Effect of Pulsed Photon Treatment on the Mechanical Properties of Semiconductor Thermoelectric Legs, Based on Bi2Te3–Bi2Se3 Solid Solutions, and the Adhesion of Switching Layers

Abstract

We carry out comparative studies of the phase composition, morphology, and hardness of semiconductor legs based on the n-type solid solution Bi₂Te₃−Bi₂Se₃, obtained by hot pressing, after surface modification (mechanical processing and pulsed photon treatment (PPT) with incoherent light). Using shear tests, we determine the adhesion of switching and barrier Mo–Ni layers on the modified surfaces of semiconductor legs. Pulsed photon treatment stimulates local recrystallization of the imperfect layer near the surface of samples of the Bi₂Te₃−Bi₂Se₃ solid solution to a depth of 100−200 nm, which increases the hardness of the surface layers. It is shown that the mechanical polishing and subsequent pulsed photon treatment of thermoelectric legs increases the adhesion of the switching and barrier Mo–Ni layers by 3–4 times, which can contribute to the efficient and stable operation of a thermoelectric generator battery.