Thermal conductivity of thermoelectric thick films deposited by an electrodeposition process

Abstract

Due to the lack of advanced technology and difficulties in sample preparing, direct measurement of thermal conductivity for thin-film thermoelectric material is rarely reported in literatures. In this work, there are four types of thermoelectric thin films measured for their intrinsic thermal conductivity by using a modified parallel-strip technique. These four types of thermoelectric thin films are of Bi-Te and Sb-Te compositions, resulting from electrodeposition process with different aqueous solutions. From the measurement results, three types of the films shown quite low intrinsic thermal conductivity less than 0.5 Wm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> K <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> ; and one type of the films can not be measured due to sample preparing problem. According to the scanning electron microscope observations, the grain boundaries in the thermoelectric thin films are probably the cause that results in their low thermal conductivity and the fragile structure is the cause of difficulty for the sample preparation.