The long-term stability of electrical resistance and magnetoresistance in nanostructured La 1-x Sr x MnO 3 (x = 0.17) manganite thin films grown on lucalox (Al 2 O 3 + MgO) substrate by the MOCVD method was investigated. It was found that the storage of up to 3 months of the free surfaces of these films in normal atmosphere (air) conditions increases their resistivity by almost two times, while the annealing of the films in an Ar atmosphere at 450 °C decreases their resistivity only by 15%. It was concluded that the final increase of resistivity is determined by a long-term relaxation of the grain boundaries in the nanostructured films. The magnetoresistance of the films does not change significantly, which produces an advantage for magnetic field sensor applications. The passive protective coating of the free surfaces of the films stabilizes their electrical and magnetic properties. The results were analysed using various electron scattering mechanisms when the films were in a ferromagnetic state, and the Mott's variable range hopping model when they were in a paramagnetic insulating state.

In this work atomic layer deposited Tm 2 O 3 has been investigated as a high-k dielectric for Ge-based gate stacks. It is shown that when Tm 2 O 3 is deposited on high-quality Ge/GeO 2 gates, the interface state density of the gate stack is degraded. A series of post-deposition anneals are studied in order to improve the interface state density of Ge/GeO x /Tm 2 O 3 gates, and it is demonstrated that a rapid thermal anneal in O 2 ambient can effectively reduce the interface state density to below 5·10 11 cm -2 eV -1 without increasing the equivalent oxide thickness. Fixed charge density in Ge/GeO x /Tm 2 O 3 gates has also been investigated, and it is shown that while O 2 post-deposition anneal improves the interface state density, the fixed charge density is degraded.

This work demonstrates high quality Ge/GeO2 interfaces fabricated by O2 RTA that are degraded by a good quality SiO2 layer deposited by ALD. However, neither O3 and H2O precursors commonly used during subsequent high-k ALDs nor Si precursor AP-LTO-330 do not degrade the interface. Thus Dit increase after SiO2 deposition is likely due to intermixing. Therefore, the effect of subsequent ALDs on the interface quality has to be considered while designing Ge-based gate stacks.

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