Gallium oxide (Ga2O3) is emerging as a viable candidate for certain classes of power electronics, solar blind UV photodetectors, solar cells, and sensors with capabilities beyond existing technologies due to its large bandgap. It is usually reported that there are five different polymorphs of Ga2O3, namely, the monoclinic (β-Ga2O3), rhombohedral (α), defective spinel (γ), cubic (δ), or orthorhombic (e) structures. Of these, the β-polymorph is the stable form under normal conditions and has been the most widely studied and utilized. Since melt growth techniques can be used to grow bulk crystals of β-GaO3, the cost of producing larger area, uniform substrates is potentially lower compared to the vapor growth techniques used to manufacture bulk crystals of GaN and SiC. The performance of technologically important high voltage rectifiers and enhancement-mode Metal-Oxide Field Effect Transistors benefit from the larger critical electric field of β-Ga2O3 relative to either SiC or GaN. However, the absence of clear demonstrations of p-type doping in Ga2O3, which may be a fundamental issue resulting from the band structure, makes it very difficult to simultaneously achieve low turn-on voltages and ultra-high breakdown. The purpose of this review is to summarize recent advances in the growth, processing, and device performance of the most widely studied polymorph, β-Ga2O3. The role of defects and impurities on the transport and optical properties of bulk, epitaxial, and nanostructures material, the difficulty in p-type doping, and the development of processing techniques like etching, contact formation, dielectrics for gate formation, and passivation are discussed. Areas where continued development is needed to fully exploit the properties of Ga2O3 are identified.

A review of Ga2O3 materials, processing, and devices

Ongoing advances in nanotechnology research have established a variety of methods to synthesize nanoparticles (NPs) from a diverse range of materials, including metals, semiconductors, ceramics, metal oxides, polymers, etc. Depending upon their origin and synthesis methods, NPs possess unique physicochemical, structural and morphological characteristics, which are important in a wide variety of applications concomitant to electronic, optoelectronic, optical, electrochemical, environment and biomedical fields. This review provides a comprehensive overview on various physical, chemical and bio-assisted methods largely employed to synthesize and fabricate NPs of varying size, surface characteristics, functionalities and physicochemical behavior. The key applications of nanoparticles have also been discussed.

Methods and strategies for the synthesis of diverse nanoparticles and their applications: a comprehensive overview

Therapeutic effects of herbal extracts and constituents in animal models of psychiatric disorders.

Triticum aestivum L.

Due to its significant applications in many relevant fields, light detection in the solar-blind deep-ultraviolet (DUV) wavelength region is a subject of great interest for both scientific and industrial communities. The rapid advances in preparing high-quality ultrawide-bandgap (UWBG) semiconductors have enabled the realization of various high-performance DUV photodetectors (DUVPDs) with different geometries, which provide an avenue for circumventing numerous disadvantages in traditional DUV detectors. This article presents a comprehensive review of the applications of inorganic UWBG semiconductors for solar-blind DUV light detection in the past several decades. Different kinds of DUVPDs, which are based on varied UWBG semiconductors including Ga2O3, MgxZn1−xO, III-nitride compounds (AlxGa1−xN/AlN and BN), diamond, etc., and operate on different working principles, are introduced and discussed systematically. Some emerging techniques to optimize device performance are addressed as well. Finally, the existing techniques are summarized and future challenges are proposed in order to shed light on development in this critical research field.

Recent Progress in Solar-Blind Deep-Ultraviolet Photodetectors Based on Inorganic Ultrawide Bandgap Semiconductors

In the present work, we have investigated the effect of deposition time on the morphological, structural, and photoluminescence (PL) properties of β-Ga2O3 NWs grown by CVD technique. The diameter and length of the as-grown NWs varied for the deposition time of 1–4 h, from 50 to 100 nm and 5–15 μm, respectively. The crystalline quality of the NWs improved with increasing the deposition time. The detailed transmission electron microscopy (TEM) and fast Fourier Transformation (FFT) measurements revealed that the as-grown β-Ga2O3 NWs were single crystalline. Furthermore, we have studied the variation of PL spectra of the NWs with deposition time and provided an energy band diagram to give a plausible explanation of the origin of different emissions in the PL spectra. The PL spectra showed a broad strong UV-blue emission band and a weak red emission for 1 h deposited sample. We suggested that the UV and red emission from β-Ga2O3 NWs are related to oxygen vacancies and impurities such as nitrogen, respectively. It was observed that the intensity of UV emission decreased with deposition time and this reduction was attributed primarily to the reduction of oxygen vacancies in the NWs.

