Diffusion annealing of Mo/MoSi2 couple and silicon diffusivity in Mo5Si3 layer

Kinetics of molybdenum disilicide (MoSi2) layer transformation into Mo5Si3 one was studied at isothermal annealing of the MoSi2/Mo diffusion couple within the temperature interval 1200–1800 °C. It was revealed that the growth of intermediate silicide layer followed a parabolic law and did not accompanied by formation of the lowest Mo3Si silicide. By analyzing the diffusion problem solid-phase diffusion coefficient of silicon in the Mo5Si3 layer was calculated.