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The investigation of semiconductor films of undoped ZnO and doped with two weight percentages of Cadmium (0.5 and 3) were grown on glass and silicon substrates under the same conditions using the dip-coating method. The X-ray diffraction patterns showed the growth of the wurtzite ZnO phase in a hexagonal crystal structure. Also, the effect of both cadmium concentration and substrate type is very clear, while the films those grown on glass substrate showed a crystallization with a highly c-axis preferred (002) orientation, those grown on a silicon substrate showed regular growth in all directions of the zinc oxide phase. The average crystallites size is of the nano-metric scale, more precise about 27 nm, supported with images taken with Environmental Scanning Electron Microscopy, furthermore from the latter technic (ESEM), we noticed a presence of three morphological types on the surface, were originated according to the substrate type and quantity of Cd-doping. The Rutherford Backscattering Spectrometry simulation spectra and the Auger Electron Spectroscopy by the relation with the stripping time emphasize the subsistence of starting (Zn) and doping (Cd) elements on the final specimens and in proportional quantities, to deduce that the undoped ZnO specimen thin film is the thickest. All the obtained films have an optical transmission of about 80% level within the visible range and a severe absorption beginning about 370 nm corresponding to the fundamental absorption limit, where the optical band gap energy decreased from 3.21 eV to 3.16 eV for the undoped ZnO and doped with 3 wt.% Cd respectively. The room-temperature luminescence emission spectra of all specimens were excited at the same conditions under 250 nm Xenon lamp excitation, where showed ultraviolet and visible emissions for all the films grown on a glass and silicon substrate, while an opposite reaction was recorded in the intensity of the spectra as the percentage of Cd increased.

Ion beam induced modification of thin metallic films is an emerging approach to grow metallic nanoparticles controllably. Modification of thin solid films is helpful in fabricating arrays of nanoscale particles for electronic and photonic devices and for the catalyzed synthesis of nanotubes and nanowires. In this work, the modification and nanostructures formation over the surface of SiC/Pd thin films of 15 and 45 nm thicknesses, grown on crystalline Silicon (c-Si) substrate by electron beam deposition, upon ion irradiation, have been investigated by means of scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), Rutherford backscattering spectrometry (RBS), Fourier Transform Infrared Spectroscopy (FTIR) and Raman spectroscopy. The SiC/Pd bilayer films were irradiated with 100 keV Ar+ ions at fluences of 1 × 1015 and 5 × 1015 ions/cm2 at room temperature. The surface morphology from SEM analysis showed the formation of nanoparticles that were interconnected after irradiation. The RBS and EDS results confirmed the presence of Pd, C, O and Si. While the Raman spectrum of the pristine sample displayed only a sharp peak at 520 cm−1 characteristic to c-Si substrate, the spectra of the irradiated sample red-shifted to lower wavenumbers indicating the appearance of Si nanocrystals.. Hence, ion beam irradiation is a promising method for the fabrication of SiC nanostructures on c-Si substrate.

The III–V semiconductor GaN is a promising material for photoelectrochemical (PEC) cells, however the large bandgap of 3.45 eV is a considerable hindrance for the absorption of visible light. Therefore, the substitution of small amounts of N anions by isovalent Sb is a promising route to lower the bandgap and thus increase the PEC activity under visible light. Herein we report a new chemical vapor deposition (CVD) process utilizing the precursors bis(N,N′-diisopropyl-2-methyl-amidinato)-methyl gallium (III) and triphenyl antimony (TPSb) for the growth of GaSbxN1−x alloys. X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements show crystalline and homogeneous thin films at deposition temperatures in the range of 500–800 °C. Rutherford backscattering spectrometry (RBS) combined with nuclear reaction analysis (NRA) shows an incorporation of 0.2–0.7 at% antimony into the alloy, which results in a slight bandgap decrease (up to 0.2 eV) accompanied by enhanced sub-bandgap optical response. While the resulting photoanodes are active under visible light, the external quantum efficiencies remained low. Intriguingly, the best performing films exhibits the lowest charge carrier mobility according to time resolved THz spectroscopy (TRTS) and microwave conductivity (TRMC) measurements, which showed mobilities of up to 1.75 cm2 V−1 s−1 and 1.2 × 10–2 cm2 V−1 s−1, for each timescale, respectively.

Ion beam sputtering is a versatile technique to create nanostructured thin films with precise control over process parameters. We report the properties of graphitic carbon nitride (g-C3N4) thin films deposited by ion beam sputtering. Ion beam analysis methods including Rutherford Backscattering Spectrometry (RBS), Nuclear Reaction Analysis (NRA) and Particle Induced X-ray Emission (PIXE) were used for quantitative determination of composition, thickness, elemental depth profile and trace, major elements and impurities. It was found that by directly using compressed g-C3N4 powders as the sputter target material and tuning the process parameters, g-C3N4 thin films with well controlled deposition rate were obtained. Post-annealing above 250 °C under argon atmosphere for 30 min was needed to recrystallize the g-C3N4 nanostructure. Our results suggest that ion beam sputtering technique is a promising method to obtain uniform and high-quality g-C3N4 thin films.

