting Tl-containing films (e.g., Tl-1212 or Tl-2212) in an Hg-vapor environment so as to cause a substitution of Tl by Hg without substantial alteration of the crystalline structure of the starting films. Preferably, a body comprising a substrate having an epitaxial Tl-containing film thereon is annealed under vacuum conditions with a Hg-based bulk; typical annealing conditions are 600-900° C. for a period of from about 1-20 hours. The final Hg-containing film products have a Jc of at least about 106 A/cm2 (100 K, OT) and a Xmin of up to about 50%. The thermoelectric materials are prepared by perturbing a crystalline precursor having a structure similar to the final material so as to cause a first molecule to be released from the precursor.

Abstract: A thermoelectric device with enhanced structured interfaces for improved cooling efficiency is provided. In one embodiment, the thermoelectric device includes a first thermoelement comprising a supetlattice of p-type thermoelectric material and a second thermoelement comprising superlattice of n-type thermoelectric material. The first and second thermoelements are electrically coupled to each other. The first thermoelement is proximate to, without necessarily being in physical contact with, a first array of electrically conducting tips at a discrete set of points. A planer surface of the second thermoelement is proximate to, without necessarily being in physical contact with, a second array of electrically conducting tips at a discrete set of points. The electrically conducting tips are coated with a material that has the same Seebeck coefficient as the material of the nearest layer of the superlattice to the tip.

Abstract: A thermoelectric module including a couple formed between two bismuth telluride thermoelectrodes. The first thermoelectrode is doped with palladium, selenium, or a combination of the two. The second thermoelectrode is doped with antimony, gold, or a combination of the two. Multiple thermoelectric modules may be used in series and parallel to achieve the desired voltage and current outputs.

Abstract: A class of thermoelectric compounds based on the skutterudite structure with heavy filling atoms in the empty octants and substituting transition metals and main-group atoms. High Seebeck coefficients and low thermal conductivities are achieved in combination with large electrical conductivities in these filled skutterudites for large ZT values. Substituting and filling methods are disclosed to synthesize skutterudite compositions with desired thermoelectric properties. A melting and/or sintering process in combination with powder metallurgy techniques is used to fabricate these new materials.

Abstract: An energy converting circuit, boosting the voltage supplied by a low direct voltage source, comprising a self-oscillating circuit, operating at very low voltage, using a voltage boosting transformer generating control signals of two chopper-boosters operating alternately. The circuit including an enhancement-type field effect translator used in synchronous switching with the self-oscillating circuit, which is in serial connection with an inductive resistor to the terminals of the source (1). The transistor being connected to a user circuit via a diode (15, 16). The circuit is used in a device for supplying electricity to appliances and by the production of thermal converters for the utilization of low-voltage thermoelectricity, as well as in a method for the manufacture of thermal converters on an industrial scale.

Abstract: A family of isostructural compounds have been prepared having the general formula AnPbmBinQ2n+m. These compounds possess a NaCl lattice type structure as well as low thermal conductivity and controlled electrical conductivity. Furthermore, the electrical properties can be controlled by varying the values for n and m. These isostructural compounds can be used for semiconductor applications such as detectors, lasers and photovoltaic cells. These compounds also have enhanced thermoelectric properties making them excellent semiconductor materials for fabrication of thermoelectric devices.

Abstract: Thermoelectric materials having a high performance index and thermoelectric elements are provided. The present thermoelectric materials are constituted by at least one element selected from the group consisting of Bi and Sb, at least one element selected from the group consisting of Te and Se, and, if necessary, at least one element selected from the group consisting of I, Cl, Hg, Br, Ag, and Cu. The long axis of each crystal grain of the thermoelectric material grows in the direction parallel to the pressing direction at the time of press formation, and the aspect ratio D/d of each crystal grain, which represents a ratio between the average crystal grain size along the long axis D to the average crystal grain size along the short axis d, is more than 1.5. The C-plane is oriented parallel to the pressing direction.

