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Preliminary results on magnetic and transport properties of a thin film of disordered Fe2CrAl deposited on (111) Si by pulsed laser deposition is reported in this study. While the bulk arc melted ingot used as target for the deposition is purely ferromagnetic, the film shows the co-existence of different magnetic phases, which arises due to the granular nature of the film. This is because, although the average composition pertains to Fe2CrAl, local disorder results in the formation of grains with different magnetic states that may be ferromagnetic or may consist of magnetic clusters. The resulting magnetic inhomogeneity of the thin film leads to large values of negative temperature coefficient of resistance of ∼22%/K at 260 K. [ABSTRACT FROM AUTHOR]

Bilayer thin film samples consisting of colossal magnetoresistance manganite La 0.7 Ca 0.3 MnO 3 (LCMO) and superconducting cuprate YBa 2 Cu 3 O 7−δ (YBCO) were stabilized by means of pulsed laser deposition techniques on single crystal SrTiO 3 (001) substrate. The X-ray diffraction measurements confirm the epitaxial relationship of grown bilayer samples. The functional properties of the LCMO/YBCO bilayer were explored through magnetic and electrical transport measurements. The magnetization curve of LCMO/YBCO bilayer sample retains the characteristic ferromagnetic-paramagnetic transition of LCMO and superconducting transition of YBCO. The electrical resistivity was found to show different trend around the superconducting transition depending upon the four probe electrical contacts configuration on bilayer samples and the obtained results lead to direct visualization of proximity effect. A change in sign of magnetoresistance near the superconducting and metal to insulator transition temperature is observed which is attributed to the intrinsic property of YBCO and LCMO layers. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • CdS/CIGS thin films deposited by chemical ion exchange method at room temperature. • Effect of annealing on interface, composition and surface of CdS/CIGS studied. • Annealing at 300 °C suited for modifications of surface, interface and composition. • Increase in conversion efficiency observed from 1.05 to 2.96% upon annealing. Abstract The present article deals with engineering of physicochemical and optoelectronic properties of soft chemical route synthesized CdS/CuInGaSe 2 heterojunction thin films upon air annealing at controlled heating rate of 3 °C/min for 100, 200 and 300 °C with the intension to optimize the post deposition treatment parameter for improvising interface between two layers, so as to obtain controlled stoichiometry (composition) and surface structure modifications. These as deposited and annealed heterojunction thin films were characterized for structural, compositional, morphological, optical and electrical characteristics. The structural pattern obtained from X-ray diffraction pattern (XRD) represents rising of new peaks of (2 1 2), (1 0 5) plane, while widening and shifting of peak position (2 0 5) can be observed on annealing at 300 °C, these planer orientation along with (1 1 2), (2 1 1), (2 1 2), (1 0 5) corresponds to chalcopyrite phase of tetragonal CuInGaSe 2 materials whereas peak at 21.40° and 30.39° represents CdS and ITO substrate material respectively, the average crystallite size found to be increased from 19 nm to 48 nm on annealing treatment. Elemental composition of as deposited heterojunction thin film confirmed by studying energy dispersive X-ray absorption spectrum (EDAX) which shows presence of peaks corresponding to Cu, Cd, Ga, In, Se and S confirming expected elemental composition. Selected area electron diffraction (SAED) pattern obtained from as deposited thin film shows presence of (1 1 2) and (2 1 1) peaks while nanostructured phase confirmed by transmission electron microscopy (TEM) image. Atomic force microscopy (AFM) images of as deposited and annealed samples when compared, represents grain growth in 300 °C annealed sample, this growth may be due to external energy induced grain agglomeration by polygonization process. Optical absorbance spectra shows blue shift in optical absorbance coefficient while extrapolating for energy band gap (Eg) exhibits red shift from 1.48 eV to 1.21 eV upon annealing. The electrical properties when studied on exposing these as deposited and annealed thin films to 100 mW/cm2 light source shows an enhancement in conversion efficiency from 1.05 to 2.96% respectively. [ABSTRACT FROM AUTHOR]