The unique structural and electronic properties of transition metal dichalcogenides (TMDs) and in particular tungsten disulphide (WS2) make them interesting for a variety of applications such as the electrocatalytic hydrogen evolution reaction (HER) for water splitting devices and chemiresistive gas sensors. The key parameter for the realisation of these devices is the controlled large-area growth of WS2 combined with tuning the surface morphology and electronic properties which is achieved by bottom-up fabrication methods such as chemical vapour deposition (CVD). In this study, 2H-WS2 films are fabricated by a new metal–organic CVD (MOCVD) process resulting in the growth of crystalline, pure, and stoichiometric films which was accomplished at temperatures as low as 600 °C as confirmed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Rutherford backscattering spectrometry (RBS)/nuclear reaction analysis (NRA), and Raman spectroscopy. The surface morphology of WS2 layers was investigated by scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HR-TEM). Following successful process development, the WS2 layers were deposited on conducting FTO/glass substrates and their catalytic activity for the HER was evaluated in a linear sweep voltammetry (LSV) experiment. Furthermore, the temperature-dependent sensor response towards NO2, CO, and NH3 was investigated for WS2 films deposited on special sensor chips, revealing a p-type response towards NO2 and NH3 and sensitivities of around 20% for NO2 and NH3 concentrations of 1.5 ppm and 7.6 ppm, respectively. These promising results demonstrate the effectiveness of scalable CVD-grown WS2 and pave the way for practical applications by modulating the properties of materials to achieve enhanced electrocatalytic and sensing performances employing WS2 layers.

A diffusion kinetics study of implanted silver (Ag) ions into SiC films is conducted. SiC thin films have been processed on Si (1 0 0) substrates by electron beam deposition from a commercial high purity hot-pressed SiC sheet. The as-deposited films were thereafter implanted with Ag+ ions. Realtime Rutherford backscattering spectrometry experiments showed that Ag+ is stable until 600 °C, which is the highest temperature that the heater in the system used could achieve. Conventional RBS studies on isochronally annealed films at higher temperatures in the range between 650 °C and 950 °C reveal that there is no significant change in the spectra up to a temperature of ∼ 750 °C. At 850 °C a change in the Ag implantation profile was observed, suggesting that Ag is mobile at that temperature. The corresponding depth profile at 850 °C suggests that there is significant Ag in- diffusion, however the overall integrated intensity data indicate that most of the Ag+ is escaping out of the films. Upon annealing for one hour at 950 °C, all the Ag ions have essentially escaped out of the films and/or spread throughout the layer below the detection limit of RBS. Isothermal annealing studies over varied duration times at 850 °C confirm Ag in-diffusion, but at the same time there is evidence of depletion of Ag near-surface regions as the annealing time increases; the overall out-diffusion of the implanted metal, although steady, is found to be slow in an isothermal process. FTIR investigations point to a diffusion model through pores and grain boundaries.

Nickel-based nanostructured materials have gained widespread attention, particularly for energy-related applications. Employing chemical vapor deposition (CVD) for NiO necessitates suitable nickel precursors that are volatile and stable. Herein, we report the synthesis and characterization of a series of new nickel β-ketoiminato complexes with different aliphatic and etheric side chain substitutions, namely, bis(4-(isopropylamino)-pent-3-en-2-onato)nickel(II) ([Ni(ipki)2], 1), bis(4-(2-methoxyethylamino)pent-3-en-2-onato)nickel(II) ([Ni(meki)2], 2), bis(4-(2-ethoxyethylamino)pent-3-en-2-onato)nickel(II) ([Ni(eeki)2], 3), bis(4-(3-methoxy-propylamino)-pent-3-en-2-onato)nickel(II) ([Ni(mpki)2], 4), and bis(4-(3-ethoxypropylamino)pent-3-en-2-onato)nickel(II) ([Ni(epki)2], 5). These compounds have been thoroughly characterized with regard to their purity and identity by means of nuclear magnetic resonance spectroscopy (NMR) and electron impact mass spectrometry (EI-MS). Contrary to other transition metal β-ketoiminates, the imino side chain strongly influences the structural geometry of the complexes, which was ascertained via single-crystal X-ray diffraction (XRD). As a result, the magnetic momenta of the molecules also differ significantly as evidenced by the magnetic susceptibility measurements employing Evan's NMR method in solution. Thermal analysis revealed the suitability of these compounds as new class of precursors for CVD of Ni containing materials. As a representative precursor, compound 2 was evaluated for the CVD of NiO thin films on Si(100) and conductive glass substrates. The as-deposited nanostructured layers were stoichiometric and phase pure NiO as confirmed by XRD, Rutherford backscattering spectrometry (RBS), and nuclear reaction analysis (NRA). X-ray photoelectron spectroscopy (XPS) indicated the formation of slightly oxygen-rich surfaces. The assessment of NiO films in electrocatalysis revealed promising activity for the oxygen evolution reactions (OER). The current densities of 10 mA cm-2 achieved at overpotentials ranging between 0.48 and 0.52 V highlight the suitability of the new Ni complexes in CVD processes for the fabrication of thin film electrocatalysts.

CrAlN alloys can play an important role in the improvement of next generation piezoelectric MEMS devices. However, enhanced piezoelectric constants require high degree of uniaxial orientation in the polycrystalline thin film. In this work, CrxAl1−xN thin films with varying compositions were deposited at different substrate temperatures by reactive DC co-sputtering technique and compared with respect to their microstructure and optical properties. The relationship between the atomic composition of the layers and the plasma powers over the Al and Cr targets during co-sputtering was revealed accurately by Rutherford backscattering spectrometry. As it was found by X-ray and selective area electron diffraction methods, thin films in the range of x = 0–0.23 show hexagonal wurtzite-type phase, which changes to cubic rock-salt-type structure between 0.23

Nanostructured thin films of CuO were deposited on silica glass substrates using reactive DC magnetron sputtering technique. Microstructural, morphological, optical, catalytic and photocatalytic properties of the prepared CuO thin films were examined using FESEM, AFM, Rutherford backscattering spectrometry, XRD, XPS, UV–Vis absorption and PL spectroscopy. FESEM showed nanostructures in the thin films, which were confirmed to be of monoclinic CuO by XRD analysis. Substrate temperature variation (40 °C, 100 °C and 300 °C) was found to significantly alter the optical, morphological, photocatalytic and structural properties of the CuO nanostructured thin film coatings. FESEM and AFM analyses showed decrease in size of nanostructures and surface roughness increase with increase in substrate temperature. Increase in UV–Vis absorbance and PL intensity of CuO thin films with decrease in crystallite size were noticed as the substrate temperature was increased. The prepared nanostructured CuO thin films exhibited highly enhanced photocatalytic activities and degraded dyes (MB and MO) in water in just 40 min under solar exposure and catalytic transformation of 4-nitrophenol (4-NP) took place in just 15 min. The developed CuO nanostructured thin film coatings are very promising for large scale, practical and advanced catalytic reduction of toxic 4-NP and photocatalytic applications in solar driven water purification.