Abstract: A device for generating power to run an electronic component. The device includes a heat-conducting substrate (composed, e.g., of diamond or another high thermal conductivity material) disposed in thermal contact with a high temperature region. During operation, heat flows from the high temperature region into the heat-conducting substrate, from which the heat flows into the electrical power generator. A thermoelectric material (e.g., a Bi2Te3-based film or other thermoelectric material) is placed in thermal contact with the heat-conducting substrate. A low temperature region is located on the side of the thermoelectric material opposite that of the high temperature region. The thermal gradient generates electrical power and drives an electrical component.

Abstract: A thermoelectric semiconductor material having sufficient strength and performance and high production yield. The thermoelectric semiconductor material is characterized in that a sintered powder material of a thermoelectric semiconductor having a rhombohedral structure (or hexagonal structure) is hot-forged and plastically deformed to direct either the crystals of the sintered powder structure or the subcrystals constructing the crystals in a crystal orientation having an excellent figure of merit.

Abstract: A p-type thermoelectric converting substance used as a p-type semiconductor in a thermoelectric converting module consisting essentially of a substance expressed by a chemical formula CoSbxSny or CoSbxGey (2.7<x<3.4, 0<y<0.4, x+y>3), and containing a small amount of oxygen z defined by 2(x+y−3)≧z. The amount of oxygen z is preferably limited such that it is not higher than 0.1 molecules per 1 molecule of Co. An alloy ingot consisting essentially of CoSbxSny or CoSbxGey (2.7<x<3.4, 0<y<0.4, x+y>3) is ground to obtain a raw material powder. Then, the powder is cast into a mold, and the mold is sintered under a non-oxidizing or reducing atmosphere. The thus obtained substance reveals p-conductivity in a stable manner over a wide temperature range, and has excellent thermoelectric converting properties.

Abstract: An improved material for a thermoelectric device and thermoelectric systems incorporating the same.

Abstract: A thermoelectric semiconductor compound is provided whose performance index Z is remarkably improved without sacrificing Seebeck coefficient, electrical conductivity or thermal conductivity. The thermoelectric semiconductor compound includes a first thermoelectric semiconductor which is in the form of matrix and a second thermoelectric semiconductor which is in the form of particles dispersed in the matrix. The first thermoelectric semiconductor and the second thermoelectric semiconductor have a common element. The average diameter D of the dispersed particles complies with a formula of A<D<B, where A is the mean free path of a carrier in a single crystal of the second thermoelectric semiconductor and B is the mean free path of a long wave length phonon in the single crystal of the second thermoelectric semiconductor. A method for making the a thermoelectric semiconductor compound is provided.

Abstract: A miniature thermoelectric module for generating electric power from low power heat sources in the range of a fraction of a Watt to a few Watts. The module comprises an array of thermoelectric elements, each element having a cross section of less than 0.001 square inch and a length of at least 0.25 inch. The elements are separated from each other with a polyimide insulator sheet in a checkerboard array. In a preferred embodiment, the modules are fabricated by hot pressing a stack of alternating plates of p and n doped thin plates all separated by thin sheets of a polyimide insulator material to produce a pressed stack of p and n doped layers. The stack is then sliced to produce layered plates which are then stacked with insulating polyimide layers positioned between the layered plates to produce the checkerboard array of p and n thermoelectric elements. Contacts are applied to electrically connect all of the elements.

Abstract: The present invention relates to a skutterudite thermoelectric material for directly converting heat generated by the Seebeck effect into electricity, and provides a method of producing a Co—Sb-based filled-skutterudite sintered material having a lower thermal conductivity and thereby having a higher figure of merit. The crystal grains of a Sb-containing skutterudite compound and a metal oxide dispersed in the crystal grain boundaries are sintered to obtain the skutterudite thermoelectric sintered material. The metal oxide prevents growth of grains in the process of sintering, whereby the skutterudite compound is finely pulverized to have an average crystal grain size of 20 &mgr;m or less. As a result, the areas at the boundaries of the fine crystal grains are increased, phonon scattering is enhanced, the thermal conductivity is decreased, and the figure of merit is increased. The metal oxide is an oxide of a rare earth metal.