Effect of 100 MeV Au 7+ ion irradiation on structure and optical properties of Cr-doped TiO 2 films has been studied using X-ray photoelectron spectroscopy, soft X-ray absorption spectroscopy, UV-Visible spectroscopy, X-ray reflectivity, and atomic force microscopy. X-ray reflectivity measurement implied that film thickness reduces as a function of ion fluence while surface roughness increases. The variation in surface roughness is well correlated with AFM results. Ion irradiation decreases the band gap energy of the film. Swift heavy ion irradiation enhances the oxygen vacancies in the film, and the extra electrons in the vacancies act as donor-like states. In valence band spectrum, there is a shift in the Ti3d peak towards lower energies and the shift is equivalent to the band gap energy obtained from UV spectrum. Evidence for band bending is also provided by the corresponding Ti XPS peak which exhibits a shift towards lower energy due to the downward band bending. X-ray absorption studies on O Kand Cr L 3,2 edges clearly indicate that swift heavy ion irradiation induces formation of Cr-clusters in TiO 2 matrix. [ABSTRACT FROM AUTHOR]

Thin films of layered perovskites Sr 1.5 RE 0.5 CoO 4 (RE = La, Gd) were grown on MgO (0 0 1) substrate using pulsed laser ablation method. Structural, electrical and magnetic properties of single phase oriented films were studied. Films reveal semiconducting behavior in the entire measured temperature range. The films show thermally activated behavior at high temperature regime, with a higher value of activation energy for SGCO than that for SLCO. The low temperature behavior is well fitted with 3D-variable range hopping mechanism. Both films showed negative magneto-resistance measured in temperature range of 10–200 K. The value of MR is large for SGCO film as compared to its bulk counterpart as well as SLCO film, suggesting its high potential in the spintronics applications. A pinch-shaped M−H behaviour as observed in both the films, suggests the presence of two-magnetic phases. Occurrence of pinch-shape behaviour is although in line with that of SLCO bulk counterpart, interestingly, it was absent in SGCO polycrystalline powder. It suggests major role of film growth kinetics in modifying the magnetic properties in cobaltites. [ABSTRACT FROM AUTHOR]

• TiO 2 thin films deposited using High power Impulse Magnetron Sputtering (HiPIMS) technique. • Phase growth of anatase and rutile analyzed at very Low oxygen partial pressure (0–0.04) using XANES technique. • Comparison of HiPIMS and DCMS grown TiO 2 films. • Anatase, rutile and mix phase confirmed in XRD and Raman and XANES. • FESEM/EDX, AFM used to analyze the morphology and elemental composition of films. • Target poisoning above O 2 partial pressure 0.04. High power impulse magnetron sputtering (HiPIMS) is one of the recent advanced techniques for the development of high quality TiO 2 thin films. Due to the formation of high energetic ions in the discharge, HiPIMS can produce various crystalline phases of TiO 2 (anatase and rutile) with low roughness as compared to conventional direct current magnetron sputtering (DCMS). This work emphasizes on the effect of oxygen partial pressure in the evolution of phases and oxidation states of TiO 2 films deposited using HiPIMS along with a comparative study against DCMS grown films under similar oxygen environment. TiO 2 thin films were prepared with DCMS and HiPIMS, as a function of oxygen content in the sputter gas flow. Thickness, density and roughness were calculated using XRR fitting and analysis. It was observed that HiPIMS deposited films were smoother and denser than DCMS grown films. Crystallite sizes of HiPIMS deposited films were significantly lower than DCMS. Phase growth analyses were performed using X-ray diffraction (XRD), Raman and XANES (X-ray absorption near-edge spectroscopy of the Ti L 2,3 and O K-edges) spectroscopy. In HiPIMS grown films, the increase in O 2 partial pressure changed the phase from rutile to mixed and then to anatase phase whereas only rutile and mixed phases were detected in DCMS grown film under similar oxygen environment. HiPIMS developed films were smooth, uniform free from cracks as observed in FESEM and Atomic Force microscope (AFM) morphological images. Lognormal crystallite size distribution values decreased with increasing O 2 partial pressure. Crystal field splitting values of (Δ o) between ∼1.9 and 2.2 eV indicate crystalline phase formation by XANES Ti L 2,3 -edge analysis. These findings point to better crystalline growth TiO 2 thin films as compared to DC-MS. HiPIMS grown films shows phase transformation of rutile into mix phase and anatase with increase in oxygen partial pressure. [ABSTRACT FROM AUTHOR]

