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The present research explores the fabrication of a metal insulator semiconductor Schottky barrier diode (SBD) with rare earth metal oxide (Yb2O3) thin films as insulators that are effectively developed on a large scale using the low-cost jet nebulizer spray pyrolysis technique (JNSP). The Yb2O3 thin films are deposited at various substrate temperatures (350 °C–550 °C) to ascertain its influence on the characteristic properties of the material. The structural, morphological and opto-electrical properties are investigated using various characterization techniques. Here, X-ray diffraction (XRD) analysis revealed the single crystalline cubic crystal structure of Yb2O3 thin films. Field emission scanning electron microscope (FESEM) images show the presence of uniformly distributed cage and globular like structures spread over the entire surface of the Yb2O3 films. The elemental composition study demonstrates the presence of Yb and O. The optical direct energy band gap of Yb2O3 thin films have been analyzed through UV-Visible spectra. Current – voltage measurements were analyzed in dark and light conditions for the Al/Yb2O3/p-Si structured Schottky barrier diodes (SBDs) which are fabricated with interfacial layers at different substrate temperatures. Further, the functionality of the SBDs was tested at different temperatures ranging from 30 °C to 150 °C. The experimental results of all SBDs indicate a linear reduction in the ideality factor (n) up to 2.537 and 2.059 with a slight increase in the effective barrier height (ФB) of 0.789 eV& 0.638 in dark and light conditions, respectively. The SBD fabricated at 550 °C recorded good performance, which will be suitable for thermal dependent electronic device applications. [ABSTRACT FROM AUTHOR]

Abstract Here, we fabricated highly sensitive metal-insulator-semiconductor (MIS) type diodes with positive photo-response by introducing a polycrystalline Ce-WO 3 composite thin films as an interfacial layer (IL) between the metal (Cu) and semiconductor (p-Si). Ce-WO 3 films were successfully grown on a quartz substrate through JNSP technique with 0, 4, 8 and 12 wt% of Ce on an optimized substrate temperature of 400 °C. Polycrystalline Ce-WO 3 films with mono-phase of monoclinic crystal structure were observed in XRD analysis, in which the mean crystallite size of the films were found to dwindle and their corresponding lattice parameters improved with Ce concentration. Randomly arranged rectangular shaped nanoplate-like surface morphology was observed through FESEM. From AFM study, the observed surface roughness of the films was found to be varying between 183 and 116 nm. Incorporation of Ce atoms in WO 3 matrix facilitated better optical absorption and minimized E g values which was studied using UV–vis spectrum. Current-voltage (I-V) characteristics exhibit highest σ dc with low ρ and E a values for higher concentration of Ce. For Cu/Ce-WO 3 /p-Si type diodes, as the light intensity of the diodes increased from 0 to 130 mW/cm2 their corresponding ideality factor (n) was found to decrease. Moreover, significant photodiode parameters like P S , R, QE (%) and D* enhanced with Ce and in particular the MIS diode fabricated with its 12 wt% showed better results in which a remarkable responsivity of 20.61 mA/W was recorded. Graphical abstract Unlabelled Image Highlights • Ultra-fast photoresponse and high sensitive based MIS type diodes have been fabricated by a simple JNSP technique. • The nanoplate-like surface morphology was observed through FESEM analysis. • The MIS diode fabricated with 12 wt% showed high responsivity of 20.61 mA/W. • High photosensitivity of P S = 17,509.62% and a maximum quantum efficiency of QE = 9.72% were obtained at 130 mW/cm2. • The fabricated Cu/Ce-WO 3 /p-Si type diode will be ideal for UV photodetector application. [ABSTRACT FROM AUTHOR]

• Undoped and Sn doped Co 3 O 4 thin films were prepared by JNSP method. • Spherical-like grains are observed from the FE-SEM images. • The optical band gap of Co 3 O 4 film is noticed to be increased after adding Sn ions. • We have fabricated an undoped and Sn doped p-Co 3 O 4 /n-Si junction diode for various concentrations. • We observed that the p-Sn@Co 3 O 4 /n-Si diodes are highly sensitive and appropriate for photodetection applications. [Display omitted] In this work, we have prepared Co 3 O 4 thin films for different doping level including 0, 2, 4, and 6 wt% by JNSP method and analyzed their structural, morphological, optical, and electrical properties by XRD, FE-SEM, EDX, UV-Vis, and current-voltage (I-V) characteristics. The XRD profiles confirm the cubic crystal structures of Sn doped Co 3 O 4 films. Spherical-like grains are observed from the FE-SEM images and were suppressed due to Sn doping. Also, the elements like Sn, Co, and O were confirmed by EDX analysis. The optical band gap of Co 3 O 4 film is noticed to be increased after adding Sn ions, which has been studied through UV-Vis spectroscopy. Most importantly, we have fabricated an undoped and Sn doped p-Co 3 O 4 /n-Si junction diode for various concentrations. The determined ideality factor of the p-Sn doped Co 3 O 4 /n-Si diodes were reduced for both under dark and light conditions. In addition, the calculated responsivity, quantum efficiency, and specific detectivity of the diodes were enhanced with forwarded voltage. The p-Sn@Co 3 O 4 /n-Si diode fabricated with 2 wt% was achieved maximum responsivity and quantum efficiency of R = 247.03 mA/W, QE = 95.7%, and D* = 2.84 × 1010 at 3 V. We observed that the p-Sn doped Co 3 O 4 /n-Si diodes are highly sensitive and appropriate for photo-detection applications. [ABSTRACT FROM AUTHOR]