Abstract: The present invention allows optimum filling of void spaces typically found in skutterudite type crystal lattice structures associated with various semiconductor materials. Selective filling of such void spaces in the associated lattice structure provides semiconductor materials which are particularly beneficial for use in fabricating thermoelectric devices for electrical power generation and/or cooling applications. By selectively filling a portion of the void spaces associated with skutterudite type crystal lattice structure, reductions in thermal conductivity of the resulting semiconducting material may be optimized while at the same time minimizing any reduction in electrical properties of the resulting semiconductor materials, which results in maximizing the thermoelectric figure of merit for the associated thermoelectric device.

Abstract: The present invention allows optimum filling of cavities or cages typically found in crystal lattice type structures associated with an inclusion complex such as formed by clathrate compounds. Filling such cavities or cages in the associated crystal lattice type structure provides semiconductor materials which are particularly beneficial for use in fabricating thermoelectric devices for electrical power generation and/or cooling applications. By filling the cavities or cages associated with clathrate compounds with selected metal and/or semi-metal atoms, reductions in thermal conductivity may be optimized while at the same time minimizing any reduction in electrical properties of the resulting semiconductor materials. As a result, the thermoelectric Figure of Merit for a thermoelectric device fabricated from such clathrate compounds is maximized.

Abstract: A process for producing a sintered thermoelectric semiconductor includes a first step of forming bulk crystals of a thermoelectric semiconductor and a second step of hot extrusion. The second step includes substeps of placing the bulk crystals in the cavity of a heated extrusion die, pushing the ram into the cavity, thereby compressing and crushing the bulk crystals and turning them into a molten or semi-molten state, and finally extruding the molten or semi-molten crystals, thereby sintering them and forming a sintered thermoelectric semiconductor.

Abstract: A method and apparatus for generating electrical power using animal body heat as the sole energy source. The apparatus includes a plurality of thermocouples connected in series and thermal insulating material for retaining heat in the hot junction and thermal conducting material for conducting heat away from the cold junction whereby a temperature differential between the hot and cold junctions of the thermocouples is maintained body heat energy received by the hot junction is converted to electrical power. The apparatus can be used to replace or supplement the electrical power provided by a low-voltage battery to drive a microelectronic device.

Abstract: Current leads are used for connecting a power supply placed in a room-temature environment and a superconducting coil placed in an ultralow-temperature environment. The current leads includes a first current lead and a second current lead. The first current lead is made up of a room-temperature N-type thermoelectric semiconductor, a low-temperature N-type thermoelectric semiconductor, and a high-temperature superconductor. The second current lead is made up of a room-temperature P-type thermoelectric semiconductor, a low-temperature P-type thermoelectric semiconductor, and a high-temperature superconductor. At least one of the first and second current leads is formed of a functionally gradient material.

Abstract: A class of thermoelectric compounds based on the skutterudite structure with heavy filling atoms in the empty octants and substituting transition metals and main-group atoms. High Seebeck coefficients and low thermal conductivities are achieved in combination with large electrical conductivities in these filled skutterudites for large ZT values. Substituting and filling methods are disclosed to synthesize skutterudite compositions with desired thermoelectric properties. A melting and/or sintering process in combination with powder metallurgy techniques is used to fabricate these new materials.

Abstract: Thermodynamically metastable skutterudite crystalline-structured compounds are disclosed having preselected stoichiometric compositions and superior and optimizable thermoelectric properties. The compounds are formed at low nucleation temperatures and satisfy the formula:M.sub.1-x M'.sub.4-y Co.sub.y M".sub.12wherein:M=any metal, metalloid, or mixture thereof, except for La, Ce, Pr, Nd, and Eu when x=0, and M'=Fe, Ru, or Os, and M"=Sb, P, or As;M'=Fe, Ru, Os, Rh, or mixture thereof;M"Sb, As, P, Bi, Ge.sub.0.5-w Se.sub.0.5+w, wherein w=0 to 0.5 or mixture thereof;x=0 to 1;y=0 to 4; andwherein M' and/or M" are doped or undoped. These compounds generally have the crystalline structure of a skutterudite, wherein the crystalline structure is cubic with 34 atoms in the unit-cell in the space group Im3. The M".sub.12 atoms occupy unit-cell sites 24(g), the M'.sub.4-y atoms form a cubic sublattice occupying unit-cell sites 8(c), and the M.sub.

