Thermoelectric thick film was fabricated by screen printing process with using p-type Bi-Te-Sb powders. The powder was synthesized by melting, milling and sintering process and hydrogen reduced to enhance the thermoelectric property. The thick film of Bi-Te-Sb powder was fabricated by screen printing method and baked at the optimized conditions. The thermal conductivity, the electrical resistivity and Seeback coefficient of thick film were measured and the thermoelectric performance was analyzed in terms of film characteristics and its microstructure. Finally, the feasibility of thermoelectric thick film into micro cooling device on CPU chip was discussed in this study.

From a viewpoint of heat stress at high temperatures and contact thermal resistance, it is confirmed that the optimal structure is the skeleton structure using Cu substrate on the cooling side, which has excellent heat conductivity and the optimal installation method is to adopt a carbon sheet and a mica sheet to the high temperature side, where Si grease is applied to the low temperature side, under pressurized condition. The power of the developed modules indicated 0.5W in an module and 3.8 W with a SiGe module at 823K, respectively.

New PM route via bulk mechanical alloying is developed to fabricate the solid solution semi-conductive materials with and for 0 < x, y < 1 and to investigate their thermoelectric materials. Since is n-type and both and are p-type, pn-transition takes place at the specified range of germanium content, x, and tin content, y. Through optimization of chemical composition, solid-solution type thermoelectric semi-conductive materials are designed both for n-and p-type materials.

The p-type semiconductor thermoelectric materials were fabricated by melting, milling and sintering process and their thermoelectric properties were characterized. The compound materials were ball-milled with milling time and the powders were sintered by spark plasma sintering process. The ball milled powders had equiaxial shape and approedmately in size. The figure of meritz of sintered thermoelectric materials decreased with milling time because of lowered electrical resistivity. The thermoelectric properties of materials have been discussed in terms of electrical property with ball mill process.

Fe-doped skutterudite with a nominal composition of has been synthesized by mechanical alloying (MA) of elemental powders, followed by hot pressing. Phase transformations during mechanical alloying and hot pressing were systematically investigated using XRD. Single phase skutterudite was successfully produced by vacuum hot pressing using as-milled powders without subsequent annealing. However, second phase in the form of marcasite structure was found to exist in case of , suggesting the solubility limit of Fe with Co in this system. Thermoelectric properties as functions of temperature and Fe contents were evaluated for the hot pressed specimens. Fe substitution up to x=1.5 with Co in appeared to increase thermoelectric figure of merit (ZT) and the maximum ZT was found to be 0.78 at 525K in this study.

Abstract Direct solid state synthesis by hot pressing has been applied in order to produce high efficiency bulk specimens. Single phase with 98.5% of theoretical density was successfully produced by direct hot pressing of elemental powders containing 1.2 at.% excess Zn. Thermoelectric properties as a function of temperature were investigated from room temperature to 600 K and compared with results of other studies. Transport properties at room temperature were also evaluated. Thermoelectric properties of single phase materials produced by direct synthesis were measured and are comparable to the published data. Direct solid state synthesis by hot pressing provides a promising processing route in this material