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Rock-salt structured single-phase Ni0.98Fe0.02O and Ni0.93Fe0.02Li0.05O thin films with room temperature ferromagnetism were grown by pulsed laser deposition. It is found that the Li codoping into Ni0.98Fe0.02O significantly increases the saturation magnetic moment by a factor of 2, i.e., from 0.32μB/Fe rising to 0.67μB/Fe. The x-ray absorption fine structure spectral analyses at Fe and O K edge reveal that in both samples, the impurities are substitutionally incorporated into the NiO host. The first-principles calculations show that substitutionally doping Li ions into NiO leads to a strong hybridization between the Fe 3d states and the spin-split acceptor band at the Fermi level. As a result, the Fe 3d electron configuration is altered and the effective magnetic moment per Fe ion is enhanced. [ABSTRACT FROM AUTHOR]

Zn0.96Mn0.04O and Zn0.96Mn0.04O:N thin films with wurtzite structure were grown by inductively coupled plasma enhanced chemical vapor deposition method. Although both samples exhibit ferromagnetism at room temperature, the saturation magnetic moment (1.4μB/Mn) of the Mn- and N-codoped sample is much larger than that (0.3μB/Mn) of the N-free one. The x-ray absorption near edge structure analysis reveals that the codoped Mn and N impurities can be substitutionally incorporated into the ZnO host in the Zn0.96Mn0.04O:N thin film. The first-principles calculations suggest that the N substitution for the O site in Mn-doped ZnO can change the interaction of neighboring Mn–Mn pairs from antiferromagnetic to ferromagnetic, and accordingly the effective magnetic moment per Mn is greatly enhanced. [ABSTRACT FROM AUTHOR]

Highlights: [•] La x Hf(1−x)O y thin films were grown by pulse laser deposition method. [•] The thin film with 10% La/(La+Hf) atom ratio forms a cubic HfO2 phase. [•] The amorphous thin films due to more La introduced have almost same local structure. [•] The main infrared phonon modes move to lower frequency for the amorphous thin films. [•] The static dielectric constants of the amorphous thin films increase with La content. [ABSTRACT FROM AUTHOR]

Abstract: The La2Hf2O7 films have been deposited on Si (100) substrate by using pulsed laser deposition (PLD) method. X-ray diffraction (XRD) demonstrates that the as-grown film is amorphous and crystallizes after 1000°C annealing. The interface structure is systematically studied by Synchrotron X-ray reflectivity (XRR), Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). Silicide, silicate and SiO x formations from interfacial reaction are observed on the surface of the Si substrate in the as-grown film. The impact of silicide formation on the electrical properties is revealed by capacitance–voltage (C–V) measurements. By post-deposition annealing (PDA), silicide can be effectively eliminated and C–V property is obviously improved. [Copyright &y& Elsevier]

Abstract: Y2O3 thin films were grown on silicon (100) substrates by pulsed-laser deposition at different substrate temperatures and O2 pressures. The structure and composition of films are studied by using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The Y2O3 thin films deposited in vacuum strongly oriented their [111] axis of the cubic structure and the film quality depended on the substrate temperature. The magnitude of O2 pressure obviously influences the film structure and quality. Due to the silicon diffusion and interface reaction during the deposition, yttrium silicate and SiO2 were formed. The strong relationship between composition and growth condition was discussed. [Copyright &y& Elsevier]

Highlights: [•] Amorphous and crystalline LaLuO3 thin films were grown by PLD. [•] The infrared phonon modes are kept in the crystalline thin film but reduced in the amorphous thin film. [•] The amorphous thin film has different local structure with crystalline thin film. [•] The changes of phonon modes and dielectric constant are closely related to the local structure. [Copyright &y& Elsevier]

Abstract: The nano-structured ZnO thin film has been grown by molecular beam epitaxy on an Si (100) substrate. The emission spectra of ZnO samples were measured with the photon counting method in the temperature range from 18 to 140K by using the synchrotron radiation up to the vacuum ultraviolet region. Under the excitation of 196nm, two main emission bands have been observed, which peak at 330 and 430nm approximately. The 330nm emission band is due to the radiative recombination of excitons in surfaces associated with the O 2p dangling-bond state, and the 430nm band is attributed to the deep-level emission, which is related to oxygen vacancy defects. The temperature dependence of these two emission bands and the influence of the sample''s annealing on the emission spectrum support our suggestions about the origin of the 330nm emission band as well as the 430nm one. [Copyright &y& Elsevier]