Structural and Magnetoresistive Properties of Nanometric Films Based on Iron and Chromium Oxides on the Si Substrate

Ultraviolet photons of KrF laser (248 nm) was used for the synthesis of nanometric films based on iron and chromium oxides (Fe₂O_3 - X (0 ≤ x ≤ 1) and Cr_3 - X O_3 - Y (0 ≤ x ≤ 2; 0 ≤ y ≤ 2)) with variable thickness, stoichiometry, and electrical properties. Film deposition was carried out on the silicon substrate Si < 100 > at the substrate's temperature T _S = 293 K. X-ray diffraction and X-ray reflectometry analysis were used for the obtained structure characterization. Such a combined investigation reveals the composition and texture for samples investigated and provides useful information about layer thickness and roughness. Fe₂O_3 - X (0 ≤ x ≤ 1) nanometric films demonstrate the negative magnetoresistance in magnetic fields up 7 kOe. At the same time, for hybrid systems of the alternate layers Fe₂O_3 - X (0 ≤ x ≤ 1)/Cr_3 - X O_3 - Y (0 ≤ x ≤ 2; 0 ≤ y ≤ 2), the positive magnetoresistance as well as the magnetic hysteresis and magnetoresistivity switching effect in the low magnetic fields were observed.