Abstract: We have studied the influence of oxygen partial pressure (OPP; 250mTorr–1×10−5 Torr) and Fe doping (2 and 4at.%) on structural and electrical properties of TiO2 thin films on LaAlO3 substrates. X-ray photoelectron spectroscopy suggests that Fe is not in metal cluster form. It is found that the evolution of the three phases; anatase, rutile and brookite of TiO2 as well as the magneli phase (Ti n O2n−1) strongly depends on the OPP and Fe doping concentration. All the films grown at 250mTorr show insulating behavior, whereas films grown at 1×10−2 and 1×10−4 Torr reveal high temperature metallic to low temperature semiconducting transition. Interestingly, films deposited at 1×10−5 Torr reveal charge ordering, which is contributed to the magneli phase of TiO2. The present study suggests that functionality of TiO2 thin film based devices can be tuned by properly selecting the OPP and dopant concentration. [Copyright &y& Elsevier]

An ion-beam sputtering (IBS) system has been designed and developed for preparing thin films and multilayers of various elements, alloys and compounds. The ion source used is a 3 cm diameter, hot-cathode Kaufman type 1.5 kV ion source. The system has been successfully tested with the deposition of various materials, and the deposition parameters were optimised for achieving good quality of thin films and multilayers. A systematic illustration of the versatility of the system to produce a variety of structures is done by depositing thin film of pure iron, an alloy film of Fe–Zr, a compound thin film of FeN, a multilayer of Fe–Ag and an isotopic multilayer of 57FeZr/FeZr. Microstructural measurements on these films using X-ray and neutron reflectivity, atomic force microscopy (AFM), and X-ray diffraction are presented and discussed to reveal the quality of the microstructures obtained with the system. It is found that in general, the surface roughnesses of the film deposited by IBS are significantly smaller as compared to those for films deposited by e-beam evaporation. Further, the grain size of the IBS crystalline films is significantly refined as compared to the films deposited by e-beam evaporation. Grain refinement may be one of the reasons for reduced surface roughness. In the case of amorphous films, the roughness of the films does not increase appreciably beyond that of the substrate even after depositing thicknesses of several hundred angstroms. [Copyright &y& Elsevier]

We have studied the electronic and magnetic properties of SrRuO 3 thin films deposited by pulse laser deposition on SrTiO 3 (100) substrate. X-ray diffraction and reciprocal space mappings show the epitaxial nature of the thin films and the formation of different structural phase such as tetragonal and tetragonal + monoclinic phase with oxygen partial pressure. In magnetization versus temperature behaviour we observed the large variation in Curie temperature with oxygen partial pressure. These variations are attributed to the defect induced modification in the local structure comprising RuO 6 octahedra. [ABSTRACT FROM AUTHOR]

Zero field cooled spontaneous exchange bias (SEB) is observed in self-assembled nanocomposite thin films of La 0.7 Sr 0.3 MnO 3 (LSMO):NiO grown on single crystal line SrTiO 3 (001) substrate by pulsed laser deposition. SEB is displayed by the asymmetry in the hysteresis loop of the composite film along with the field cooled conventional exchange bias (CEB) effect. The training effect shows that exchange bias relaxation is disorder mediated. It is revealed from DC magnetization measurements that such nanocomposite film divulges spin glass like behaviour, arising due to competing ferromagnetic and antiferromagnetic interactions at the assorted interfaces of ferromagnetic LSMO and antiferromagnetic NiO. X-ray magnetic circular dichroism (XMCD) measurements discern that SEB is mainly originating due to ferromagnetic coupling of unstable interfacial antiferromagnetic spin due to NiO with the ferromagnetic LSMO at the disordered interface. These results of self-assembled thin films provide a useful input to realize and understand microscopic origin of SEB for device application. • Self-assembled nanocomposite thin films of La 0.7 Sr 0.3 MnO 3 (LSMO):NiO grown on SrTiO 3 (001). • Zero field cooled spontaneous exchange bias (SEB), field cooled conventional exchange bias (CEB). • The training effect shows that exchange bias relaxation is disorder mediated. • Magnetization measurements reveals the presence of interfacial disordered glass like behaviour. [ABSTRACT FROM AUTHOR]