The specimens of nanostructured semiconductor of Zn1-xCdxO (0 ≤ x ≤ 0.1) thin films were grown on silicon substrate using a dip-coating method. The sol-gel technique was used. The appropriate amounts of Zinc acetate dihydrate (ZnAc) and the Cadmium acetate dihydrate (CdAc) were mixed according to the weight ratios that we have identified as follows; 0, 1, 2, 5 and 10 wt.%, then dissolved in 2-Methoxyethanol. Moreover, the Ethanolamine acts as a stabilizer. All films were annealed for 2 h at 500 °C. In order to search the Cd doping effect and its behavior to understand the morphological, structural and optical characteristics with confirm the presence of components and calculate its atomic percentages, we were used many nuclear techniques. The X-ray patterns of all films have showed a hexagonal structure crystallization of wurtzite ZnO phase with nano-metric crystallites size, about 25 nm, confirmed by an Environmental Scanning Electron Microscopy (ESEM) images, also we observed the fibers or a roots-like morphology on the surface. The Auger Electron Spectroscopy (AES) by the relation with the etching time and the Rutherford Backscattering Spectrometry (RBS) simulation spectra confirmed the existing of starting and doping elements, to conclude in the latter that the sample of ZnO film doped 10 wt.% Cd has the thickest. Regarding the Photoluminescence (PL) property and under the excitation of 250 nm by Xenon lamp in the room-temperature, the films showed a luminescence spectra of ultraviolet and visible emission, and we remarked also an increasing intensity of this latter up to 5 wt.% Cd doping, as well as a decrease of the optical gap energy has been registered from 3.33 to 3.25 eV with the increase of cadmium doping concentration.

Manganese-doped zinc oxide (Mn-doped ZnO) thin films were synthesized on soda lime glass substrates using the spray pyrolysis technique at substrates temperatures of 400, 450 and 500 °C. Compositional, optical, structural, morphological and electrical properties were studied with Rutherford Backscattering Spectrometry (RBS), Ultraviolet and Visible Spectroscopy (UVS), X-Ray Diffraction (XRD) analysis, Scanning Electron Microscopy (SEM) and the Four Point method, respectively. Mn-doped ZnO films show changes in transmittance and energy band gap when substrate temperature is increased. In the same way, electrical resistivity measurements show changes with temperature, getting a minimum value at 450 °C. The results were also compared with undoped ZnO thin films. They show that constant lattices, crystallite size and resistivity increase with Mn doping. These variations are the result of the substitution of Zn by Mn ions during the incorporation of Mn ions in the ZnO lattice. On the other hand, energy band gap values decrease when the samples were doped with Mn, due to the s–d and p–d exchange interactions.

Tungsten-oxide-based thin films were prepared by reactive DC magnetron sputtering in the presence of oxygen and nitrogen. Nitrogen contents up to 12 at.% were documented by Rutherford backscattering spectrometry and time-of-flight elastic recoil detection analysis. Optical and electrochemical measurements showed that films with up to 4 at.% of nitrogen were as transparent as undoped tungsten oxide films and displayed enhanced electrochromic properties manifested in an increase in the coloration efficiency by as much as 20%.

ZnS is a wide band gap material which was proposed as a possible candidate to replace CdS as a buffer layer in solar cells. However, the structural and optical properties are influenced by the deposition method. ZnS thin films were prepared using magnetron sputtering (MS), pulsed laser deposition (PLD), and a combined deposition technique that uses the same bulk target for sputtering and PLD at the same time, named MSPLD. The compositional, structural, and optical properties of the as-deposited and annealed films were inferred from Rutherford backscattering spectrometry, X-ray diffraction, X-ray reflectometry, Raman spectroscopy, and spectroscopic ellipsometry. PLD leads to the best stoichiometric transfer from target to substrate, MS makes fully amorphous films, whereas MSPLD facilitates obtaining the densest films. The study reveals that the band gap is only slightly influenced by the deposition method, or by annealing, which is encouraging for photovoltaic applications. However, sulphur vacancies contribute to lowering the bandgap and therefore should be controlled. Moreover, the results add valuable information towards the understanding of ZnS polymorphism. The combined MSPLD method offers several advantages such as an increased deposition rate and the possibility to tune the optical properties of the obtained thin films.

CoSe nanostructured thin films were synthesized using the chemical bath deposition method. We investigated the role of deposition time on the evolution of the nanoparticle shape, configuration and optical band gap in Cobalt selenide (CoSe) nanoparticle preparation process. Rutherford Backscattering Spectrometry was utilized, as an accurate technique, for obtaining an insight into the depth profile and the stoichiometry variation of the constituent concentration during the deposition time. The Scanning Electron Microscopy result exhibited that nanorods are formed by increasing the deposition time. Derivation Ineffective Thickness Method (DITM) was employed to determine the optical band gap energy and transitions index. The band gap energies resulted from DITM were compared with the Tauc model and it was found that there is no need for any presumption about the natural transition in DITM. The lower band gap energy of prepared thin films was achieved at the longer deposition time. The chemical structure of the azo dye Congo Red were decolorized to 90% using solar light irradiation in 60 min making the CoSe thin films a good candidate for photocatalyst.

