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In this work, we have successfully prepared the nano-coral to be intact with the mesoporous of Sn-HfO2 thin films through the (jet nebulizer spray pyrolysis) JNSP technique from different Sn (5, 10, 15 Wt.%) to improve the MIS Schottky diode Al/Sn-HfO2/n-Si. To achieve the phase transformations (monoclinic to orthorhombic) in pure hafnium oxide thin films, we have added the Sn ions as the composite at optimized temperature 600 °C. The XRD characteristic used to determine the structural parameters such as the phase, grain size for pure HfO2, and composite Sn-HfO2 films. The mesoporous with irregularly shaped balls and nano coral-like morphology have been observed through FESEM images. The absorption coefficients and bandgap energy have been determined from the UV Vis spectrum. The EDAX elementary analysis has confirmed the presence of Sn, Hf, O elements in each film. The XPS spectrum has confirmed Sn's presence and binding peak with a spin-orbit on the films' surface. I-V curves of forward and reverse bias determine the barrier height, ideality factor, and saturation currents from the thermionic emission theory. All the Al/Sn@HfO2/n-Si diode parameters are strongly improved after the incorporation of Sn ions. [ABSTRACT FROM AUTHOR]

In this work, pure and Mn-doped nickel ferrite (Ni1-xMnxFe2O4, x = 0, 3, 6, 9, and 12 wt%) thin films were prepared using facile nebulizer spray pyrolysis technique. The effect of Mn concentration on the structural, optical, and magnetic properties was studied. The XRD pattern confirms the cubic spinel structure of Ni1-xMnxFe2O4 thin films and reveals the preferred orientation along the (311) direction for each film. Moreover, the average crystallite size (D) is found to increase from 13 to 30 nm with increasing Mn concentration. The FESEM micrographs exhibit randomly arranged plate-like and rice-like grains. The elements such as Mn, Ni, Fe, and O are confirmed by the EDX analysis. The optical band gap energy (Eg) varies between 2.90 and 3.60 eV. The Ni1-xMnxFe2O4 film prepared with 3 wt% of Mn exhibits superior ferrimagnetic behavior with the highest value of ηB (57.31) due to the high crystallinity, packing density, and smooth surface of the film. The present work shows that the facile nebulizer spray pyrolysis technique can produce high-quality Ni1-xMnxFe2O4 thin films with good magnetic properties. [ABSTRACT FROM AUTHOR]

Nebulizer spray pyrolysis (NSP) technique has been successfully employed for the deposition of well-dispersed highly homogeneous spindle-shaped yttrium-doped cerium oxide (YDC) films. Optical studies revealed a decreasing trend of transmittance with the increasing Y doping percentage up to 20% and then increase in transmittance at 25% either due to the increased crystal defect induced photon scattering or the increased metal-to-oxygen ratio at higher Y doping. PL spectra showed four distinct broad peaks at 3.34 eV (near-band-edge emission (NBE) at UV), and 3.14, 2.91 and 2.65 eV (deep-level emission (DLE) in the visible spectra at violet, blue and green, respectively) corresponding to the wavelengths 365, 394, 425 and 465 nm, respectively. XRD studies confirmed the polycrystalline cubic fluorite single-phase structures preferentially orientated along (200) and (111) reflections without any impurity peaks. SEM images showed that YDC films are grown with small granules containing spherical-shaped particles having many cracks and patches. The average width of tiny granules inside the well-aligned taper-like structures is found within the order of 138 nm. The observed changes in the rectification ratio of p-Si/n-YDC diode with voltage are allied to the corresponding changes in both series (Rs) and shunt resistances (Rsh) of the heterojunction. The transient photocurrent characteristics indicate that the prepared heterostructure is highly stable and has quick response, which advocates the use of prepared heterojunction device in UV detector and white light photodetector applications. [ABSTRACT FROM AUTHOR]

Monoclinic WO3-nanoplate arrays have been effectively deposited via simple jet nebulizer spray pyrolysis technique at an optimized substrate temperature of 400 °C. These WO3-nanoplate arrays were used as an insulating layer in the metal–insulator–semiconductor (MIS) structure based Schottky barrier diodes. The effect of WO3 mol concentration during the deposition process was systematically interpreted with respect to the structural, morphological, optical and electrical properties of WO3-nanoplate array films. XRD pattern exposed the polycrystalline nature of the prepared films with a monoclinic phase. At higher concentration of 0.25 M WO3-nanoplates were firmly interconnected together and has been analyzed by a FE-SEM. From UV–Vis spectroscopy, the band gap values of the WO3 were found to vary from 3.2 to 3.4 eV with mole concentrations. DC electrical study recorded a steep increase in the electrical conductivity for the film prepared with 0.2 M of WO3. Notably, all the diodes exhibited positive photoresponse under illumination. Particularly, the MIS diode fabricated with 0.2 M revealed higher photoresponsivity and sensitivity of 960.85% and 33.40 mA W−1 respectively. [ABSTRACT FROM AUTHOR]