Abstract We studied CrN thin films grown by a reactive direct current magnetron sputtering process. Starting with pure Cr, as nitrogen is added, initially N atoms occupy interstitial positions in bcc Cr and when the amount of N increases an amorphous structure emerge. Subsequently, fcc chromium mononitride (CrN) phase start to appear and stoichiometric CrN get formed when the amount of reactive nitrogen gas is about one-third of argon gas. While, the long range ordering of CrN film seems to be stable up to 873 K, signatures of local instabilities can be seen in the N K-edge absorption pattern at lower temperatures. To improve the thermal stability of CrN films, we used oxygen (O) as a surfactant. We found that O works like a surfactant when used in a minuscule amount (0.25%). In the O surfactant mediated growth, O does not react with CrN film. An accumulation of O at the surface of CrN film can be seen in the O K-edge absorption pattern, typically expected in surfactant mediated growth. However, when the amount of O gas flow is increased from 0.25 to 0.5%, it no longer acts as a surfactant and severely affects both long and short range structure of CrN film as occurrence of Cr 2 O 3 phase can now be seen. Surfactant mediated CrN films clearly show denser and smoother films with superior thermal stability. Highlights • CrN thin films grown by reactive magnetron sputtering have been studied. • The mechanism for formation of stoichiometric CrN phase was obtained. • N K-edge absorption spectra reveals thermal instabilities in CrN films. • By using O as a surfactant, resulting CrN films are superior. • Thermal stability of CrN films improve when O is used as a surfactant. [ABSTRACT FROM AUTHOR]

In this work, we studied amorphous carbon ( a -C) thin films deposited using direct current (dc) and high power-impulse magnetron sputtering (HiPIMS) techniques. The microstructure and electronic properties reveal subtle differences in a -C thin films deposited by two techniques. While films deposited with dcMS have a smooth texture typically found in a -C thin films, those deposited with HiPIMS consist of dense hillocks surrounded by a porous microstructure. The density of a -C thin films is a decisive parameter to judge their quality. Often, x-ray reflectivity (XRR) has been used to measure the density of carbon thin films. From the present work, we find that the determination of density of carbon thin films, especially those with a thickness of few tens of nm, may not be accurate with XRR due to a poor scattering contrast between the film and substrate. By utilizing neutron reflectivity in time of flight mode, it has been shown that the density of carbon films can be measured more accurately. Prime novelty statement In this work, we have studied amorphous carbon ( a -C) thin films prepared by direct current and high power impulse magnetron sputtering (dcMS and HiPIMS). We did precise density measurements using time of flight (ToF) neutron reflectivity (NR), a technique seldom used to study carbon thin films. We amply demonstrate limitation of x-ray reflectivity technique generally used for determination of density of thin carbon films. It is expected that our demonstration of NR in density determination of carbon thin film will turn out to be landmark for carbon film community and will certainly be helpful in enriching the related research work. [ABSTRACT FROM AUTHOR]

Herein, ZnMgS nanorod (NR) thin film has been grown by facile single step chemical bath deposition technique. Initially, vertically aligned ZnMgS NR having ∼3 µm length and diameter of ∼200 nm were deposited on commercial glass substrate. The morphology characterizations of this nanorod thin film were observed by FE-SEM and TEM. The randomly oriented hexagonal type nanorods were grown on the glass surface. The strong and highly intense (0 0 2) peak in the XRD pattern along with the calculated low compressive strain indicates vertical growth of high-quality crystalline ZnMgS nanorods. The films showed a direct band transition at ∼3.62 eV. The photosensing properties of NR thin film of ZnMgS showed an excellent photoresponsivity of 34.6 μA/Watt and photosensitivity 99% respectively under illumination of 100 W/cm 2 at a bias voltage 5 V. The obtained experimental results were found to be consistent with theoretical results obtained using DFT. [ABSTRACT FROM AUTHOR]

• Stoichiometric hexagonal Sr0.6Ba0.4MnO3 films are grown. • Raman spectroscopy indicates towards octahedral distortion due to strain. • Weak ferromagnetic behavior is observed at room temperature with high TC. • XMCD measurement confirms weak ferromagnetism at room temperature. • Orbital moment is unquenched and has significant contribution in magnetization. We have probed the effect of intrinsic strain on the structural and magnetic properties of magneto-electric hexagonal Sr 0.6 Ba 0.4 MnO 3 (SBMO) thin film grown by pulsed laser deposition on LaAlO 3 (1 1 0) substrate by varying oxygen partial pressure (OPP). While the grown films show hexagonal structure with varying OPP, transition from oriented to polycrystalline growth is observed with increase in OPP. Raman spectroscopy confirms the P 6 3 / mmc symmetry of grown films along with the indication of distortion of octahedral. Magnetization measurements reveal room temperature weak ferromagnetic behavior in the thin films, which is in contrast to antiferromagnetic nature of its bulk counterpart. X-ray magnetic circular dichroism measurement confirms weak ferromagnetic behavior with contribution from unquenched orbital magnetic moment. [ABSTRACT FROM AUTHOR]

