Microstructure and phonon behavior in W/Si periodic multilayer structures

The crystallinity of the tungsten (W) phase was improved with an increase in the thickness of this layer in the periodic W/Si multilayer structure. Both the alpha- and beta-W phases were grown simultaneously and the contribution of these phases was modified by a change in the thickness of the W layers. For thinner W layers, the thermodynamically metastable beta-W phase dominated, and with an increase in thickness, this phase was suppressed and the stable alpha-W phase became prominent. The crystallite size of these phases was almost linearly proportional to the thickness of the W layers in the multilayers. With the increase in thickness of Si layers in multilayers, Raman scattering showed a decrease in the bond-angle deviation of Si-Si bonding in the amorphous Si phase. The study revealed ordering of Si-Si bonding in the amorphous phase of Si with an increase in thickness of these layers in periodic W/Si multilayers.

Automated summary

The crystallinity of the tungsten phase in the multilayer structure was improved with an increase in the thickness of this layer. Both alpha- and beta-W phases were grown simultaneously, and their contribution was modified by the thickness of the W layers. The size of the crystallites in these phases was linearly proportional to the thickness of the W layers. Raman scattering showed a decrease in the deviation of Si-Si bonding with an increase in the thickness of the Si layers, indicating an ordering phenomenon.