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Information × Registration Number 0206U002678, 0103U001537 , R & D reports Title The study of interdiffusuin and chemical reactions in multilayer film compositions under annealing and irradiation popup.stage_title Head Kondratenko Valeriy, Registration Date 17-02-2006 Organization The Kharkov state polytechnical university popup.description2 Growth behaviours for Mo/Si multilayer film compositions (MFC) under substrate bias (SB) (-300 V) are studied. Molybdenum crystal surface is an origin of interface roughness, in absence of the SB that facilitates to developing roughness from the substarte to the MFC surface. Bias potential applied during Si deposition smoothes the roughness and improves the layered morphology. Significant widening of amorphous mixed zones (AMZ) at the Si-on-Mo interfaces is observed when high bias potential (-300 V) is applied. Growth of bias during Mo deposition brings to the roughness development at Mo-on-Si interfaces and to the gtowth of AMZ thickness. Processes of ion-beam intermixing in Mo/Si MFCs with 40-keV He+ ions and doses up to 4x10^16 cm-2 are studied. Intemixing degree was found to depend linearly on irradiation dose with ballistic intermixing mechanism being realized. Intervals of weak and strong dependence of intermixing on temperature are revealed. Activation energies for these intervals are determined. The role of carbon barrier layers in suppression of Mo-Si intermixing during both thermal and ion-beam influence are studied. Specific structural changes in Sc/Si multilayer mirrors irradiated with extreme ultraviolet laser pulses (l = 46.9 nm) at near-damage threshold fluences (0.06-0.23 J/cm2) are studied by methods of SEM, TEM, electron diffraction, and small-angle x-ray diffractometry (l=0.154 nm). We have identified melting of subsurface layers as the principal degradation mechanism for the mirrors. Diffusion intermixing of layers modifies layered structure in heat-affected zone. The heat-affected zone thickness is found to be 0.05-0.10 mm or 2-4 periods. The damage threshold of the mirrors is typically ~ 0.08 J/cm2. It is shown that both heat liberation during silicide formation and low heat conduction of layered system significantly decreases the degradation threshold of Sc/Si multilayer mirrors. Product Description popup.authors popup.nrat_date 2020-04-02 Close