Tungsten disulfide (WS2) thin films were deposited on the glass substrate by varying its temperature from 350 to 500 °C using jet nebulizer spray pyrolysis (JNSP) technique. The WS2 thin films were characterized through various techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy dispersive X-ray analysis (EDX), UV-Visible spectroscopy (UV), photoluminescence (PL), Hall measurements and current-voltage (I-V) characteristics. XRD pattern revealed that the prepared WS2 films are polycrystalline in nature with rhombohedral and hexagonal crystal structures. The average crystallite size of WS2 thin films changed from 52.23 to 47.40 nm. SEM images showed the uniform grain size, which is agglomerated at the higher substrate temperature. The presence of elements like W and S was confirmed through EDX spectrum. From UV analysis, the minimum optical band gap and maximum absorption was obtained for the film deposited at 450 °C. The WS2 thin films exhibited an n-type semiconductor nature with the carrier concentration of 1014 cm−3, which was demonstrated through hall measurements. Also, the electrical resistivity of the WS2 films varied from 3.26 × 105 to 1.59 × 107 Ω cm. The p-Si/n-WS2 junction diode was fabricated with various substrate temperature of (350-500 °C). Junction diode parameters like ideality factor (n), barrier height (ϕB) and reverse saturation current (Io) values were calculated and interpreted based on the thermionic emission theory model. [ABSTRACT FROM AUTHOR]

In this work, two different structure of Cu/Sr-WO 3 /p-Si metal-insulator-semiconductor (MIS) and Cu/Sr-WO 3 /FTO metal-insulator-metal (MIM) Schottky barrier diodes (SBDs) fabricated with an insulating layer of pure tungsten trioxide (WO 3 ) and Sr-WO 3 thin films have been reported. The Sr-WO 3 layer was coated separately, with different concentrations (0, 4, 8 and 12 wt %) of strontium (Sr) via jet nebulizer spray pyrolysis technique (JNSP) on the p-type silica wafer (p-Si) and fluorine doped tin oxide (FTO) substrates which are been optimized at 400 °C. The XRD analysis reveals the multiphase crystalline structures for 12 wt % of Sr-WO 3 film with higher average crystallite size. FE-SEM images show the randomly oriented sub-microsized slab and seashell like structures. Higher surface roughness with improved grain size for 12 wt % of Sr-WO 3 film. The presence of W, O and Sr atoms was confirmed by EDX spectra. In optical studies, Maximum absorption with minimum optical band gap was observed for 12 wt % of Sr-WO 3 composite film. There was a linear increase in the electrical conductivity of the films with higher wt. % of Sr. Evidently the activation energy decreased with Sr concentration which is in accordance with the bandgap values. The fitting results of the measured I-V, reveal that MIS (SBDs) under illumination condition have minimum ideality factor (n = 2.39) and maximum barrier height (Φ b  = 0.57) values for higher concentration (12 wt %) of Sr film compared to MIM SBDs. [ABSTRACT FROM AUTHOR]

Metal–insulator–semiconductor (MIS) structure of Cu/Zr–WOx/p-Si Schottky diodes with different concentrations (0, 4 and 8 wt%) of Zr content were fabricated. The interfacial layer of zirconium–tungsten oxide (Zr–WOx) film was grown on p-type silicon (p-Si) wafer using jet nebulizer spray pyrolysis (JNSP) technique at the substrate temperature of 400 °C. After that, the Cu electrode was coated on the Zr–WOx film via vacuum deposition method. The multiphase (orthorhombic and cubic) crystal structures of Zr–WOx were revealed by X-ray diffraction (XRD) pattern. The surface morphological analysis using scanning electron microscope (SEM) showed the dissimilar structures of surface and energy dispersive X-ray diffraction (EDX) confirmed the presence of W, Zr and O atoms. Using UV–Visible (UV–Vis) and DC elecrical (I–V) analysis, the minimum band gap energy and average conductivity were obtained for higher concentration (8 wt%) of Zr content. The minimum barrier height (ΦB) and minimum ideality factor (n) values were attained for 4 wt% of Cu/Zr–WOx/p-Si Schottky barrier diode (SBD) under illumination condition. [ABSTRACT FROM AUTHOR]

[Display omitted] • A nanostructured Zn@HfO 2 thin films were through the JNSP technique. • The mesoporous with irregular balls intact nanorods-like structured morphology was observed by FESEM images. • The band gap values are receded continuously after doping. • We have fabricated Al/Zn@HfO 2 /n-Si diode for various Zn concentration. • A minimum ideality factor was obtained for 15 wt% of MIS diode. In this work, we have prepared the nanorods are intact with mesoporous of Zn@HfO 2 thin films through the JNSP technique with different concentrations of Zn (5,10,15 Wt%) to improve the MIS Schottky diode Al/Zn-HfO 2 /n-Si performance. The XRD was used to determine the structural parameters such as the phase and grain size for both pure HfO 2 and Zn@HfO 2 composite films. The mesoporous with irregular balls and nano rod-like morphology have been observed through FESEM images. The absorption coefficients and bandgap energy were calculated from the UV–vis spectrum. The EDAX analysis has confirmed that the Zn, Hf and O percentages in both films. The XPS spectrum has confirmed Zn's presence and binding natural with a spin-orbit splitting on the films' surface. By the thermionic emission theory, I-V curves of forward and reverse bias are used to determine the barrier height, ideality factor and saturation currents. All the Al/Zn@HfO 2 /n-Si diode parameters are strongly improved after the incorporation of Zn ions. [ABSTRACT FROM AUTHOR]