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[Display omitted] • Effect of different ion fluences (1 × 1013 and 3 × 1013 ions/cm2) of swift heavy ion irradiation (120 MeV Ag+9) on Co/Pt multilayers have been studied. • Ion irradiation with different ion fluences has been found to have different effects on structural and magnetic properties of these multilayers. • Lower fluence has been found to induce ordering in films while higher fluence destroys that ordering. • Controlling the magnetic properties of Co/Pt multilayers by SHI is important for magnetic storage point of view. The integration of CoPt nanoparticles into an insulating matrix has garnered significant attention in material science, nanotechnology, and electronic engineering, particularly for their potential use in magnetic storage media. Precise control over the size, shape, and ordering of these nanoparticles is crucial. This study investigates the impact of swift heavy ion irradiation (120 MeV Ag+9) with varying ion fluences (1 × 1013 and 3 × 1013 ions/cm2) on the structural and magnetic properties of sputter-deposited Co/Pt multilayer thin films on quartz substrates. X-ray diffraction (XRD) analysis of the pristine samples reveals the presence of an FCC-structured CoPt alloy. In contrast, films irradiated with a fluence of 1 × 1013 ions/cm2 exhibit superlattice peaks (0 0 1) and (1 1 0), indicative of L 1 0 -structured CoPt alloy, whereas films subjected to 3 × 1013 ions/cm2 retain the FCC structure. This suggests that a fluence of 1 × 1013 ions/cm2 promotes ordering, while 3 × 1013 ions/cm2 induces disordering. Selected area electron diffraction (SAED) patterns from TEM confirm these structural transitions, while SQUID magnetometry reveals an increase in coercivity at 1 × 1013 ions/cm2, followed by a reduction at 3 × 1013 ions/cm2, consistent with the observed structural changes. These results demonstrate that carefully controlled ion fluences can effectively tailor the structural and magnetic properties of Co/Pt multilayers, enhancing their suitability for advanced magnetic storage applications. [ABSTRACT FROM AUTHOR]

Present work investigates the annealing effects on MgO thin films deposited using e-beam evaporation method. MgO thin films of thickness 5 and 50 nm were evaporated from MgO-pellet in ultra-high vacuum (2×10-8 Torr). As deposited thin films exhibit coordination similar to MgO bulk as envisaged from near edge X-ray absorption fine structure measurements. As deposited films were annealed at 300, 400 and 500oC in open environment. Thickness of films remain unaltered with annealing within experimental error. Raman spectroscopic measurements further confirm the presence of bands associated with Mg-O bonding at such low thicknesses.

Thin Ca F 2 targets with carbon backing are fabricated for the first time using physical vapour deposition technique at the target laboratory of IUAC, New Delhi to perform a multi nucleon transfer reaction on 10 , 11 B＋40Ca systems using General Purpose Scattering Chamber (GPSC) facility. Ca being an oxidizing material, we have used molecular Ca F 2 as the target material instead of Ca. Using turbo-molecular pump based coating unit (TMPU), carbon is deposited on cleaned glass slide and then Ca F 2 is deposited on diffusion pump based coating unit (DPU). We are successful in fabricating Ca F 2 targets of thickness ≈ 264. 4 μ g/cm 2 on carbon backing of thickness ≈ 21. 5 μ g/cm 2 . The thickness and purity measured by the crystal thickness monitor equipped with the vacuum chamber is verified by different techniques like alpha energy loss, Rutherford Back Scattering (RBS), Electron Diffraction Spectroscopy (EDS) and X-ray Diffraction (XRD). Small impurity level were smeared during the observation and the target is successfully used for nuclear reaction experiment. The fabrication of molecular Ca target is found to be more conducive to experimentation since they exhibit less oxidation and herewith we discuss about fabrication technique, experimentation and characterization. [ABSTRACT FROM AUTHOR]

The peculiarities of the formation of porous membranes based on aluminum oxide obtained by the electrochemical anodization of aluminum foil with the preset topological parameters of pores-capillares (20-220 nm) have been studied. The methods to study the membranes based on nanoporous aluminum oxide are proposed. The developed nanoporous material possesses the properties of screening IR radiation in a spectral range of 8-14 μm (corresponds to the spectral region of thermal radiation of bioobjecs). The membranes based on anodized aluminum foil provide the fulfilling the functions of channeling a high-flow helium ions with an energy of 1.5-2 MeV with the experimentally found coefficient of transmission of more than 60%. [ABSTRACT FROM AUTHOR]