In this work, boron doped graphene nanoparticles (NPs) were synthesized by the hydrothermal route with different boron tribromide concentrations such as 52, 104, and 156 μL. The structural, morphological and optical properties of the prepared NPs were studied using different characterization techniques such as X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), atomic force microscopy (AFM), UV–vis spectroscopy and photoluminescence spectroscopy (PL). The XRD pattern reveals the hexagonal crystal structure. The SEM image showed textured sheet-like layers which got agglomerated to form fluffy structures. The TEM images recorded single-crystalline nature and also confirms the particle size was reduced upon increasing boron tribromide solution concentration with recognizable particle shape. The topographic properties of the synthesized B-doped graphene NPs were also studied through AFM images. The UV visible absorbance characteristics peaks 243 and 372 nm were observed correspond to π – π* in C–C bands and n- π* transition. After that as grown NPs were used to fabricate diode junctions on p-Si substrates (p-Si/n-B-doped graphene). The electrical performance of each p-Si/n-B-doped graphene diodes junction was examined using I–V characteristics and electrical parameters of diode junction such as ideality factor, barrier height and reverse saturation current were found 2.9–4.3, 0.75–0.83 eV and 4.88 × 10−6-7.26 × 10−6 A. The calculated ideality factor values of the p-Si/n-B-doped graphene diodes are decreased with increase in boron tribromide solution concentration. [Display omitted] • Boron doped graphene nanoparticles were synthesized by the hydrothermal route for various concentrations of Boron tribromide. • XRD pattern exhibited a hexagonal crystal structure with sharp crystalline peak at (002) orientation. • A sheet-like surface morphology was observed through SEM image. • TEM images confirm the particle size was reduced upon increasing boron tribromide. • A minimum ideality factor of n = 2.9 was obtained for p-Si/n-B-doped Graphene diode fabricated with 156 μL. [ABSTRACT FROM AUTHOR]

Development of p-SnS:NiS (80:20)/n-Si photodiode for optoelectronic devices. [Display omitted] • Development of p-SnS:NiS and bare p-NiS/n-Si photodetectors are reported. • Phase optimization of NiS and fabrication of SnS/NiS nanocomposite. • Morphology evolution of NiS and SnS/NiS was studied on oleic acid addition. • The value of photosensitivity improved from 75.0% to 2168.1%. • The value detectivity varied from 1.45 × 109 to 5.99 × 1010 jones. Synthesis of metal chalcogenides nanostructures is of profound importance in obtaining desired properties for photo-sensing device fabrication. The present proposed work concentrates on the effect of oleic acid in the preparation of NiS and SnS/NiS composites, and their photodiode properties were examined. Synthesized NiS and SnS/NiS nanosystem characterized by XRD analysis, Raman analysis, Field Emission Scanning Electron Microscopy micrographs. Hexagonal structure of NiS and hexagonal and orthorhombic composite structures SnS/NiS composite was confirmed with XRD patterns. The single-phase SnS nanoparticle and SnS/NiS nanocomposite were confirmed with Raman analysis. The change in morphology while increasing oleic acid on the preparation of NiS and SnS/NiS as aggregated quasi sphere structures were verified with FE-SEM micrographs. SnS/NiS fabricated with different ratios, and oleic acid-assisted NiS composite particles show better photo-response, which is essential for photodiode application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Morphology tuned SnS hierarchical structures with improved photodetection are developed. • The barrier height was changed from 0.70 to 0.83 eV in dark and 0.67 to 0.77 eV under light. • The enhancement in photosensitivity from 7018.02 to 63095.6%, was noticed for p-SnS + Oleic acid (1.5 mL)/ n -Si. • An improvement in photoresponsivity (R) from 22.5 to 73.75 (mA/W) was observed for the developed SnS photodiodes. • The specific detectivity was improved from 1.01 × 1011 to 1.78 × 1011 jones for SnS photodiode. Hierarchical structure transformation and surface modification of solvothermal method synthesized SnS with oleic acid in ethylene glycol solvent were discussed in detail. The structural, optical, and morphology of as prepared SnS samples were examined by X-ray diffraction (XRD), Raman Spectroscopy, and Field Emission Scanning Electron Microscopy (FE-SEM). XRD verifies the orthorhombic crystal structure of the SnS phase for all synthesized samples. Single-phase nature of synthesized particles was confirmed with Raman characterization. Morphology evolution of SnS from regular to hierarchical structures upon adding oleic acid is performed through FE-SEM analysis. Junction diodes p-SnS/ n -Si fabricated with different oleic acid concentrations (0.5, 1.5, and 2.5 mL) synthesized SnS particles show better photo-response, which can be used in photodiode applications. [ABSTRACT FROM AUTHOR]