Abstract: Molten thermoelectric alloy expressed as (Bi, Sb).sub.2 (Te, Se).sub.3 is rapidly cooled at 10.sup.4 to 10.sup.6 .degree. K/second so as to crystallize the thermoelectric alloy, and powder of the thermoelectric alloy is hot pressed under the pressure equal to or greater than 400 kgf/cm.sup.2 at 200 degrees to 400 degrees in centigrade for a time period between {(-T/5)+90} minutes and 150 minutes or at 400 degrees to 500 degrees in centigrade for a time period between 5 minutes and 150 minutes so as to increase the figure of merit by virtue of the strain left in the crystal and/or micro crystal grain.

Abstract: A thermoelectric conversion material includes a sintered body composed mainly of cobalt and antimony, wherein cobalt and antimony as main components form a compound of cubic CoSb.sub.3, a phase composed mainly of an Sb phase is contained as a secondary phase, and a volumetric rate of the phase closed mainly of the Sb phase is less than 10 vol % with respect to 100 vol % of the thermoelectric conversion material.

Abstract: A thermovoltaic energy conversion device and related method for converting thermal energy into an electrical potential. An interference filter is provided on a semiconductor thermovoltaic cell to pre-filter black body radiation. The semiconductor thermovoltaic cell includes a P/N junction supported on a substrate which converts incident thermal energy below the semiconductor junction band gap into electrical potential. The semiconductor substrate is doped to provide a plasma filter which reflects back energy having a wavelength which is above the band gap and which is ineffectively filtered by the interference filter, through the P/N junction to the source of radiation thereby avoiding parasitic absorption of the unusable portion of the thermal radiation energy.

Abstract: The present invention relates to a thermoelectric material containing CoSb.sub.3 compound for converting heat to electricity, and provides a p-type thermoelectric material of CoSb.sub.3 having a high power factor by achieving high Seebeck coefficient consistently with high electric conductivity in a material of CoSb.sub.3 system without causing increase in heat conductivity. By sintering Co.sub.0.07 Pt.sub.0.03 Sb.sub.3 alloy powder using the spark plasma sintering technique, the material is densified, while growth of grains is restricted, so that a higher electric conductivity is achieved with a heat conductivity maintained in a low level, and the figure of merit as a heat-transfer material is improved. Also, by providing such heat insulating layer as an oxide intermediately in a grain boundary of a compound of CoSb.sub.3 in a sintered body, the heat conductivity is reduced. Further, the Seebeck coefficient is increased by adding a rare earth metal to the thermoelectric material of CoSb.sub.

Abstract: A thermoelectric material which exhibits an excellent thermoelectric performance even when it is used at elevated temperatures is shown and described. A thermoelectric material is provided having conductive layers made of a first semiconductor only, and barrier layers made of a second semiconductor only, that are alternatingly formed one upon the other. The interface of the barrier layer relative to the conductive layer is roughly formed to include a plurality of protuberances and a plurality of recesses, and the interface of the conductive layer relative to the barrier layer is roughly formed to fit the interface of the barrier layer. The ratio Ry/t of the maximum height Ry of the protuberance on the barrier layer to the thickness t of the barrier layer is set to be Ry/t.gtoreq.0.1. This makes it possible to enhance the strength of the heterojunction interface between the barrier layer and the conductive layer and to improve the heat resistance.

