摘要
This study investigates the potential of polycrystalline MoS
as a diffusion barrier for Ru interconnects using in situ transmission electron microscopy (TEM) to assess its performance. By examining TEM diffraction and imaging, we evaluate the effectiveness of MoS
in suppressing interdiffusion, particularly focusing on the interactions and phase transformations between Ru and Si. When subjected to elevated temperatures, MoS
gradually loses its ability to block the interdiffusion, allowing Si to diffuse through the MoS
layer and form Ru
Si
within the Ru layer. Notably, plasma-treated polycrystalline MoS
(defective MoS
) exhibits a slightly lower diffusion-blocking temperature of 700 °C, likely due to dangling bonds that improve interfacial adhesion. To complement our experimental observations, we performed density functional theory (DFT) calculations to compare Si diffusion in pristine and defective MoS
. Additionally, we assessed the electrical properties of Ru interconnects by measuring the resistivity and adhesion strength. These results underscore the considerable potential of polycrystalline MoS
even with defects as an effective diffusion barrier for Ru interconnects in semiconductor devices.