Diluted magnetic semiconductor (DMS) AlN:Cu films were fabricated by implanting Cu + ions into AlN thin films at various ion fluxes. AlN films were deposited on c -plane sapphire by molecular beam epitaxy followed by Cu + ion implantation. The structural and magnetic characterization of the samples was performed through Rutherford backscattering and channeling spectrometry (RBS/C), X-ray diffraction (XRD), Raman spectroscopy, vibrating sample magnetometer (VSM) and SQUID. Incorporation of copper into the AlN lattice was confirmed by RBS, while XRD revealed that no new phase was formed as a result of ion implantation. RBS also indicated formation of defects as a result of implantation process and the depth and degree of damage increased with an increase in ion fluence. Raman spectra showed only E 2 (high) and A 1 (LO) modes of wurtzite AlN crystal structure and confirmed that no secondary phases were formed. It was found that both Raman modes shift with Cu + fluences, indicating that Cu ion may go to interstitial or substitutional sites resulting in distortion or damage of lattice. Although as implanted samples showed no magnetization, annealing of the samples resulted in appearance of room temperature ferromagnetism. The saturation magnetization increased with both the annealing temperature as well as with ion fluence. FC/ZFC measurements indicated that the ferromagnetic effect was not related with superparamagnetic phase formation. In spite, it was due to the formation of AlN based DMS material. The Curie temperature ( T C ) of the sample prepared at an ion fluence of 5 × 10 15 cm −2 and an annealing temperature of 950 °C was found to lie above 340 K. [ABSTRACT FROM AUTHOR]

Pt/Fe3Pt thin films were deposited on the 〈100〉 silicon substrates at room temperature using DC sputtering. As-deposited Pt (25nm)/Fe3Pt (70nm) bilayers were subjected to heat treatment and a systematic study was carried out to investigate the structural and magnetic phase transition as a function of annealing temperature. The as-obtained films show an A1 disordered, face centered cubic phase which exhibit a magnetically soft behavior. After annealing at 300°C for 1h, the set in of L10 face centered tetragonal phase was observed and is attributed to the atomic diffusion at Pt/Fe3Pt interface. A coercivity of 6.8kOe was obtained for Pt/Fe3Pt at 300°C which increases to 12.5kOe at 400°C due to enhanced fct phase formation. Rutherford back scattering study has also been performed to investigate the inter-layer diffusion of Fe3Pt and Pt, along with estimation of film thickness and atomic composition with annealing temperature. The thickness and composition of films annealed at 600°C was found to be 73nm and Fe54Pt46, respectively. Lower temperature ordering is achieved for these bilayer films. [ABSTRACT FROM AUTHOR]

Abstract: Thin films of Cd1−x Mn x Te, a potentially important spintronic material, were fabricated using thermal interdiffusion of MnTe–CdTe bilayers and Mn–Cd–Te trilayers. The impact of the number of repeat layers on the interdiffusion profile was investigated using RBS spectrometry. A working number of layer repetitions were found out for the multilayer structure to produce Cd1−x Mn x Te. Hall measurements of the multilayers supported the conclusions drawn from the RBS data. Magneto-optic Kerr effect studies were also carried out with the optimized multilayers. Apart from single crystal growth, this methodology of fabrication of Cd1−x Mn x Te may serve as a simple process of fabrication of DMS alloy films. [Copyright &y& Elsevier]

Abstract: Ternary cobalt–nickel silicide thin films were synthesized by DC magnetron sputtering from an equiatomic cobalt–nickel alloy target. Grazing incidence XRD, Rutherford back scattering, high-resolution cross-sectional TEM analysis and electrical study were carried out to investigate the formation of silicide, stoichiometry, film thickness, depth profile and sheet resistance of as-deposited and post-deposition annealed films. The ternary silicide layer thickness was calculated from RBS simulated data, which was found to vary 20–43nm for as-deposited and different vacuum annealed films. A minimum value of sheet resistance 2.73Ω/sq corresponding to a resistivity of ∼8.4μΩ-cm was obtained for optimized deposition and annealing conditions. [Copyright &y& Elsevier]

Poly(vinyl phosphate- b-styrene) (PVPP- b-PS) block copolymers were synthesized successfully from poly(vinyl alcohol- b-styrene) (PVA- b-PS) by reaction with phosphorus oxychloride and subsequent hydrolysis. The obtained block copolymers were slightly crosslinked, and were characterized by various analytical techniques. The total phosphorus content and the ratio of the differently bound phosphorus were obtained by both solid-stateP NMR and pH titration, but the results differed slightly. Characterization by energy dispersion X-ray analysis (EDS) or Rutherford back scattering (RBS), on the other hand, determined the total phosphorus contents, but the results were quite different from those by solid-stateP NMR. [ABSTRACT FROM AUTHOR]

