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Ultraviolet photodetectors have been widely utilized in several applications, such as advanced communication, ozone sensing, air purification, flame detection, etc. Gallium nitride and its compound semiconductors have been promising candidates in photodetection applications. Unlike polar gallium nitride-based optoelectronics, non-polar gallium nitride-based optoelectronics have gained huge attention due to the piezoelectric and spontaneous polarization effect–induced quantum confined-stark effect being eliminated. In turn, non-polar gallium nitride-based photodetectors portray higher efficiency and faster response compared to the polar growth direction. To date, however, a systematic literature review of non-polar gallium nitride-based photodetectors has yet to be demonstrated. Hence, the objective of this systematic literature review is to critically analyze the data related to non-polar gallium nitride-based photodetectors. Based on the pool of literature, three categories are introduced, namely, growth and fabrication, electrical properties, and structural, morphological, and optical properties. In addition, bibliometric analysis, a precise open-source tool, was used to conduct a comprehensive science mapping analysis of non-polar gallium nitride-based photodetectors. Finally, challenges, motivations, and future opportunities of non-polar gallium nitride-based photodetectors are presented. The future opportunities of non-polar GaN-based photodetectors in terms of growth conditions, fabrication, and characterization are also presented. This systematic literature review can provide initial reading material for researchers and industries working on non-polar gallium nitride-based photodetectors.

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The investigation was concentrated on preparation of bioactive pure cordierite ceramic and evaluate the phase transformation which excepted to form during sintering process. Cordierite prepare by chemical co precipitation, integrated Cordierite gel with water-based sol–gel which begin essentially from Alumina Al2O3, magnesium oxide MgO and silicon oxide SiO2. Different specimens were fabricated with various weight percentage of Al2O3, Mgo and SiO2 powders. All specimens were prepared in cylindrical shape by using hydraulic press at pressure of 4 bar with holding time at this pressure for 30 minutes. Firing presses achieve at 10000C and 12500C with 2 hour holding time. The characterization of microstructure has been done by using Field Emission Scanning Electron Microscope (FESEM), which revealed homogenous distribution of the compounds with few porosities. The x-ray diffraction for phase transformation which occur during sintering process. The structure analysis of specimens shows at 1250°C cordierite phase form, also the results are shown formation of cristobalite, spinel, protoestatite and corundum with cordierite phase.

This paper presents a slotted planar microstrip patch antenna for the 5th generation communication. The planar microstrip patch antenna is designed with a square patch and two longitude slots at 3.5 GHz, using FR4 substrate and feds by a coplanar waveguide structure (CPW). The proposed antenna was simulated, analysed, and optimized using computer simulation technology (CST) software. Simulation results show a good return loss of greater than10 dB and impedance bandwidth of about 650MHz, which meet the requirements of future 5G applications. In this work, the geometry of the presented antenna and its related parameters are presented and discussed