Fe (4 at.%) doped europium (III) oxide thin film was deposited on silicon (1 0 0) substrate by pulsed laser deposition technique. Structural, spectral and magnetic properties were studied by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and magnetization measurements. XRD and Raman spectroscopy reveal that the grown film is single phased and belongs to the cubic structure of Eu 2 O 3 . XPS study of the Eu 1.92 Fe 0.08 O 3 film shows that Fe exists in Fe 3+ ionic state in the film. The film exhibits magnetic ordering at room temperature. [ABSTRACT FROM AUTHOR]

We have investigated TiO 2 films prepared by pulsed laser deposition method on Si(1 1 1) surface using X-ray diffraction (XRD), Raman Spectroscopy, X-ray Photoelectron Spectroscopy (XPS), Atomic Force Microscopy (AFM) and ion beam sputtering techniques. Our XRD data along with Raman indicated that the deposited TiO 2 is in anatase phase. The binding energy position of Ti 2p also supports the anatase phase formation. AFM topography of as deposited film indicates the formation of non uniform TiO 2 growth with the formation of voids on Si(1 1 1) substrate. After sputtering with argon ion beam, surface erosion occurs and voids have disappeared. The Ti 2p core level of sputtered TiO 2 exhibits the formation of Ti 2 O 3 , TiO and pure Ti on the surface. High binding energy shoulder of O 1s peak becomes sharp after sputtering. Ti LMM Auger peaks become broader after sputtering but no shift in kinetic energy is observed. [ABSTRACT FROM AUTHOR]

Nanoparticles of Mn 0.2 Zn 0.8 Fe 2 O 4 were chemically synthesized by co-precipitating the metal ions in aqueous solutions in a suitable alkaline medium. The identified XRD peaks confirm single phase spinal formation. The nanoparticle size authentication is carried out from XRD data using Debye Scherrer equation. Thin film fabricated from this nanomaterial by pulse laser deposition technique on quartz substrate was characterized using XRD and Raman spectroscopic techniques. XRD results revealed the formation of high degree of texture in the film. AFM analysis confirms nanogranular morphology and preferred directional growth. A high deposition pressure and the use of a laser plume confined to a small area for transportation of the target species created certain level of porosity in the deposited thin film. Magnetic property measurement of this highly textured nanocrystalline Mn–Zn ferrite thin film revealed enhancement in properties, which are explained on the basis of texture and surface features originated from film growth mechanism. [ABSTRACT FROM AUTHOR]

Patterned nano crystalline ZnFe 2 O 4 thin film was fabricated on quartz substrate by pulse laser deposition. XRD and Raman spectroscopic techniques were employed for structural characterization of the film. Silencing of a small number of prominent ferrite XRD peaks in thin film signify mild textured film growth. The observed XRD peak position swing with respect to the target material in thin film indicates formation of lateral strain in opposite directions during film growth. The thin film XRD peak position shift with target material data as reference is explained by suggesting an appropriate film growth model. Designated ferrite Raman emission peaks originated from film surface authenticates the stoichiometric and structural stability of ferrite material. AFM images indicate specific pattern formation with nanogranular morphology. Magnetic property measurements of the thin film revealed enhanced properties which are explained on the basis of texture, lattice strain, and surface features that are originated from patterned thin film growth. [ABSTRACT FROM AUTHOR]

• Oxygen vacancies (V O) in SrRuO 3 (SRO) lead to enhanced correlation strength (U/W). • V O causes a reduced DOS at E F and reduced internal magnetic field strength. • Resistivity upturn at low temperatures is observed in SRO thin-film owing to V O. • Quantum effects are observed in Oxygen- deficient SRO thin-film. • At low temperatures, WL prevails over REEI in oxygen-deficient SRO thin-film. [Display omitted] Herein, the electronic, magnetic, and transport properties of an oxygen-deficient epitaxial SrRuO 3 (SRO) thin film have been investigated. The oxygen vacancies (V O) in the SRO thin-film transform a fraction of Ru4+ ions into Ru3+, resulting in an enhancement of the unit cell volume. Due to the elongated lattice parameters, the electronic bandwidth decreases and gives rise to the enhanced correlation strength. Further, distinctive effects of V O are seen in the temperature-dependent resistivity behavior [ ρ (T)]. At low temperatures, the SRO thin film exhibits a resistivity minima near 48 K along with the ferromagnetic to paramagnetic transition (T C ~ 150 K). The resistivity upturn at low temperatures is analyzed using quantum correction in the conductivity and it is found that the weak localization prevails over renormalized electron-electron interactions in the low-temperature resistivity upturn behavior of oxygen-deficient (V O) SRO thin film. [ABSTRACT FROM AUTHOR]

