Interlayer transition zones in Mo/Si superlattices

Abstract

The formation of interlayer transition zones (ITZs) in sputtered Mo/Si multilayer structures was studied by means of cross-section electron microscopy and grazing incidence reflectivity measurements. For the evaluation and calculation of interface effects the multiperiodic design of Mo/Si structure was used. It was found that the thickness asymmetry of ITZs (Mo-on-Si and Si-on-Mo) in Mo/Si multilayer structures depends on the degree of perfection of the crystalline structure of the molybdenum layer. A transition from asymmetrical to symmetrical ITZs with a disordering of the molybdenum crystalline structure was shown. A model for the formation mechanism of asymmetrical ITZs at the different interfaces in Mo/Si multilayer structures is suggested. According to this model, ITZ formation at the Mo-on-Si interface is controlled by the surface diffusion of Si atoms on the growing molybdenum surface. In contrast, ITZ formation at the Si-on-Mo interface is determined by the bulk diffusion of Si atoms in textured molybdenum grain

In vacuo growth studies of Ru thin films on Si, SiN, and SiO2 by high-sensitivity low energy ion scattering

“…As a result, Ru could intermix more on top of Si than Si on top of Ru. This phenomenon has already been observed by Yulin et al 52 in the growth of Mo/Si multilayers where there was a larger intermixing in the Mo-Si interface compared to the Si-Mo interface, associated to the crystallinity of the Mo layers. This interfacial asymmetry was no longer present when the Mo layers were amorphous.…”

Optical Response Near the Soft X-Ray Absorption Edges and Structural Studies of Low Optical Contrast System Using Soft X-Ray Resonant Reflectivity

“…This result agrees well with the composition obtained using nondestructive soft X-ray resonant reflectivity. Our results of MoSi 2 composition at interfaces of Mo/Si ML system agrees well with previously reported results using transmission electron microscopy [107].…”

“…Although the principle is applicable in general to any multilayer system near the resonant absorption edges, here we demonstrate the technique through characterization of Mo/Si multilayer (ML) system [106,107] using simulation and experiment. Before moving to SXRR, we show the difficulty in probing such low contrast interlayer composition using conventional hard XRR method.…”

Asymmetric silver to oxide adhesion in multilayers deposited on glass by sputtering

“…The resulting structure of the interface and therefore the adhesion energies will then be different. A similar case of asymmetric interfaces appear in the Mo/Si multilayers developped for EUV reflective optics [21].…”