The effect of Mo crystallinity on diffusion through the Si-on-Mo interface in EUV multilayer systems

摘要

Thermally induced diffusion through the Si-on-Mo interface of multilayers with either amorphous or polycrystalline Mo layers has been investigated using grazing incidence and wide angle x-ray reflectometry. Diffusion through the Mo-on-Si interface was reduced by applying a diffusion barrier, allowing us to probe the diffusion at the opposite, Si-on-Mo interface. We found that diffusion through this interface is much slower for polycrystalline Mo than for amorphous Mo layers. The reason for this difference might be the larger defect concentration in amorphous Mo as compared to crystalline Mo.