Abstract: Cd doped ZnO (Cd:ZnO) thin films on the glass substrate prepared by chemical spray pyrolysis technique have been characterized for their optical and electrical properties. The X-ray diffraction and atomic force microscopy results indicate that the crystalline quality degrade due to higher Cd doping in ZnO. The activation energy was found to be decreased when Cd concentration increased. The absorption edge of Cd:ZnO film was found to be red shifted. The direct modulation of band gap caused by Zn/Cd substitution is responsible for the red shift effect in absorption edge of ZnO. The low temperature conduction has been explained by variable range hoping mechanism, which fits very well in the temperature range from 108K to 301K. The interaction between Cd and defects in ZnCdO alloy to understand the important roles of Cd in the formation of native defects has also been tentatively discussed. [Copyright &y& Elsevier]

Abstract: NiO nanoparticle films (200nm thick) grown on Si substrates by pulsed laser deposition method were irradiated by 200MeV Ag15+ ions. The films were characterized by glancing angle X-ray diffraction, atomic force microscopy and optical absorption spectroscopy. Though electronic energy loss of 200MeV Ag ions in NiO matrix was higher than the threshold electronic energy loss for creation of columnar defects, films remained crystalline with the initial fcc structure even up to a fluence of 5×1013 ionscm−2, where ion tracks are expected to overlap. Irradiation however modified the microstructure of the NiO films considerably. The grain size decreased with increasing ion fluence, which led to reduced surface roughness and increased optical band gap due to quantum confinement. These results correlate well with variation of the power spectral density exponent with ion fluence, which indicate that at high ion fluences, the evolution of surface morphology is governed by surface diffusion. [Copyright &y& Elsevier]

Abstract: Nanocrystalline indium oxide (INO) films are deposited in a back ground oxygen pressure at 0.02mbar on quartz substrates at different substrate temperatures (T s) ranging from 300 to 573K using pulsed laser deposition technique. The films are characterized using GIXRD, XPS, AFM and UV–visible spectroscopy to study the effect of substrate temperature on the structural and optical properties of films. The XRD patterns suggest that the films deposited at room temperature are amorphous in nature and the crystalline nature of the films increases with increase in substrate temperature. Films prepared at T s ≥473K are polycrystalline in nature (cubic phase). Crystalline grain size calculation based on Debye Scherrer formula indicates that the particle size enhances with the increase in substrate temperature. Lattice constant of the films are calculated from the XRD data. XPS studies suggest that all the INO films consist of both crystalline and amorphous phases. XPS results show an increase in oxygen content with increase in substrate temperature and reveals that the films deposited at higher substrate temperatures exhibit better stoichiometry. The thickness measurements using interferometric techniques show that the film thickness decreases with increase in substrate temperature. Analysis of the optical transmittance data of the films shows a blue shift in the values of optical band gap energy for the films compared to that of the bulk material owing to the quantum confinement effect due to the presence of quantum dots in the films. Refractive index and porosity of the films are also investigated. Room temperature DC electrical measurements shows that the INO films investigated are having relatively high electrical resistivity in the range of 0.80–1.90Ωm. Low temperature electrical conductivity measurements in the temperature range of 50–300K for the film deposited at 300K give a linear Arrhenius plot suggesting thermally activated conduction. Surface morphology studies of the films using AFM reveal the formation of nanostructured indium oxide thin films. [Copyright &y& Elsevier]

Abstract: Modified chemical bath deposited (MCBD) bismuth sulphide (Bi2S3) thin films’ structural, optical and electrical properties are engineered separately by annealing in air for 1h at 300°C and irradiating with 100MeV Au swift heavy ions (SHI) at 5×1012 ions/cm2 fluence. It is observed that the band gap of the films gets red shifted after annealing and irradiation from pristine (as deposited) films. In addition, there is an increase in the grain size of the films due to both annealing and irradiation, leading to the decrease in resistivity and increase in thermoemf of the films. These results were explained in the light of thermal spike model. [Copyright &y& Elsevier]