We studied the uptake of deuterium (D) into tungsten (W) through thin films of W oxide. Two surface oxide films with thicknesses of 33 and 55 nm were thermally grown on W substrates. In the following, the oxidized samples were exposed to low-energy D (5 eV/D) from a D plasma at a sample temperature of 370 K. A defect-rich layer of self-damaged W underneath the oxide was used as a getter layer to enable the detection of D that penetrates the oxide film. Depth-resolved concentration profiles of D and oxygen (O) were obtained after the plasma exposure by nuclear reaction analysis and Rutherford backscattering spectrometry. We have found that oxygen is partially removed from the first 100 × 1019 atoms/m2 (≈ 13.5 nm) of the oxide film by the D plasma which leads to a W enrichment in the near surface region. Independent of the oxide thickness, an oxygen removal rate of (5.4 ± 0.7) × 10−4 O atoms per incident D atom was observed. Furthermore, D accumulates in the oxide film to concentrations of up to 1.3 at. %, but does not penetrate into the underlying self-damaged W. After a storage period of ten months at room temperature in vacuum, the D content in the oxide layer has decreased substantially, but still no D has penetrated into the metallic W. It is evident that surface oxide films on W effectively block the D uptake into metallic W. However, the D uptake into metallic W is not limited by the transport in the oxide film itself. D diffuses fast throughout the oxide but is stopped at the interface to the metallic W. We attribute this behavior to the difference in the heat of solution for D in W oxide and metallic W. D cannot overcome this barrier once it is thermalized to 370 K within the W oxide film.

Stopping power and energy loss straggling data of 4He+ swift ions in Bismuth thin film (Bi/Si) deposited onto silicon substrate were measured via Rutherford backscattering spectrometry (RBS) at incident energies ranging from 0.9 to 3.0 MeV. We adopted an improved experimental method based on the Kr+ ion implantation of the target Si substrate at low 40 keV energy and using the generated Kr-peak in the backscattered RBS spectra as reference to extract both the energy loss and the energy loss straggling for He+ ions crossing the Bi thin film. The obtained experimental stopping power values were found in good agreement with those generated numerically via SRIM-2013 and CasP 5.2 computer codes. They are also showed to be consistent with previously reported stopping data within the He+ ion energy region mainly below 1.5 MeV, which are thus extended them to higher incident energies. Finally, the relevance of collisional straggling values predicted by Bohr’s and Bethe-Livingston’s theories for describing the determined experimental straggling data was discussed by invoking two main additional contribution effects due to target thickness inhomogeneity and ion charge exchanges included in the Yang semi-empirical formula.

Catalytic layers on the surface of Toray Carbon Fiber Paper TGP-H-060 T and AVCarb® Carbon Fiber Paper P50 carbon carriers are formed by the ion-beam-assisted deposition of platinum and rare-earth-metal gadolinium (as an activating additive) in order to obtain electrocatalysts for the direct oxidation of ethanol and methanol for fuel cells with a polymer membrane electrolyte. The formation of the layers is carried out in the ion-beam-assisted deposition mode, in which metal deposition and mixing of the deposited layer with the substrate surface with accelerated (U = 5 kV) ions of the same metal are carried out, respectively, from the neutral fraction of the vapor and plasma of a vacuum pulsed arc discharge. The microstructure and composition of the obtained surface layers are studied using scanning electron microscopy, electron probe X‑ray spectral microanalysis, X-ray fluorescence analysis, and Rutherford backscattering spectrometry. As a result of the ionic mixing of all components, multicomponent layers containing atoms of precipitated metals and substrate elements, as well as oxygen impurities, are obtained.

We present an atomic layer deposition (ALD) process for the synthesis of tin nitride (SnNx) thin films using tetrakis(dimethylamino) tin (TDMASn, Sn(NMe2)4) and ammonia (NH3) as the precursors at low deposition temperatures (70-200 °C). This newly developed ALD scheme exhibits ideal ALD features such as self-limited film growth at 150 °C. The growth per cycle (GPC) was found to be ∼0.21 nm/cycle at 70 °C, which decreased with increasing deposition temperature. Interestingly, when the deposition temperature was between 125 and 180 °C, the GPC remained almost constant at ∼0.10 nm/cycle, which suggests an ALD temperature window, whereas upon further increasing the temperature to 200 °C, the GPC considerably decreased to ∼0.04 nm/cycle. Thermodynamic analysis via density functional theory calculations showed that the self-saturation of TDMASn would occur on an NH2-terminated surface. Moreover, it also suggests that the condensation of a molecular precursor and the desorption of surface *NH2 moieties would occur at lower and higher temperatures outside the ALD window, respectively. Thanks to the characteristics of ALD, this process could be used to conformally and uniformly deposit SnNx onto an ultranarrow dual-trench Si structure (minimum width: 15 nm; aspect ratio: ∼6.3) with ∼100% step coverage. Several analysis tools such as transmission electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy, Rutherford backscattering spectrometry, and secondary-ion mass spectrometry were used to characterize the film properties under different deposition conditions. XRD showed that a hexagonal SnN phase was obtained at a relatively low deposition temperature (100-150 °C), whereas cubic Sn3N4 was formed at a higher deposition temperature (175-200 °C). The stoichiometry of these thermally grown ALD-SnNx films (Sn-to-N ratio) deposited at 150 °C was determined to be ∼1:0.93 with negligible impurities. The optoelectronic properties of the SnNx films, such as the band gap, wavelength-dependent refractive index, extinction coefficient, carrier concentration, and mobility, were further evaluated via spectroscopic ellipsometry analysis. Finally, ALD-SnNx-coated Ni-foam (NF) and hollow carbon nanofibers were successfully used as free-standing electrodes in electrochemical supercapacitors and in Li-ion batteries, which showed a higher charge-storage time (about eight times greater than that of the uncoated NF) and a specific capacity of ∼520 mAh/g after 100 cycles at 0.1 A/g, respectively. This enhanced performance might be due to the uniform coverage of these substrates by ALD-SnNx, which ensures good electric contact and mechanical stability during electrochemical reactions.

