Diffusion processes in contact areas thermoelements based on Pb-Sb alloys
Abstract
In this work, the diffusion processes on the contact regions of the metal-solder-semiconductor system are experimentally investigated. The diffusion coefficients, activation energies and preexponential factors have been determined in samples switched with solders based on Bi-Sb and Pb-Sb. It has been found that lead-based solder is significantly more inert to thermoelectric materials. The study of the interaction of Pb-Sb and Bi-Sb solders with semiconductor materials of the branches of n- and p-type cooling thermoelements and the metal of the current-carrying bus bar was carried out after isothermal annealing at different temperatures. The samples were annealed in a vacuum of (10−3 Torr.) at temperatures of 100, 150, 180, 220°C for 150 hours. Diffusion coefficients at each temperature were estimated by the formula D=x2/2t. The experimental results of the average thickness of the diffusion phases and the value of the diffusion coefficient at different temperatures are presented.