Effect of Thermomigration on Electromigration in SWEAT Structures

This paper investigates thermomigration (TM) and electromigration (EM) in SWEAT structure. Firstly, the distribution of temperature along SWEAT structure during EM is obtained by using finite element (FE) simulation. The FE simulation results show that the temperature is almost uniformly distributed in the most region of narrow line in SWEAT structure, but temperature decreases rapidly at both sides of conductor. Accordingly, the temperature gradient in the narrow line of SWEAT structures is calculated. Then, we apply the obtained temperature and temperature gradient in the governing equation of EM in terms of atomic concentration. The numerical results show that the TM caused by temperature gradient causes the material depletion near both ends of conductor. At the same time, atoms diffuse from the middle region of conductor to both sides driven by the atomic concentration, causing the voids in middle of conductor.