The magnetic properties of MgO thin films were discussed as an interplay among the oxygen vacancies, Mg2+ ion coordination and structural order deposited using radio frequency (RF) sputtering method by varying substrate temperature and deposition power followed by in-situ annealing. Rutherford backscattering spectrometry (RBS) and high resolution transmission electron microscopic (HRTEM) performed for these films showed decrease of film thickness with increase of substrate temperature. Films are thicker for higher sputtering powers at corresponding substrate temperatures. Spectral features in Mg K-edge near edge X-ray absorption fine structure (NEXAFS) spectra are characteristics of MgO for both sputtering powers at substrate temperature of room temperature (RT) and 350 °C. O K-edge NEXAFS spectra exhibited onset of oxygen vacancies as inferred from pre-edge region. Magnetization versus applied magnetic field curves for these films showed onset of do ferromagnetism. This behavior ceased with increase of substrate temperature, however, become dominant with increase of sputtering power. Magnetic behavior was dominant for the films which had slightly distorted Mg2+ ion co-ordination. The existence of oxygen vacancies was not observed to be consistent with magnetization. Thus, this study envisaged the role of Mg2+ ion coordination, long range structural order and oxygen vacancies in order to determine magnetism in these systems.

Porous silicon oxide thin films were deposited by combustion chemical vapour deposition (CCVD). Depending on the process parameters applied, the layer thickness ranged from 18 to 165 nm, as obtained by profilometry and spectral ellipsometry (SE). The layer morphology was investigated by scanning electron microscopy (STEM) and atomic force microscopy (AFM) revealing roughnesses of the respective films between 0.1 and 42.4 nm. The porosity of the films was determined using weighing, SE, and Rutherford backscattering spectrometry (RBS) with all methods giving similar values. The porosity varied between 21 and 93%. These high porosities can be an effect of voids resulting from pores and roughness. The investigations revealed an open porosity. The received porosities were correlated with FTIR signal. The FTIR signal strength per unit volume Ψ correlates linearly with the porosity. This result can be used as a calibration curve. Thus, the porosity of an unknown silicon oxide layer can be deduced from the measured FTIR signal and the layer thickness. All methods applied here yield a consistent description of the layer properties.

Tungsten nitride (WNx) thin films were deposited on SiO2 substrates by atomic layer deposition (ALD) using a fluorine- free tungsten metal-organic precursor of tris(3-hexyne) tungsten carbonyl, W(CO)(CH3CH2C ≡ CCH2CH3)3 and NH3 plasma as a reactant at a deposition temperature of 250 °C. Important ALD characteristics, such as self-limiting growth and linear dependency of the film growth on the number of ALD cycles, were obtained with a growth rate of 0.045 nm/cycle. The minimum film resistivity of around ~2800 μΩcm (thickness: ~ 13.3 nm) was stable after 3 days air-exposure, indicating the high stability of these WNx films. Rutherford backscattering spectrometry showed that the N-rich WNx thin films (N/W ratio: ~ 1.56) were deposited with negligible impurities of C and O. Both X-ray diffractometry and transmission electron microscopy analysis showed that ALD-WNx films formed a polycrystalline cubic WN phase with an average grainsize of ~ 6 nm. From scanning Kelvin probe analysis, its work function was determined as 4.79 eV. Detail investigations were carried out after post-annealing of the as-deposited films and formation of metallic-W with significantly reduced sheet resistance was observed upon annealing at and beyond 700 °C. Finally, the ultrathin (~5 nm) ALD-grown WNx film effectively prevented diffusion of Cu even up to 550 °C, promising it as an efficient diffusion barrier material for the Cu interconnect.

The electronic excitation and modification in the properties of the target material occur due to the kinetic energy loss of incident ions mainly through the inelastic collision with atomic electrons in the process of electronic energy stopping. Nanocomposite tin oxide (SnO2) and titanium dioxide (TiO2) thin film were grown on silicon and ITO substrates using RF magnetron-sputtering process. These thin films were irradiated by 120 MeV Au9+ Swift Heavy Ion (SHI) beam with varying fluence from 5 × 1011 ions cm−2 to 2 × 1013 ions cm−2 to induce modifications in thin films by dense electronic excitation. Surface morphology and depth profile of craters (approx. 85 nm) have been characterized by multimode atomic force microscopy (AFM). Grain mapping of AFM images provided the variation in grain size in the range of 72–279 nm and RMS roughness increased (4.01–23.6 nm) with increasing the ion fluence. Scanning Electron Microscopy (SEM) was also carried out to confirm the formation of craters in the irradiated film. X-ray diffraction (XRD) technique has been used for the structural analysis of virgin and irradiated thin films. XRD patterns established the formation of film in mixed (rutile and gamma) phase. Further, the crystallite size was evaluated using the Debye–Scherrer and Williamson–Hall method. It was found that crystallite size lie in the range of 36–54 nm which increased for the lower fluence and then decreased for higher fluence. The ion irradiation-induced strain has been explained by Thermal spike and Coulomb explosion model. UV–Vis study showed that the optical band gap reduced from 3.87 to 3.72 eV with increasing the ion fluence which can be ascribed to the formation of intermediate states and free radicals between the valance and band conduction band. Rutherford Backscattering Spectrometry (RBS) ensured that the film thickness decreased from 210 to 183 nm with increasing the ion fluence. The simulation of the RBS spectra provides the elemental composition of Sn (0.37), Ti (0.65) and O (0.85) in SnO2 and TiO2 nanocomposite thin films.