Abstract: Thermoelectric material for high temperature use made of a sintered body of a relative density of at least 75% consisting mainly of cobalt antimony compounds having an elemental ratio Sb/(Co+additives)=x of 2.7<x<3 is produced by a method of firing a shaped body of powders consisting mainly of cobalt and antimony in a non-oxidizing atmosphere under an environmental pressure, wherein the shaped body before the firing is constituted from crystal phases composed of a cubic crystal system compound CoSb.sub.3 (A phase), a monoclinic crystal system compound CoSb.sub.2 (B phase) and a hexagonal crystal system compound CoSb (C phase), and constitutional ratio of these crystal phases is (I.sub.B +I.sub.C)/(I.sub.A +I.sub.B +I.sub.C)<0.15 (wherein, I.sub.X (X is A, B or C) is a relative intensity by X-ray diffraction).

Abstract: A superlattice structure comprising alternating layers of material such as (PbEuTeSe).sub.m and (BiSbn).sub.n where m and n are the number of PbEuTeSe and BiSb monolayers per superlattice period. For one superlattice structure the respective quantum barrier layers may be formed from electrical insulating material and the respective quantum well layers may be formed from semimetal material. For some applications superlattice structures with 10,000 or more periods may be grown. For example, the superlattice structure may comprise alternating layers of (Pb.sub.1-y Eu.sub.y Te.sub.1-z Se.sub.z).sub.m and (Bi.sub.x Sb.sub.1-x).sub.n. According to one embodiment, the superlattice structure may comprise a plurality of layers comprising m layers of (Pb.sub.1-y Eu.sub.y Te.sub.1-z Se.sub.z).sub.m and n layers of Bi.sub.0.9 Sb.sub.0.1, where m and n are preferably between 2 and 20, grown on a BaF.sub.2 substrate with a buffer layer of PbTe separating the substrate and the superlattice structure.

Abstract: A thermoelectric material which exhibits a high thermoelectric performance even at high temperatures is shown and described. A thermoelectric material is provided with a plurality of conductive layers made of a first semiconductor only and a plurality of barrier layers made of a second semiconductor only, which are alternatingly arranged, a diffusion-preventive layer being interposed between neighboring conductive layers and barrier layers. Diffusion between the conductive layers and the barrier layers under high-temperature conditions is prevented, and the thermoelectric material maintains high performance standards at high temperatures.

Abstract: A thermoelectric material having excellent thermoelectric performance is shown and described. A thermoelectric material is formed having a plurality of conductive layers and a plurality of barrier layers that are alternatingly formed one upon the other such that one conductive layer is sandwiched by two barrier layers. The conductive layers are composed of a first semiconductor only, and the two barrier layers located on the outermost sides of the material each have a main layer made of a second semiconductor only and a boundary layer made of the first and second semiconductors. A plurality of barrier layers positioned in between the conductive layers each have a main layer and two boundary layers provided on opposite sides of the main layer. The thickness t.sub.1 of the conductive layer and the thickness t.sub.2 of the barrier layer have a relationship of 2t.sub.1 .ltoreq.t.sub.2 .ltoreq.50t.sub.1.

Abstract: A thermoelectric device is provided which is good in terms of responsibility to heat, by which a relatively large electric power can be produced, which is good in terms of durability, and which can be manufactured at reduced cost. The thermoelectric device includes a substrate having a thickness of 2.0 mm or less, and a thick-film type thermoelectric material formed on the substrate, and having a thickness of from 0.01 mm to 1.0 mm. The thick-film type thermoelectric material is covered with a glassy coating. By the coating, the thick-film type thermoelectric material is inhibited from coming off, and from deteriorating oxidatively.

Abstract: New skutterudite phases including Ru.sub.0.5 Pd.sub.0.5 Sb.sub.3, RuSb.sub.2 Te, and FeSb.sub.2 Te, have been prepared having desirable thermoelectric properties. In addition, a novel thermoelectric device has been prepared using skutterudite phase Fe.sub.0.5 Ni.sub.0.5 Sb.sub.3. The skutterudite-type crystal lattice structure of these semiconductor compounds and their enhanced thermoelectric properties results in semiconductor materials which may be used in the fabrication of thermoelectric elements to substantially improve the efficiency of the resulting thermoelectric device. Semiconductor materials having the desired skutterudite-type crystal lattice structure may be prepared in accordance with the present invention by using powder metallurgy techniques. Measurements of electrical and thermal transport properties of selected semiconductor materials prepared in accordance with the present invention, demonstrated high Hall mobilities and good Seebeck coefficients.

