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Abstract: Multicomponent metallic glass films inheriting the superior mechanical properties and wide supercooled liquid regions of their bulk counterparts attract increasing attentions for applications in micro-electro-mechanical systems and nano-devices. In this paper, we systematically investigated the growth of multicomponent metallic glass films synthesized using single-target magnetron sputtering. It was found that the working argon gas pressures (P Ar,) and sputtering power are two key factors governing film growth and composition. At high P Ar, the glassy films grow via a columnar mode, leading to rough film surface. At low P Ar, the films exhibit a negative growth exponent and a nearly atomically flat surface. At appropriate sputtering power and P Ar, the films can completely inherit the composition of alloy targets, which makes it possible to fabricate multicomponent glassy films with controllable composition using single targets. The mechanisms accounting for the growth of the glassy films are discussed in the framework of dynamic scaling theory. The diversely tunable film microstructure and composition are expected to lead metallic glasses towards new functional applications. [Copyright &y& Elsevier]

Abstract: In this paper, we report on the controlling of the effect of growth parameters such as substrate temperature and the ratio of Cr and N atoms on phase formation, surface morphology and crystallization of CrN(001) thin films grown by plasma-assisted molecular beam epitaxy on the MgO(001) substrate. The reflection high energy electron diffraction, atomic force microscopy, X-ray diffraction and scanning tunneling microscopy are used to characterize the thin films grown under various conditions. High-quality CrN(001) thin films are achieved at a substrate temperature 430°C with a low Cr deposition rate. [Copyright &y& Elsevier]

Abstract: The pyrite films with the thickness of 70–600 nm were prepared by annealing the iron films with the thickness of 25–150 nm at 673 K. The structural, optical and electrical characteristics were investigated and the effect of film thickness on film properties was discussed. The pyrite films with different thickness have the optical absorption edges changed in the 0.93–1.0-eV range. With the increase in film thickness, electrical resistivity tends to increase and carrier concentration tends to decrease. It is speculated that surface defects in thinner films could play a more important role in the effect on film properties whereas grain boundary defects in thicker films could play a more important role in the effect on film properties. [Copyright &y& Elsevier]

Pyrite films have been prepared by sulfuration annealing iron films with different sulfur atmosphere pressure at 400 and 500 °C. The optical absorption and electrical characteristics have been determined as a function of the sulfur pressure in the range of 40–100 kPa. For the films sulfurated at 400 °C, with increasing in sulfur pressure, the optical absorption edge increases up to remain a constant value about 0.93 eV while the electrical resistivity shows an insignificant change. By comparison with the films sulfurated at 400 °C with different sulfur pressure, the films sulfurated at 500 °C have high electrical resistivity and low optical absorption edge except for the films sulfurated in 40 kPa sulfur atmosphere. With increasing in sulfur pressure at 500 °C, the carrier density in the films increases and the charge mobility decreases. [Copyright &y& Elsevier]

Co–ZnO inhomogeneous magnetic semiconductor thin films were synthesized on the subnanometer scale by sputtering. Room temperature ferromagnetism with high magnetization was found. Large negative magnetoresistance of 11% was found at room temperature, and its value increased with a decrease in temperature up to 36% at 4.8 K. The mechanism for large negative magnetoresistance is discussed. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Abstract: The incorporation of substitutional carbon (C sub) in low-temperature epitaxial Si1− x − y Ge x C y thin films using SiH4, GeH4 and C2H4 by ultra-high-vacuum chemical vapor deposition was investigated in this work. The Si1− x − y Ge x C y alloys have been grown at a temperature range from 550 to 600°C. The C sub content in Si1− x − y Ge x C y increases with increasing C2H4 partial pressure under the same SiH4 and GeH4 condition. The addition of excessive C2H4 causes the degradation of Si1− x − y Ge x C y crystallinity, surface roughening and the suppression of Ge incorporation. The C–C double bonds in C2H4 were responsible for the highest percentage of C sub, only 0.2%, incorporated in Si0.8− y Ge0.2C y . The Ge, B and C concentration were determined by secondary ion mass spectroscopy (SIMS). The total C atoms incorporation efficiency is ∼0.05. The maximum concentration of C sub in Si1− x − y Ge x C y increases with the decrease of Ge content. In the ambient of hydride-based CVD at low-growth pressure and temperature, the presence of GeH4 would impede the incorporation of C sub in Si1− x − y Ge x C y /Si heterostructure using C2H4 as C source. [Copyright &y& Elsevier]

White-light-controlled resistive switching effect in [BaTiO 3 /γ-Fe 2 O 3 ]/ZnO film was investigated. Resistive switching effect in the [BaTiO 3 /γ-Fe 2 O 3 ]/ZnO film was observed. The resistive switching effect becomes stronger when subjected to white light irradiation. In addition, the resistive switching effect becomes stronger with increase in annealed temperature. At the same time, resistive switching shows a strong dependence on the thickness of the [BaTiO 3 /γ-Fe 2 O 3 ] layer. [ABSTRACT FROM AUTHOR]

Abstract: Annealing studies were performed to investigate the effects of heat treatment on InN thin films by changing the annealing condition from vacuum to high pressure N2. A significant variation of ∼400meV in the surface work function was observed for InN films. The basic principles of Kelvin probe measurement revealed that the surface band bending E SBB is crucial in investigating the significant changes of surface work function on the InN. The stoichiometric ratio imbalance of In and N was indirectly determined to be the main cause of the variation in band bending by analyzing the X-ray diffraction and energy dispersive X-ray measurements. Thus, the annealing treatment could be an effective method to adjust the surface work function of InN by changing the annealing condition from vacuum to high pressure N2. [Copyright &y& Elsevier]

Abstract: The photoluminescence (PL) emission properties of ZnO films obtained on quartz glass substrate by the oxidation of Zn films were studied. The strong single violet emission centering about 413–424nm was observed in the room temperature PL spectra of the ZnO films. The intensity of violet emission increased and the peak position shift from 424 to 413nm with increasing oxygen pressures. The violet emission was attributed to the electron transition from the valence band to interstitial zinc (Zni) level under low oxygen pressure conditions (50–500Pa). Under high oxygen pressure conditions (5000–23,000Pa), both interstitial zinc (Zni) and zinc Vacancy (VZn) were thought to be responsible for the violet emission. [Copyright &y& Elsevier]

Abstract: The room-temperature magnetic properties of CoFeB thin films grown on silicon substrate were investigated. Large perpendicular coercive forces in CoFeB thin films with thickness up to 172nm were observed. The value of the perpendicular coercive force is 1850Oe as the thickness of the CoFeB layer is 38nm. The large perpendicular coercive force indicates the presence of intrinsic perpendicular magnetic anisotropy in thick CoFeB layer with thickness up to 172nm, which originates from (300) texture in CoFeB layer. The strength of perpendicular magnetic anisotropy of CoFeB depends on annealing temperature. [Copyright &y& Elsevier]