Abstract: We present a study on the effect of swift heavy ions irradiation on the structural and magnetic properties of Mg0.95Mn0.05Fe2O4 ferrite thin film grown by pulsed laser deposition technique. X-ray diffraction (XRD) pattern of the as-deposited film reveals a cubic spinel structure with an intermediate phase of α-Fe2O3. This impurity phase completely dissolves upon irradiation with 200 MeV Ag15+-ions and it exhibits a strong crystallographic texture along the (440) plane. The magnetization values start increasing systematically with irradiation at lower fluence values, whereas decrease for higher one. This decrease in magnetic signal can be attributed to partial amorphization caused by irradiation in agreement with XRD and atomic/magnetic force microscopic images. [Copyright &y& Elsevier]

Abstract: Zinc oxide thin films are grown by successive ionic layer adsorption and reaction technique at room temperature. The as-grown films were annealed at different temperatures, viz. 350, 400, 450, and 500°C in air atmosphere for 2h. Effect of annealing on the physical properties of ZnO thin films has been studied. XRD analysis reveals the polycrystalline nature for ZnO thin films with hexagonal phase. The films were highly oriented along (100) and (101) planes, an enhancement in these peaks is the significance of the post-deposition annealing treatment on ZnO thin films. The optical studies of the samples show that the energy band gap was decreased in accordance with the annealing temperature. The results of optical studies were strengthened by photoluminescence (PL) studies. [Copyright &y& Elsevier]

Abstract: Systematic studies of thin silicon carbide (SiC) films deposited on Si (100) substrates using pulsed laser deposition technique at room temperature, 370 °C and 480 °C are carried out. X-ray photoelectron spectroscopy showed the formation of SiC bonds in the films at these temperatures along with some graphitic carbon clusters. Fourier transform infrared analysis also confirmed the formation of SiC nanocrystallites in the films. Transmission electron microscopy and electron diffraction were used to study the structural properties of nanocrystallites formed in the films. Surface morphological analysis using atomic force microscopy revealed the growth of smooth films. [Copyright &y& Elsevier]

Abstract: We report on study of morphology, optical contrast and transport characteristics of La0.7Ba0.3MnO3 (LBMO) manganite thin films bilayered with SnO2 on Si (001) substrate, synthesized using pulsed laser deposition system. X-ray diffraction study reveals that both LBMO and SnO2 show polycrystalline growth over the substrate. Atomic force microscopy shows interesting pyramidal structures of LBMO of size ∼2μm×1μm×0.1μm. On the other hand, SnO2 grows in the form of close packed cylindrical clusters of ∼200nm radius. Near-field optical microscopy (NSOM) study using 532nm laser reveal that optical NSOM output intensity in LBMO is four times less than SnO2 signal. Transport characterizations show that this bilayer configuration exhibit non-linear current–voltage characteristics from 300 upto 50K. The nature becomes linear below this temperature. The results project the system as a promising candidate in non-conventional device category in the area of spintronics. [Copyright &y& Elsevier]

Abstract: Thin films of silicon carbide (SiC) were prepared using pulsed laser deposition (PLD) on Si(100) substrates at a temperature of 370°C. Various structural characterizations showed the development of short-range SiC precipitates in the films. These films were annealed isochronally at temperatures of 800°C, 1000°C and 1200°C for 2h under an inert environment. Thermally induced crystalline ordering of SiC into β-SiC phase was investigated by X-ray diffraction (XRD), Raman spectroscopy and Fourier transforms infrared (FTIR) spectroscopic measurements. In addition to the crystallization of SiC films, high temperature annealing resulted in the dissolution of carbon clusters found in the as-grown films. [Copyright &y& Elsevier]

Abstract: Thin films of CdS, Bi2S3 and composite CdS–Bi2S3 have been deposited using modified chemical bath deposition (M-CBD) technique. The various preparative parameters were optimized to obtain good quality thin films. The as-deposited films of CdS, Bi2S3 and composite were annealed in Ar gas at 573K for 1h. A comparative study was made for as-deposited and annealed CdS, Bi2S3 and composite thin films. Annealing showed no change in crystal structure of these as-deposited films. However, an enhancement in grain size was observed by AFM studies. In addition change in band gap with annealing was seen. A study of spectral response, photosensitivity showed that the films can be used as a photosensor. [Copyright &y& Elsevier]

