INVESTIGATION OF THERMOMETRIC MATERIAL Ti1-xScxCoSb. KINETIC, ENERGY AND MAGNETIC CHARACTERISTICS

2019;
: pp. 16-22
1
Lviv Polytechnic National University
2
Lviv Polytechnic National University
3
Lviv Polytechnic National University
4
Ivan Franko National University of Lviv
5
Ivan Franko National University of Lviv
6
Ivan Franko National University of Lviv

The first part of the complex study of the thermometric material Ti1-xScxCoSb for the production of sensitive elements of thermoelectric and resistive thermotransducers is presented. The kinetic, energetic and magnetic characteristics of the Ti1-xScxCoSb semiconductor thermometric material in the ranges T=80–400 K, x=0.005–0.15 have been investigated. The mechanisms of simultaneous generation of structural defects of acceptor and donor natures in the semiconductor are revealed. Previous studies have found that the results of modeling the temperature and kinetic characteristics of thermometric materials based on TiCoSb do not agree with the results of experimental measurements, which does not allow predict and obtain a material with predetermined characteristics. It has been suggested that the structure of the TiCoSb, as the basic semiconductor, is defective and contains vacancies in the position 4a of the atoms, which itself generates acceptors. In addition, the occupation of impurity atoms of other positions, which also generates acceptors, is not excluded. For example, while introducing into the structure of a TiCoSb compound atoms V by substitution at the 4a position of the donor-generating Ti-atoms, simultaneous partial occupation by the V atoms of the crystallographic 4c position of the Co atoms may occur. The latter leads to the generation of acceptor nature structural defects.

The importance of understanding the structural and energetic features of the TiCoSb basic semiconductor is crucial since it provides a way of optimizing the performance of thermometric materials by doping with a certain type and concentration of impurities. The result of a comprehensive study of the kinetic, energy and magnetic characteristics of Ti1-xScxCoSb is the detection of donor and acceptor structural defects in a semiconductor. It is suggested that the thermometric material Ti1-xScxCoSb observed discrepancies is caused by the incomplete understanding of the spatial arrangement of impurities and their energy levels generated in the TiCoSb basis. This problem requires additional research, which will be considered sooner.

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