Abstract: Thin films of lanthanum sulphide (La2S3) have been deposited onto glass substrates by spray pyrolysis technique from non-aqueous (methanol) medium. The structural, morphological, optical, dielectric, electric and thermoemf properties were studied. The films were polycrystalline with an irregular shaped particles present over the porous structure within a fibrous network structure. The optical band gap was estimated to be 2.50eV. The dielectric properties were measured in the range 100Hz–1MHz. The electrical resistivity was of the order of 104 to 105 Ωcm. Thermoemf study revealed that the La2S3 films exhibit p-type electrical conductivity. [Copyright &y& Elsevier]

Abstract: The oxidation of a 2.7-nm-thick layer of Si formed on a layer of Si0.7Ge0.3 using atomic oxygen at 400°C was studied with the aid of angle-resolved X-ray photoelectron spectroscopy and high-resolution Rutherford backscattering spectroscopy. Analysis of the measurement results revealed that: (1) an appreciable number of Ge atoms diffused into the Si layer during the formation of a 3-nm-thick Si layer on the Si0.7Ge0.3 layer at 720°C; (2) when the entire Si layer was oxidized, 1.8% of the Si layer remained in the SiO2 in the form of Si0.7Ge0.3 alloy; and (3) an abrupt compositional transition took place at the SiO2/SiGe interface. [Copyright &y& Elsevier]

The composition and chemical structures of lanthanum oxide films were determined by combining angle-resolved photoelectron spectroscopy and high resolution Rutherford backscattering studies. Conduction and valence band discontinuity at La2O3/Si(1 0 0) interface was also determined by measuring the O 1s photoelectron energy loss and valence band spectra. [Copyright &y& Elsevier]

Platinum (Pt) thin films were deposited by dual ion beam sputtering (DIBS) techniques on oxidized silicon substrates maintained at ambient temperature. Argon ions with energy of 1 keV and beam current of 15 mA were used to sputter the platinum target. The films during deposition were continuously bombarded by argon from a secondary argon ion source with ion energy of 150 eV and ion current density in the range 100–250 μA/cm2. The influence of the secondary ion beam parameters on the grain size, composition and surface morphology of the films were studied. X-ray diffraction (XRD) of all the films showed (1 1 1) orientation with other reflections being absent which is a stable structure for FCC crystals. The grain size of the Pt films prepared by DIBS at ambient temperature were found to be higher than those prepared at higher substrate temperature by low energy plasma sputtering. The presence of Ar impurities in the sputter deposited thin films is known to modify their properties. In this paper we report a method to control the Ar content in the films by secondary Ar ion bombardment of the growing films. The modification of the surface features by secondary ion beam current was studied by scanning tunneling microscope and is also presented in this paper. The surface analysis indicates a decrease in the surface roughness for the Pt films prepared at a secondary ion beam current density of 150 μA/cm2. [Copyright &y& Elsevier]

The experimental data for Gd2O3, as a typical example of rare earth oxide films, clearly indicate that combination of high resolution RBS and high resolution XPS studies is powerful for the determination of composition and chemical structures of high-k dielectric films. Conduction and valence band discontinuities at rare earth oxide/Si(1 0 0) interfaces were also determined by measuring the O 1s photoelectron energy loss and valence band spectra. [Copyright &y& Elsevier]

Rutherford back scattering (RBS) and elastic nuclear resonance (non-RBS resonance scattering of 3.05 MeV α-particles from oxygen atoms of a sample, for example) have been used for non-destructive characterization of differently fired samples of cadmium oxide (a II–VI semiconductor), Bi2Sr2CaCu2O(8+x) and (Bi0.92Pb0.17)2Sr2CaCu2O(8+x) high temperature superconductors, and practically useful films of a composite of diamond nanoparticles and Si–O made by CV deposition on Si substrate. In the RBS spectrum, steps for light elements like O and Ca are practically not visible, while steps for heavy elements like Bi and Cd are clear and large. In contrast, there is a clear resonance peak due to oxygen allowing easy detection of oxygen in a sample. Most important of our present RBS findings is reduction of O-content from cadmium oxide on firing (here for 36 h) at higher and higher temperatures up to 800 °C. Large variations of room temperature (300 K) electrical resistivity of CdO after heat treatments at different temperatures for 36 h have been explained on basis of variation in O-content. Its room temperature resistivity of 26.4 mΩ cm for firing at 275 °C reduces to only 2.15 mΩ cm for firing at 800 °C. [Copyright &y& Elsevier]