The effect of deposition time on the structural and optical properties of β-Ga 2 O 3 nanowires grown using CVD technique

Point defects induced work function modulation of β-Ga2O3

In this paper, we demonstrate a new catalyst (Fe) to grow single crystalline beta-gallium oxide (?-Ga2O3) nanowires (NWs) via the vapour?liquid?solid mechanism using the chemical vapour deposition technique. The structural studies of these NWs showed the highly crystalline monoclinic phase of Ga2O3. This was confirmed by detailed scanning transmission electron microscope investigations demonstrating the NW to be single crystalline ?-Ga2O3, growing along the normal of the plane. We also compared Raman and cathodoluminescence (CL) properties of the as-grown ?-Ga2O3 NWs with a bulk Ga2O3 single crystal grown by the Czochralski method. It was observed that Raman peak positions of a single ?-Ga2O3 NW had a red frequency shift of about 0.3?1.4?cm?1 as compared to a bulk Ga2O3 single crystal, which was in fact quite small. In addition, the CL measurements of ?-Ga2O3 NWs and the bulk Ga2O3 single crystal exhibited similar spectra, having a strong broad UV?blue emission band and a weak red emission band. Moreover, the structural, morphological and optical properties of Fe-catalysed ?-Ga2O3 NWs were comparable to those of Au-catalysed ?-Ga2O3 NWs.

https://iopscience.iop.org/article/10.1088/0022-3727/47/43/435101/pdf

Study of iron-catalysed growth of beta-Ga2O3 nanowires and their detailed characterization using TEM, Raman and cathodoluminescence techniques

The antibacterial resistant pattern of aerobic bacteria, isolate from burn patients admitted in plastic surgery & general surgery wards of Chhatrapati Shahuji Maharaj Medical Uni-versity, Lucknow (a tertiary care hospital) were studied. 100 patients were enrolled from plastic surgery & general surgery wards and 200 samples were collected which comprised of 100 burn wound swabs & 100 biopsies of same patients. All samples were cultured on Nutrient agar, Mac conkey agar and Blood agar at 37oc for 24 hrs. The isolates were identified by culture, staining and biochemical tests including oxidase, lactose and maltose fermentation, catalase and their antibiotic sensitivity determined using Kirby Bauer disc diffusion technique. The most common isolate was Pseudomonas aeruginosa-55.0%, followed by Staphylococcus aureus-19.29%, Klebsiella spp.-11.43%, Acinetobacter spps-7.14%. Proteus spp 4.29%, Es-cherichia coli-2.85%. Resistance of S.aureus was 40% observed with Oxacillin & 84% to Erythromycin whereas all strains were susceptible to Vancomycin. We analyzed that pesu-domonas which was the commonest isolate was most resistant to Ceftazidime (70%) followed by Cefotaxime. Ciprofloxacin (55.5%) & Amikacin (54.0%) were found to be most effective antimicrobial agent (7, 11). Other Gram-negative organisms were highly resistant to Cefo-taxime (66.0%) followed by Gentamycin (60.0%).). Imipenem was found to be less resistant (26%) against Pseudomonas.

/pdf/antibacterial-resistance-pattern-of-aerobic-bacteria-44vrhiyhkz.pdf

Antibacterial resistance pattern of aerobic bacteria isolates from burn patients in tertiary care hospital

https://iopscience.iop.org/article/10.1149/2.0291907jss/pdf

R.K. Singh

Papers

The effect of deposition time on the structural and optical properties of β-Ga 2 O 3 nanowires grown using CVD technique

Point defects induced work function modulation of β-Ga2O3

Study of iron-catalysed growth of beta-Ga2O3 nanowires and their detailed characterization using TEM, Raman and cathodoluminescence techniques

Antibacterial resistance pattern of aerobic bacteria isolates from burn patients in tertiary care hospital

Gamma Irradiation Effect on Performance of β-Ga2O3 Metal-Semiconductor-Metal Solar-Blind Photodetectors for Space Applications