Abstract: Thermoelectric material contains one or more than one element selected from the transition metals and the rare earth metals, and the element promotes the amorphous phase in the thermoelectric material so as to increase the figure of merit.

Abstract: A cooling device for lowering the temperature of a heat-dissipating device. The cooling device includes a heat-conducting substrate (composed, e.g., of diamond or another high thermal conductivity material) disposed in thermal contact with the heat-dissipating device. During operation, heat flows from the heat-dissipating device into the heat-conducting substrate, where it is spread out over a relatively large area. A thermoelectric cooling material (e.g., a Bi.sub.2 Te.sub.3 -based film or other thermoelectric material) is placed in thermal contact with the heat-conducting substrate. Application of electrical power to the thermoelectric material drives the thermoelectric material to pump heat into a second heat-conducting substrate which, in turn, is attached to a heat sink.

Abstract: A highly integrated thermal sensor (10) is responsive to radiation having wavelengths within a predetermined band of wavelengths. The sensor, which may be a thermopile, is comprised of a substrate (16) comprised of at least one semiconductor material. The substrate includes at least one active region disposed within a first surface of the substrate. The sensor further includes a plurality of thermally-responsive junctions (HJ, CJ) between dissimilar materials (22, 24) that are disposed within the at least one active region, wherein at least one of the thermally-responsive junctions is a hot junction. The hot junction is thermally isolated from the substrate by being suspended from the substrate on dielectric bridges or, in another embodiment, by a thermally insulating and patterned polymer. In a backside illuminated embodiment of this invention the sensor further includes an optical cavity (26) formed within a second surface of the substrate in registration with the active region.

Abstract: Transition metals (T) of Group VIII (Co, Rh and Ir) have been prepared as semiconductor alloys with Sb having the general formula TSb.sub.3. The skutterudite-type crystal lattice structure of these semiconductor alloys and their enhanced thermoelectric properties results in semiconductor materials which may be used in the fabrication of thermoelectric elements to substantially improve the efficiency of the resulting thermoelectric device. Semiconductor alloys having the desired skutterudite-type crystal lattice structure may be prepared in accordance with the present invention by using vertical gradient freeze techniques, liquid-solid phase sintering techniques, low temperature powder sintering and/or hot-pressing. Measurements of electrical and thermal transport properties of selected semiconductor materials prepared in accordance with the present invention, demonstrated high Hall mobilities (up to 8000 cm.sup.2.V.sup.-1.s.sup.-1), good Seebeck coefficients (up to 400 .mu.VK.sup.-1 between 300.degree. C.

Abstract: A technique for forming from staring precursors at the molecular level, a sultant thermoelectric material with a reduced thermal conductivity. All staring precursors are dissolved in solution, reduced to remove oxygen, and then combined into a single solution to yield specific stoichiometric ratios. A sol and then a gel is formed, which supercritical solvent extraction is performed upon so as to yield a material having two level porosity and a maximum of a factor of three reduction in thermal conductivity.

Abstract: In a fine structure of a thermoelectric material, fine particles of a material exhibiting Seebeck effect are electrically linked in a loosely contacted state with one another without fusing, having spaces formed at clearances among the fine particles. A method of manufacturing the thermoelectric material comprises a step of compacting fine particles made of a material exhibiting Seebeck effect through a cold pressing. Also, disclosed is a sensor for quantitatively sensing a substance, which comprises a pellet of a powder thermoelectric material, where a temperature difference is generated between two points inside the piece of thermoelectric material. The sensor further includes thermocouples connected to a heater plate (6) and a cooling plate, and a controller which is electrically connected in the loop circuit of the thermocouples for detecting thermoelectric current corresponding to the temperature difference, thereby to control the heating of the heater plate.