This study aims towards a systematic reciprocity of the tunable synthesis parameters - partial pressure of N 2 gas, ion energy (E i) and Ti interface in TiN thin film samples deposited using ion beam sputtering at ambient temperature (300 K). At the optimum partial pressure of N 2 gas, samples were prepared with or without Ti interface at E i = 1.0 or 0.5 keV. They were characterized using x-ray reflectivity (XRR) to deduce thickness, roughness and density. The roughness of TiN thin films was found to be below 1 nm, when deposited at the lower E i of 0.5 keV and when interfaced with a layer of Ti. Under these conditions, the density of TiN sample reaches to 5.80(± 0.03) g cm−3, a value highest hitherto for any TiN sample. X-ray diffraction and electrical resistivity measurements were performed. It was found that the cumulative effect of the reduction in E i from 1.0 to 0.5 keV and the addition of Ti interface favors (111) oriented growth leading to dense and smooth TiN films and a substantial reduction in the electrical resistivity. The reduction in E i has been attributed to the surface kinetics mechanism (simulated using SRIM) where the available energy of the sputtered species (< E sp >) leaving the target at E i = 0.5 keV is the optimum value favoring the growth of defects free homogeneously distributed films. Secondary ion mass spectroscopy depth profile measurements confirm the uniform distribution of N and Ti across the depth of a sample. The electronic structure of samples was probed using N K-edge and Ti L-edge absorption spectroscopy and the information about the crystal field and spin-orbit splitting confirmed TiN phase formation. In essence, through this work, we demonstrate the role of < E sp > and Ti interface in achieving highly dense and smooth TiN thin films with low resistivity without the need of a high temperature or substrate biasing during the thin film deposition process. • Synthesis and study of TiN(111) thin films using ion beam sputtering is reported. • TiN films were grown at ambient temperature (300 K) without applying any bias. • Tuning of ion energy and a Ti interface has resulted in densest TiN films, hitherto. • TiN films grown at low ion energy on Ti, were densest and smoothest. • SRIM simulations were made to understand the role of sputtered species energy on film growth. [ABSTRACT FROM AUTHOR]

• Fe-doped TiO 2 amorphous thin films deposited using rf magnetron sputtering. • Band-gap energy reduction with Fe doping due to oxygen vacancy. • Maximum Fe substitution is up to 2 at. % doping. The present study deals with the local structure of amorphous TiO 2 and Fe-doped TiO 2 thin films deposited on Si substrate using magnetron sputtering. The absence of long range order is confirmed by grazing incidence x-ray diffraction and the short range order is studied using x-ray absorption near edge structure (XANES) measurements at Ti, Fe and O K-edges and Fe and Ti L 3 -edge. The XANES provides understanding about the electronic transition induced from the short range ordering and dependence of electronic hybridization of the central Ti- p orbitals with the Ti- d orbitals. The XANES measurements also show that maximum Fe doping concentration allowed to replace Ti is 2 at.% and after that separate phase starts appearing, which is consistent with simulation by ab-initio multiple scattering theory based code FEFF9. Ellipsometry measurements show gradual decrease in band-gap energy upto 2 at.% Fe doping from pristine TiO 2 , however a drastic decrease in band-gap energy is observed at 4 at.% or higher doping concentration due to formation of other phases. [ABSTRACT FROM AUTHOR]

Abstract: Zn 0.965 Cd 0.035 O/ZnO bilayer film has been developed using pulsed laser deposition (PLD) technique. The film is characterized by X-ray diffraction (XRD), energy dispersion analysis by X-ray (EDAX), UV-Vis and Valence band spectra (VBS). The XRD pattern confirms the single phase crystalline nature of the deposited film. The UV-Vis spectra establish a reduction of band gap (≈340meV) in the ternary alloy film of Zn 0.965 Cd 0.035 O/ZnO. The VBS shows shift in the peak corresponding to nonbonding oxygen p states. We also obtained valence band offset of 191meV in the film showing the rise of valence band. The calculated conduction band offset is found to be −51meV which confirms the lowering of the conduction band in the ternary alloy film. [Copyright &y& Elsevier]