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Thermoelectric devices for energy conversion and temperature control have been widely exploited in various industrial fields, and it is possible to extend the number of applications by miniaturizing. A typical application for the energy conversion is a wristwatch, which incorporates a micro-thermoelectric generator. The thermoelectric devices for temperature control are mainly utilized for laser diodes in order to keep their emission wavelength constant; also they are used for small scale power generators, detectors, low weight refrigerators etc. Their salient features include low weight, extremely high reliability over extended periods of operating time, no moving parts, silent operation etc. To further minimize the thermoelectric device size, various industrial applications might be produced, for instance, spot-cooling of electronic devices. There are presently many deposition methods to obtain thermoelectric thin films with high quality, but it is challenging to reduce their fabrication cost and the waste produced in a normal etch-based process. Printing processes such as screen and inkjet printing are attractive techniques to reduce the fabrication cost. If they can be applied to thermoelectric devices, micro-generators and micro-Peltier coolers for micro-electronic devices might be available with low-cost fabrication.

Bismuth telluride (Bi2Te3) and its alloys are known as one of the best thermoelectric materials currently available near room temperature (200-600K). These materials have been extensively investigated in bulk crystalline form because of their excellent thermoelectric properties, whereas in thin film form so far relatively very little attention has been paid. The electrodeposition appears to be a promising and low-cost growth method for obtaining films of high quality because offers the advantages of low synthesis temperature, large area deposition, high growth rates and high throughput. Moreover, the electrolyses can be made in laboratory atmosphere as compared to standard physical and chemical vapor deposition techniques.

                In the present Project the Romanian side proposes the study of n-BiTeSe and p-BiSbTe thermoelectric thin films preparation by electrodeposition technique, only. Experimentally, the influences of preparation on film structure, composition and performances will be investigated. For studying the electrodeposition mechanism and layers characterization several electrochemical methods (potentiodynamic curves, cyclic voltammetry, electrochemical impedance spectroscopy, chronoamperometry), SEM microscopy, EDX, AFM and X ray diffraction will be used. The results will be compared with Chinese partner. An optimized mini-thermoelectric module will be proposed, by simulation of heat and electricity transmittance through the module. Together with the Chinese partner, for the manufacturing of mini thermoelectric generator based on the proposed module will be use either electrodeposition (both Romania and China) or photolithography (China) technologies. Investigations on interaction of different thermoelectric layers from generator structure will also be made. The elucidation of the correlation between fabrication techniques and mini thermoelectric generator performances will be performed.