Abstract: There are sintered Bi.sub.2 Te.sub.3 -based thermoelectric materials containing Ag.sub.2 S, which prevent p- to n-type transition of Bi.sub.2 Te.sub.3 -based thermoelectric materials during polycrystalline sintering and have improved thermoelectric properties.

Abstract: A superlattice comprising alternating layers of (PbTeSe).sub.m and (BiSb).sub.n (where m and n are the number of PbTeSe and BiSb monolayers per superlattice period, respectively) having engineered electronic structures for improved thermoelectric cooling materials (and other uses) may be grown by molecular beam epitaxial growth. Preferably, for short periods, n+m<50. However, superlattice films with 10,000 or more such small periods may be grown. For example, the superlattice may comprise alternating layers of (PbTe.sub.1-z Se.sub.z).sub.m and (Bi.sub.x Sb.sub.1-x).sub.n. According to a preferred embodiment, the superlattice comprises a plurality of layers comprising m layers of PbTe.sub.0.8 Se.sub.0.2 and n layers of Bi.sub.0.9 Sb.sub.0.1, where m and n are preferably between 2 and 20.

Abstract: A ferroelectric material, its fabrication technique, and use as a detector aterial, in a ferroelectric detector array is disclosed. The material is an alloy of essential pure components of Pb.sub.2 (Fe, Nb)O.sub.2 and Pb.sub.2 (Fe, Ta)O.sub.2 each with respective Curie temperatures. An essentially linear relationship is made for mole fraction compositions versus Curie temperatures of each component in the alloy, between the pure mole fractions and respective Curie temperatures of the pure components. A Curie temperature for the composition of Pb.sub.2 (Fe, [Ta.sub.(1-x), Nb.sub.x ])O.sub.6 is determined, where x is the mole fraction of Pb.sub.2 (Fe,Nb)O.sub.2 and 1-x is the mole fraction of Pb.sub.2 (Fe, Ta)O.sub.2, with x having a value greater than zero and less than one.

Abstract: An intermetallic film thermocouple has an amorphous phase and a Seebeck coefficient above 900 .mu.V/.degree. C. Such thermocouples can be prepared by vapor-depositing an intermetallic and quenching the resulting intermetallic film.

Abstract: The disclosure is directed to a method for converting between heat energy and electric energy which is characterized in that a carbon intercalation compound is employed as a thermoelectric material by utilizing a temperature difference in a direction perpendicular to the structure of carbon layers, or a method for producing a light-heat converting material which is characterized in that a thin metallic layer like a translucent mirror is caused to adhere to the inner surface of a light transmissive hollow tube by pyrolytically decomposing at a temperature approximately below 1000.degree. C., with hydrocarbons being introduced into the hollow tube at the rate of a predetermined amount per hour.

Abstract: In a thermoelectric refrigeration material with thermoelectric conversion characteristic, in order to improve crystallinity of a system of bismuth-antimony (Bi-Sb) and thereby to improve the figure of merit Z, bismuth (Bi), antimony (Sb) and silicon monoxide (SiO) are deposited on a substrate at a predetermined rate in a thermally nonequilibrium state by an ICB method so that a thin film crystal having a granular structure including crystal grains of around one micron is obtained. Consequently, the figure of merit Z can be improved by selectively varying the thermal conductivity K which largely depends upon the crystallinity and which is one of elements of the figure of merit Z determining the thermal conversion coefficiency.

Abstract: A thermoelectric material can be obtained by co-pulverizing and mixing a material containing at least bismuth and a material containing at least tellurium, without being alloyed by melting, and then molding and sintering. This thermoelectric material has high performance and can be utilized in a variety of fields such as thermoelectric power generation and thermoelectric cooling, a temperature sensor, space development, marine development, and electric power generation in the remote areas. Since metal elements are used as a starting material, the starting material can be easily prepared. Moreover, in the production steps, the thermoelectric material can be produced in a high yield at a low energy consumption level by a simplified manner, without a complicated operation or special apparatus, and its production cost can be decreased.