The paper presents results for zinc oxide films grown at low temperature regime by Atomic Layer Deposition (ALD). We discuss electrical properties of such films and show that low temperature deposition results in oxygen-rich ZnO layers in which free carrier concentration is very low. For optimized ALD process it can reach the level of 10 15 cm -3 , while mobility of electrons is between 20 and 50 cm 2 /V·s. Electrical parameters of ZnO films deposited by ALD at low temperature regime are appropriate for constructing of the ZnO-based p-n and Schottky junctions. We demonstrate that such junctions are characterized by the rectification ratio high enough to fulfill requirements of 3D memories and are deposited at temperature 100 o C which makes them appropriate for deposition on organic substrates.

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This article reports on a comprehensive experimental study of 16O+ and 90Zr+ ion co-implanted SrTiO3 (STO) single crystals. In this study, STO was used as a model material to simulate a waste form for disposal of radioactive 90Sr that decays to 90Y and subsequently to 90Zr by emission of β– particles. Sequential 16O+ and 90Zr+ ion implantation at 550 K was performed and Zr and O atomic concentrations of up to 1.5 atom % each in STO were achieved. A number of analytical methods were employed to characterize the implanted STO, including secondary-ion mass spectroscopy, multiaxial ion-channeling analysis, and high-resolution X-ray diffraction. The results show that a high defect concentration was generated and accumulated in STO during the ion implantation, but the crystal structure was not rendered fully amorphous. Thermal annealing at 1273 K leads to a significant defect recovery at the surface with little recovery occurring at the damage peak, where a modest recovery occurs upon further annealing at 1423 K. Some of the implanted Zr species are well aligned with the STO ⟨001⟩ axis, but nearly all are barely located at the substitutional sites due to structural distortion. A minor phase with a tetragonal structure is observed in the Zr distributed region, which has the ⟨001⟩ axis parallel to that of the STO host. The tetragonal phase survived annealing at 1423 K with only a small decrease in the c parameter. A general assessment of the model waste form is also provided in this report.