A thermoelectric conversion material includes a base material that is a semiconductor having Si and Ge as constituent elements, a first additive element that is different from the constituent elements, has a vacant orbital in a d or f orbital located inside an outermost shell thereof, and forms a first additional level in a forbidden band of the base material, and oxygen. The oxygen content ratio is 6 at % or less.

A magnesium-based thermoelectric conversion material includes a first layer formed of Mg.sub.2Si and a second layer formed of Mg.sub.2Si.sub.xSn.sub.1-x (here, x is equal to or greater than 0 and less than 1), in which the first layer and the second layer are directly joined to each other, and within a junction surface with the first layer and in the vicinity of the junction surface, the second layer has a tin concentration transition region in which a tin concentration increases as a distance from the junction surface increases. The junction layer is regarded as a site in which a tin concentration is found to be equal to or lower than a detection limit by the measurement performed using EDX.

A structure and method for cooling a three-dimensional integrated circuit (3DIC) are provided. A cooling element is configured for thermal connection to the 3DIC. The cooling element includes a plurality of individually controllable cooling modules disposed at a first plurality of locations relative to the 3DIC. Each of the cooling modules includes a cold pole and a heat sink. The cold pole is configured to absorb heat from the 3DIC. The heat sink is configured to dissipate the heat absorbed by the cold pole and is coupled to the cold pole via an N-type semiconductor element and via a P-type semiconductor element. A temperature sensing element includes a plurality of thermal monitoring elements disposed at a second plurality of locations relative to the 3DIC for measuring temperatures at the second plurality of locations. The measured temperatures control the plurality of cooling modules.

A thermoelectric conversion element includes a thermoelectric conversion material portion having a compound semiconductor composed of first base material element A and second base material element B and represented by A.sub.x-cB.sub.y with value of x being smaller by c with respect to a compound A.sub.xB.sub.y according to a stoichiometric ratio, a first electrode disposed in contact with the thermoelectric conversion material portion, and a second electrode disposed in contact with the thermoelectric conversion material portion and apart from the first electrode. An A-B phase diagram includes a first region corresponding to low temperature phase, second region corresponding to high temperature phase, and third region corresponding to coexisting phase, sandwiched between the low temperature phase and the high temperature phase, in which the low and high temperature phases coexist. A temperature at a boundary between the first region and the third region changes monotonically with a change in c.

A thermoelectric element to convert thermal energy into electrical energy includes a first electrode part, a second electrode part having a different work function than the first electrode part and arranged at a distance from the first electrode part, on a same surface of a substrate as the first electrode part, and a middle part provided between the first electrode part and the second electrode part.

The present invention provides: a thermoelectric conversion material capable of being produced in a simplified manner and at a lower cost and excellent in thermoelectric performance and flexibility, and a method for producing the material. The thermoelectric conversion material has, on a support, a thin film of a thermoelectric semiconductor composition containing thermoelectric semiconductor fine particles, a heat-resistant resin and an inorganic ionic compound. The method for producing a thermoelectric conversion material having, on a support, a thin film of a thermoelectric semiconductor composition containing thermoelectric semiconductor fine particles, a heat-resistant resin and an inorganic ionic compound includes a step of applying a thermoelectric semiconductor composition containing thermoelectric semiconductor fine particles, a heat-resistant resin and an inorganic ionic compound onto a support and drying it to form a thin film thereon, and a step of annealing the thin film.

A thermoelectric material includes a parent phase in which an MgSiSn alloy is a main component, a void formed in the parent phase, and a silicon layer that is formed on at least a wall surface of the void and that includes silicon as a main component. The thermoelectric material further includes MgO in an amount of 1.0 wt. % or more and 20.0 wt. % or less. The silicon layer includes amorphous Si, or amorphous Si and nanosized Si crystals, and the parent phase includes a region in which the composition ratio of the Si of the chemical composition of the MgSiSn alloy is higher than in the other regions and a region in which the composition ratio of the Sn of the chemical composition of the MgSiSn alloy is higher than in the other regions. With these configurations, the thermoelectric material realizes both lower thermal conductivity and lower electrical resistivity.

There is provided a thermoelectric conversion material in which a first layer containing Mg.sub.2Si.sub.xSn.sub.1-x (here, 0<x<1) is directly joined to a second layer containing Mg.sub.2Si.sub.ySn.sub.1-y (here, 0<y<1), where x/y is set within a range of more than 1.0 and less than 2.0. There is also provided a thermoelectric conversion element including the thermoelectric conversion material and electrodes each joined to one surface and the other surface of the thermoelectric conversion material. There is also provided a thermoelectric conversion module including terminals each joined to the electrodes of the thermoelectric conversion element.

A semiconductor sintered body comprising a polycrystalline body, wherein the polycrystalline body includes silicon or a silicon alloy, wherein the average grain size of the crystal grains forming the polycrystalline body is 1 μm or less, and wherein nanoparticles including one or more of a carbide of silicon, a nitride of silicon, and an oxide of silicon are present at a grain boundary of the grains.

An alloy is provided that consists essentially of
(Ti.sub.xTa.sub.yV.sub.zA.sub.cNb.sub.1-x-y-z-c)(Fe.sub.1-dMn.sub.d).sub.a(Sb.sub.1-eSn.sub.e).sub.b,
wherein 0.06≤x≤0.24, 0.01≤y≤0.06, 0/08≤z≤0.4, 0.9≤(a, b)≤1.1, 0≤c≤0.05, 0≤d≤0.05 and 0≤e≤0.1 and A is one or more of the elements in the group consisting of Zr, Hf, Sc, Y, La, and up to 5 atom % impurities.