A South Korean research team has developed a new process technology that can stably produce thermoelectric semiconductors at a low cost.
The research team at the electronic material research department of the Korea Institute of Science and Technology (KIST) led by Doctor Kim Jin-sang and Baik Seung-hyup announced on March 29 that it has developed a productive technology to manufacture thermoelectric semiconductors with a mechanical doping and pressing method which is different from existing methods.
A thermoelectric semiconductor is an element that directly converts the heat around it into electric power or directly cools down the material with electricity. It is widely used in water purifiers that provide both hot and cold water and small-sized refrigerators. An electronic concentration is an important factor in thermoelectric semiconductors because it determines the cooling and generating capacity of materials. In general, the doping technology adding impurities have been used in the electronic concentration of thermoelectric semiconductors.
However, the research team applied the mechanic doping technology that controls the electronic concentration by mechanically modifying materials after melting it, instead of the existing impurities doping process technology. In addition, it maximized thermoelectric efficiency by bringing crystal grains in thermoelectric semiconductors in line in one direction through the pressing process method. The thermoelectric material producing method has high competitiveness in terms of price, performance and durability, according to the research team.
KIST Doctor Baik Seung-hyup said, “When applying the mechanic doping concept to thermoelectric semiconductors, it is possible to achieve customized doping that shows optimal thermoelectric power regardless of the purity of raw materials. The new technology will also be applied to the process that controls physical properties of various semiconductor materials which have a similar crystalline structure and stably produces them.”
The findings from the study were published in the online edition of Acta Materialia.