Wide band gap materials like ZnO are being studied due to their potential applications in various devices. Here, in this work, ZnO thin films have been prepared using magnetron sputtering technique. Scanning Electron Microscopy (SEM) studies show rough surface. Only partial coverage is obtained for lower thickness and the coverage increases to maximum at higher thicknesses. Rutherford backscattering spectrometry results show the interfacial diffusion at Si–ZnO interface. High Resolution Transmission Electron Microscopy (HRTEM) and Selected Area Diffraction (SAD) studies show the polycrystalline nature of the films. As the thickness increases, number of defects also increases. Presence of Moire fringes and planar defects have been discussed using Fourier filtered HRTEM images and their corresponding FFTs.

We have evaluated possibilities of using the method of Rutherford backscattering spectrometry (RBS) for depth profiling of multilayer thin-film structures containing nanodmensional layers of elements with close atomic masses. It is established that RBS measurements can ensure high precision determination of the composition of these multilayer structures, total film thickness, and thicknesses of separate layers. This ability can be used for the input quality control of multilayer structures used in micro- and nanotechnologies.

The interface of Ni-NiO thin films was developed by thermal evaporation of nickel and subsequent annealing in oxygen atmosphere at 400 °C at varying duration of time. The evolution of layer thicknesses with annealing time was studied using rutherford backscattering spectrometry. The structural characterization showed grain growth stagnation for Ni at higher duration of annealing. The Ni phase had more crystallinity compared to the NiO phase. The surface was studied using atomic force microscope. The magnetic domains were also imaged. Magnetic stripe domain patterns were observed for selected films. Variation in saturation magnetisation and coercivity with annealing time was observed. The observation of weak exchange bias shows the importance of antiferromagnetic phase in determining the exchange bias properties. Thermal annealing of Ni films caused a competition among oxidation and grain growth.

Titanium dioxide (TiO2) thin films were grown on Silicon and glass substrates at room temperature by RF sputtering deposition technique. All deposited thin films were irradiated by 800 keV Kr5+ low energy ion beam with varying ion fluence from 1E15 ions/cm2 to 1E17 ions/cm2. The decreases in crystallite size from 42.09 nm to 27.36 nm (by Scherrer's formula) with increased in ion fluence were observedusing X-ray Diffraction (XRD) technique. The orientation of the different planes was observed but the plane (112) confirmed the preferred orientation as determined by the texture coefficient using XRD patterns. The surface morphology of the samples was studied by Atomic Force Microscopy (AFM) technique in the tapping mode and the Root Mean Square (RMS) roughness (Rq) was found to be increased from 0.739 nm to 3.20 nm with increases the ion fluence. The energy bandgap was found to be increased from 4.06 eV to 4.30 eV by increased in ion fluence due to electron confinement at nano-scale and also observed Urbach energy and optical conductivity by UV–Visible spectroscopy. The Urbach energy of thin films was observed to increased with increasing the ion fluence. The photoluminescence (PL) spectra confirmed the enhancement in the recombination of electron hole pair with increases the oxygen vacancies by increases the ion fluence. The peak at 382 nm was observed at higher fluence of 7E15 ions/cm2, 3E16 ions/cm2 and 1E17 ions/cm2. In the Raman studies, all six Raman modes at their positions for anatase phase of TiO2 thin films were successfully observed. The thickness of thin films was observed 268 nm and elemental composition of titanium and oxygen in all thin films were confirmed in the ratio of 1:2 by using Rutherford Backscattering Spectrometry (RBS). The electrical properties were studied by measuring the variation of current (I) with respect to the applied potential (V) at room temperature and the conductivity of the irradiated thin films was decreased with increases of ion fluence.

Silicon (Si) has been the most widely used semiconductor for decades, playing an important role in the field of electronics, energy conversion and energy storage. Because of their unique morphological energy band characteristics, Si nanostructures exhibit superior performance in many applications in comparison with their bulk counterparts. In this study, the effects of thermal annealing on elemental composition and morphological properties of palladium metal thin films grown on c-Si substrates were investigated. Palladium (Pd) thin films of different thicknesses were deposited on Si (1 0 0) with and without native oxide layers by electron beam evaporation and annealed in vacuum at 600 °C for two hours. Scanning electron microscopy (SEM) studies have shown that the surface morphology showed an effective dewetting in individual droplets and islands which further coalesce into bigger islands. Rutherford backscattering spectrometry (RBS) and electrical measurements analyses revealed the diffusion of the Si substrate into the Pd layer during annealing. This contribution will discuss the effects of the metal layer thickness as well as the native oxide on the metal thin films.

ZnSxTe1-x thin films were prepared by sulfur implantation into ZnTe grown by molecular beam epitaxy and subsequent pulsed laser melting. The chemical composition and layer thickness of the ZnSxTe1-x layer have been analyzed based on Rutherford backscattering spectrometry. Raman and photoluminescence spectroscopies were employed to reveal the optical properties of the ZnSxTe1-x layer. Raman spectra exhibit a redshift of the longitudinal optical photon modes with increasing sulfur concentration. The room temperature photoluminescence measurement indicates the appearance of the sulfur induced energy state in the bandgap.

