SYNTHESIS FEATURES AND RADIATION PROTECTION EFFICIENCY OF MULTILAYER STRUCTURES BASED ON Ni-Fe ELECTRODEPOSED FILMS

Modern semiconductor devices and microchips are sensitive to the effects of ionizing radiation. Nevertheless, they are widely used in military and space technology, in the nuclear industry. At the same time, a number of technological, circuit and software solutions are used to reduce the effects of radiation exposure. The most preferable method is one based on using shields, due to its low cost and excellent radiation properties of shield’s materials. Recently, special attention has been paid to the study of multilayer structures. Experimental samples of Ni-Fe alloys and multilayer Ni-Fe/Cu structures with different chemical composition were obtained by electrochemical deposition. The dependence of chemical composition variation from deposition conditions was determined. Ni-Fe alloys crystal structure was studied using X-ray diffraction. Shielding properties of Ni-Fe/Cu multilayer structures were investigating on linear accelerator ELA-4 under 4 MeV electron irradiation. Silicon p-MOSFETs were used as test structures. Evaluation of electron flow weakening effectiveness was performed by current-voltage characteristics changing – threshold voltage of pMOS-transistors, which were located behind shields based on NiFe/Cu multilayered structures and without shields. It was found that increasing number of Ni-Fe layers within the same total thickness leads to maximum shielding efficiency.

electrodeposition, shielding, shields, radiation protection, Ni-Fe alloys

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