A catheter has a cooling distal section for freezing tissue to sub-zero temperatures with one or more miniature reverse thermoelectric or Peltier elements, also referred to herein as micro-Peltier cooling (MPC) units or electrodes. The MPC units may be on outer surface of an inflatable or balloon member or a tip electrode shell wall that has a fluid-containing interior cavity acting as a heat sink. Each MPC unit has a hot junction and a cold junction whose temperatures are regulated by the heat sink, and a voltage/current applied to the MPC units. A temperature differential of about 70 degrees Celsius may be achieved between the hot and cold junctions for extreme cooling, especially where the MPC units include semiconductor materials with high Peltier co-efficients. An outer coating of thermally-conductive but electrically-insulative material seals the MPC units to prevent unintended current paths through the MPC units.

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 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.

A thermoelectric device includes active elements containing thermoelectric materials of silicon, an alloy of silicon, a metal-silicide or silicon composite and an interconnection zone consisting of a metal interconnect and a re-crystallized phase consisting of material from the active thermoelectric elements. The metal interconnect is from a metal that does not form metal silicides in a solid state, has a certain solubility for components of the thermoelectric elements in the liquid phase and a low solubility of these components in the solid phase. The active thermoelectric elements are shaped with a first and a second contact interface. The interconnection between the different thermoelectric elements consists of at least two phases of material, one of which is mainly the metallic interconnection material, the other is formed by the re-crystallized components of the thermoelectric materials.

The present disclosure relates to an energy harvesting system for generating electrical energy by using a solar cell and a thermoelectric device. The energy harvesting system according to one embodiment of the present disclosure may include a solar cell for generating electrical energy based on sunlight; an interface layer located under the solar cell and including a heat transfer layer for transferring heat generated by the solar cell; a thermoelectric device located under the interface layer, including a first electrode, a second electrode, and a thermoelectric channel located between the first and second electrodes, and configured to generate electrical energy based on a temperature difference between the first and second electrodes that occurs when heat generated by the solar cell is transferred to the first electrode through the heat transfer layer; and a cooling layer located under the thermoelectric device and cooling the second electrode to increase the temperature difference.

A method includes forming a plurality of first semiconductor mesa structures at a first semiconductor substrate. The first semiconductor substrate has a first conductivity type. The method further includes forming a plurality of second semiconductor mesa structures at a second semiconductor substrate. The second semiconductor substrate has a second conductivity type. The method further includes providing a glass substrate between the first semiconductor substrate and the second semiconductor substrate. The method includes connecting the first semiconductor substrate to the second semiconductor substrate so that at least a portion of the glass substrate is located laterally between the first semiconductor mesa structures of the plurality of first semiconductor mesa structures and the second semiconductor mesa structures of the plurality of second semiconductor mesa structures.

A semiconductor sintered body comprising a polycrystalline body, wherein the polycrystalline body comprises silicon or a silicon alloy, and the average grain size of the crystal grains constituting the polycrystalline body is 1 μm or less, and the electrical conductivity is 10,000 S/m or higher.

A thermoelectric conversion device including an n-type thermoelectric converter, a p-type thermoelectric converter, a high temperature-side electrode with which one end of the n-type thermoelectric converter and one end of the p-type thermoelectric converter are put into contact, a first low temperature-side electrode in contact with another end of the n-type thermoelectric converter, and a second low temperature-side electrode in contact with another end of the p-type thermoelectric converter, wherein in the n-type thermoelectric converter, the side in contact with the high temperature-side electrode is composed of a carrier generation semiconductor containing Mg.sub.2Sn, and in the n-type thermoelectric converter, the side in contact with the first low temperature-side electrode is composed of a carrier transfer semiconductor containing Mg.sub.2Si.sub.1-xSn.sub.x, wherein 0.6≦x≦0.7, and a first n-type dopant.

Flexible thermoelectric generators and methods of manufacturing are disclosed. In one embodiment, a flexible thermoelectric generator includes a plurality of pillars, a first and a second plurality of flexible interconnects, and a flexible material. The plurality of pillars having a first side and a second side. The first plurality of flexible interconnects electrically connecting pairs of the plurality of pillars on the first side. The second plurality of flexible interconnects electrically connecting the pairs of plurality of pillars on the second side. The first and the second plurality of flexible interconnects alternate among the pairs of plurality of pillars to form an electrical circuit having a first end and a second end. The flexible material covering the first and second plurality of flexible interconnects and having an external surface. The flexible material is configured to conduct thermal energy from the external surface to the plurality of pillars.

A thermoelectric converter is provided where an n-type boron carbide element is paired with a p-type boron carbide element and placed between a eat sink and a high temperature are, such as the ocean in which a submarine operates, and the interior of that submarine, respectively. Boron carbide elements suitable for use in this invention are deposited from meta carborane (n-type) together with dopants to emphasize n-type character, such as chromocene, and orthocarborane, together with dopants to emphasize p-type character, such as 1,4 diaminobenzene to form the p-type element.