Ion irradiation is known to create structural disorder and crystallization improvement in the material. In the present study, focus is on the effect of high energy ion beam irradiation on the optical, surface morphological and structural properties of ZrO2 thin films of 200 nm grown on Si and glass substrate by RF sputtering technique. The prepared thin films were annealed at 600 °C and irradiated with swift heavy ions (SHI) of 120 MeV Ti9+ ion beam with varied fluences ranging from 5E11 to 2E13 ions/cm2. SRIM simulation reveals that the electronic energy losses (Se) dominate over the nuclear energy losses (Sn) and the projected range of the Ti ions was found to be 13.64 μm. Optical properties were studied by using UV-Vis and Photoluminescence (PL) spectroscopy. The transmittance of the ZrO2 samples lies in the range of (46–79%) and the Tauc's plot was used to calculate the optical band gap. PL spectroscopy demonstrates the emission spectrum using the excitation wavelength of 310 nm. The influence of SHI irradiation on the surface morphology of ZrO2 thin films was examined by Atomic Force Microscopy (AFM) and Field Emission Scanning Electron Microscopy (FESEM). The sectional analysis of AFM images reveals that the grain size decreases with increasing the ion fluences and lies in the range of 51-29 nm. The structural analysis of pristine and irradiated samples was done by using X-ray diffraction (XRD) technique. The crystallite size increases for the lower fluence up to 1E12 ions/cm2 and decreases at higher fluence due to the development of fragmentation by the effect of SHI irradiation. XRD patterns were used to calculate strain, stress, dislocation density and texture coefficient of the ZrO2 samples. Rutherford Backscattering Spectrometry (RBS) ensures the presence of Zr and O elements with the atomic fraction of 1: 2 and thickness (200 nm) of the samples was confirmed by simulating the RBS spectrum. The modifications induced in the properties of the ZrO2 thin films were mainly due to the electronic energy losses through the inelastic collision in the target material.

In the present work, we show the preparation of (In,Ga,Mn)As films with different Ga concentration by Mn ion implantation and pulsed laser melting. All films are confirmed to be well recrystallized by Rutherford backscattering spectrometry/channeling and to be ferromagnetic by magnetometry measurements, respectively. Their Curie temperatures depend on the Ga concentration. Our results show the perspective of ion implantation in the preparation of different III-Mn-V quaternary alloys as new members of diluted ferromagnetic semiconductors.

The results of depth profiling a four layered Si–O−Al thin film with different concentrations of elements in the layers are presented. Secondary-ion mass spectrometry (SIMS) and Rutherford backscattering (RBS) facilities are used to obtain the depth distributions of the element densities in the film. The data of analysis by the SIMS method are used as the initial concentration profiles in processing the Rutherford backscattering spectra using the SIMNRA program. As a result, a model film structure is constructed that describes the spectra of Rutherford backscattering obtained under various experimental measurement conditions, refines the results of analysis by the SIMS method and allows quantitative distributions with respect to the depth of the element concentration and the film density to be obtained.

Rutherford backscattering spectrometry, X-ray photoelectron and X-ray energy dispersive spectroscopies were employed to analyse Bi incorporation into ZnO:Al and ZnO:Ga transparent and electrically conductive thin films deposited by d.c. magnetron sputtering, with thickness in the range of 300–400 nm. Sputtering was performed in an argon atmosphere from two targets in confocal geometry being one composed of either ZnO:Al2O3 or ZnO:Ga2O3 composites and the other a Bi metal target. The content of bismuth dopant in the ZnO matrix was controlled by the respective target current density (JBi) in order to attain a high optical transparency (>80%) in the visible region. For ZnO:Al,Bi films Bi content varied from 0.1 to a maximum of 1.5 at.% when varying JBi from 0.06 to 0.26 mA cm−2. However, for ZnO:Ga,Bi films, deposited in similar conditions, Bi reached a maximum overall layer content of 2.4 at.%, with a surface enrichment content that varied from 1.3 to 8.8 at.%. It was also observed that the Bi content in the topmost layers of the films is slightly depleted due to thermal evaporation upon thermal annealing in vacuum at 350 °C. It is envisaged applications for these films as transparent photoelectrodes and thermoelectric materials., Fundação para a Ciência e a Tecnologia (FCT, Portugal)/PIDDAC through the Strategic Funds project reference UID/FIS/04650/2013. Filipe Correia is grateful to the Fundação para a Ciência e a Tecnologia for the Ph.D. Grant SFRH/BD/111720/2015. Paulo Salvador is grateful to the Project WinPSC - POCI-01-0247-FEDER-017796, for the research grant, co-funded by the European Regional Development Fund (ERDF), through the Operational Programme for Competitiveness and Internationalisation (COMPETE 2020), under the PORTUGAL 2020 Partnership Agreement. Joana Ribeiro is grateful to University of Minho for the Grant UMINHO/BI/66/2017

Bipolar Pulse High Power Impulse Magnetron Sputtering (BP-HiPIMS) was investigated and used in this work to control the ion bombardment process of growing thin films and to improve their structure and properties. Energy-resolving mass spectroscopy was used to investigate the effect of reverse target voltage on the ion energies and fluxes during BP-HiPIMS of a high-purity copper target, in argon gas. It was found that the reverse target voltage provides a wide range of ion energies and fluxes incident to the growing film, which, in turn, produce a wide variety of effects during the deposition process, improving the adhesion strength and influencing both surface and bulk properties. Fast ICCD imaging was used to investigate both HiPIMS and BP-HiPIMS plasma dynamics. The temporal and spatial distributions of plasma potential measurements were performed in order to explain the mechanisms for accelerating the ions. The topological, structural and mechanical properties of the deposited coatings were investigated using atomic force microscopy (AFM), X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS), thermal desorption spectroscopy (TDS), scanning electron microscopy (SEM), nanoindentation and scratch tests. The obtained results indicate an energy-enhanced deposition process during BP-HiPIMS, the deposited films being characterized by smooth surfaces, dense microstructure, small inert gas inclusions, high elastic strain to failure, scratch resistance and good adhesion to the substrate. These improvements in the films' structure and properties may be attributed to the intense and energetic ion bombardment taking place during the deposition process. During BP-HiPIMS operation, there is no net increase in the deposition rate as compared to the monopolar regime due to the re-sputtering process.

The calibrated and controlled swift heavy ions (SHI) beam irradiation generate defects which can cause modifications in various properties of the materials such as structural, optical, magnetic, morphological, and chemical etc. The passage of ion through the target material causes the nuclear energy losses ( S n ) and electronic energy losses ( S e ). The S e dominates over S n in SHI irradiation. In the present study, ZrO2 thin films were grown on silicon and glass substrate by using RF sputtering deposition technique. For the purpose of modifications induced by swift heavy ions, these films were irradiated by a 120 MeV S9+ ion beam of 1 pnA current, with varying ion fluences from 5E12 to 1E13 ions/cm2, using the tandem accelerator at the Inter University Accelerator Center (IUAC), New Delhi, India. The X-ray diffraction (XRD) patterns confirmed the formation of monoclinic and tetragonal phases and it was observed that XRD peaks intensity increased up to the fluence of 5E12 ions/cm2 followed by opposite behavior at higher fluences. Atomic force microscope (AFM) study revealed the increased surface roughness after SHI irradiation. In addition to it, the formation of electronic transition states in optical band gap region and enhancement of absorption edge was observed from UV-visible spectroscopy (UV-Vis) results due to which direct band gap energy value decreased from those of un-irradiated samples. Photoluminescence (PL) broad emission spectra were determined using the excitation wavelength at 290 nm with the prominent peak at 415 nm which can be ascribed to Zr vacancies due to band edge emission as a result of free-exciton recombination. Rutherford backscattering spectrometry (RBS) technique was used for depth profiling and elemental composition in zirconia thin films. The expected role of electronic energy loss during ion irradiation is to modify the properties of the material has been discussed.

The microstructure, texture and optical properties of Sn doped Ge2Sb2Te5 thin films were investigated in this work. The correlation between grain orientation and optical reflectivity of Sn doped Ge2Sb2Te5 thin films has been obtained. Thin films with different compositions were deposited on SiO2/Si (100) wafer using magnetron sputtering method. Both the composition and thickness of thin films were determined using Rutherford backscattering spectrometry (RBS). It appears that face-centered-cubic (fcc) and close-packed-hexagonal (hcp) structure coexisted in Sn doped Ge2Sb2Te5 thin films. Rietveld structure refinement indicates that the lattice constant of the fcc structure increased with increasing Sn content, while the lattice constant of the hcp structure remains nearly unchanged. Sn doping also leads to the appearance of defects and disordered local arrangement in Ge2Sb2Te5 films. Furthermore, the crystalline optical reflectivity of Sn doped Ge2Sb2Te5 thin films increased, which is attributed to texture formation. The texture component of the hcp structure Ge2Sb2Te5 thin films transformed from cylindrical {01-10} to basal {0001} during the addition of Sn atoms. Accordingly, we proposed a model of texture and optical reflectivity, that is, the basal texture facilitates the high crystalline optical reflectivity of Ge2Sb2Te5 thin films thanks to the six-fold rotational symmetry in the hcp structure.

Rutherford backscattering spectrometry (RBS) is an analysis method to quantify reference free the atomic areal density of a thin film, in particular sensitive to those cases where the elements of the film are heavier than the substrate. The ultimate sensitivity is determined by the ratio between the signal intensity from the thin film and the background signal originating from e.g. pulse pile-up events related to the scattering from the substrate atoms or dark noise intrinsic to the detector. We demonstrate that the sensitivity of RBS can be improved by reducing the pulse pile-up and dark noise background through the implementation of a magnet sector and a silicon strip detector as combined double energy dispersive analyzer. A limit-of-detection of 3∙1011 Ru/cm2 on Si is achieved.

The layer composition and crystallinity of single-layer Fe 3 O 4 (001) and bi-layer Fe 3 O 4 /Fe(001) thin films grown epitaxially on MgO(001) substrates have been investigated by Rutherford backscattering spectrometry (RBS), channeling experiments (RBS-C) and X-ray reflectometry (XRR). Four thin films with similar film layer structure but different layer thickness have been irradiated by 1 MeV Ar + or 1 MeV Kr + ion beam with ion fluences in the range of ~0.8–20.7 × 10 16 ions/cm 2 for a detail underlining the ion mixing effect and its influence on the layer stability. The ion fluence of 4.4 × 10 16 Ar + /cm 2 and 0.8 × 10 16 Kr + /cm 2 was enough to change the stoichiometry of the Fe 3 O 4 layer in the single-layer Fe 3 O 4 films, while the stoichiometric Fe 3 O 4 layer on the surface of bi-layer films were well preserved at a much higher Ar + and Kr + ion fluence (20.7 × 10 16 Ar + /cm 2 and 2.5 × 10 16 Kr + /cm 2 ), despite that such ion fluencies could induce a complete oxidization of the buffer Fe layer. The stability of the Fe 3 O 4 layer and the bilayer structure of the film after Ar + ion irradiations at an ion fluence about 10 times larger than that of Kr + ion indicate a high potential for practical applications of the bilayer magnetite films in an argon atmosphere.

In the present study, Zirconium oxide thin films of 150 nm were grown by RF magnetron sputtering at room temperature. The prepared thin films annealed at 550 °C and irradiated with SHI of 120 MeV Au9+ ions by varying ion fluence between 1 × 1011 to 1 × 1013 ions/cm2. The modifications induced by SHI irradiation in structural, surface morphological, optical and chemical properties of the thin films have been characterized by X-ray diffraction (XRD), Atomic Force Microscope (AFM), UV–Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), Photoluminescence (PL) and Rutherford backscattering (RBS). XRD result shows the formation of monoclinic and tetragonal phase with the change in the intensity of the peak is observed due to SHI irradiation. AFM measurements ensure that the grain size lies in the range of 33–46 nm and root mean square roughness increases up to a fluence of 5 × 1011 ions/cm2 then decrease for the higher fluence. Photoluminescence (PL) emission peaks were obtained at 456, 488 and 516 nm when the pristine and irradiated ZrO2 thin films are excited with 300 nm light. The obtained peak in Rutherford Backscattering Spectrometry (RBS) confirms the presence of Zr and O atoms in the samples.