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The floating zone (FZ) is one of the important methods for pulling silicon single crystals, but there are still problems of an unstable thermal field and crystallization difficulties. They will directly affect the growth of single crystals, resulting in defects and even fractures, seriously reducing production efficiency. Based on this, the effect of the modified inductor structure on the FZ thermal field is investigated in this paper. Using COMSOL 6.0 simulation software, 2D and 3D FZ models are established. The inductor steps under the 2D model and the inductor slits under the 3D model are compared to analyze the effects of steps and slits on the 8-inch FZ thermal field and melt flow. The distributions of temperature fields and melt flow in the melting zone under the action of the axial magnetic field are calculated by finite element analysis. The results show that the melt under the introduction of steps in the 2D model and the cross-slit structure in the 3D model is the most stable and favorable for crystal growth, which matches the actual production. [ABSTRACT FROM AUTHOR]

Silicon-on-insulator (SOI) devices have many advantages, such as high speed, low energy consumption, radiation-hard, and high integration. In this paper, the separation by implanted oxygen process under low-dose implantation conditions is studied by the two-step implantation method combined with the internal thermal oxidation process. The effects of different types of silicon wafers and different implantation doses on SOI surface defects, top Si thickness, buried oxide (BOX) layer thickness, BOX layer breakdown voltage, and top Si defect density were investigated. Ultra-thin SOI wafers are prepared by epitaxial silicon wafers and control the first implantation dose. The number of surface defects of SOI materials is less than 100 counts, the breakdown voltage of the BOX layer is about 7.8 MV/cm, and the top Si dislocation density is about 8 × 103 cm−2. [ABSTRACT FROM AUTHOR]

In this paper, AlN thin films are fabricated by green and efficient metal nitride vapor phase epitaxy (MNVPE). First, AlN films are grown on c‐plane sapphire substrates at different molar flow ratios (V/III ratios) of the source material, and the effects of V/III on the crystal quality and surface morphology of the films are investigated. The growth conditions are kept constant (growth temperature of 1550 °C, growth pressure of 10 kPa, V/III ratio of 4420), and the AlN thin films are prepared by heterogeneous epitaxial growth on c‐plane sapphire, silicon (111), and GaN substrates. The crystal quality, residual stress, and luminescence properties of epitaxial AlN thin films on the three substrates are investigated using X‐ray diffraction, scanning electron microscopy, Raman spectroscopy, photoluminescence, and UV spectrophotometer. Among them, the FWHM value of the sample AlN/GaN (002) plane can reach 338 arcsec. The residual stress in samples AlN/Sapphire, AlN/GaN and AlN/Si are 1027, −81, and −541 MPa, respectively, and the sample AlN/GaN has fewer point defects. At the same time, a 50‐nanometer‐thick void layer appears in the AlN thin film samples prepared on GaN substrates, which provides a new technical idea for realizing large‐scale and high‐quality self‐supporting AlN thin films. [ABSTRACT FROM AUTHOR]

CO2 reduction with water and light illumination is realized using a nitride (InxGa1-xN) photoelectrode that separates pairs of electrons and holes, thereby driving oxidation and reduction reactions. InxGa1-xN is a promising material for photocatalysis due to its tuneable band gap and excellent optical properties. However, little research has been done on the effect of In contents on CO2 reduction in InxGa1-xN. In this work, the photocatalytic performance of different In contents of InxGa1-xN photoanodes and the electrode's corrosivity in the process of artificial photosynthesis were studied. We found that the photoanode containing 0.9% In enhanced the conversion to CO, CH4, C2H4, and C2H6. Our photoluminescence spectroscopy, scanning electron microscopy, and X-ray diffraction results suggested that photo-corrosion occurs on the photoanode's surface at the end of the reaction. [ABSTRACT FROM AUTHOR]

Successful growth of c-axis oriented aluminum nitride (AlN) films with uniform columnar structure on (0006) sapphire substrates by Radio Frequency (RF) reactive magnetron sputtering. In this paper, the crystal structure and morphological characteristics of AlN films were changed by varying the nitrogen (N2) flow ratio in the mixture of N2 and argon (Ar) gas, i.e., N2/(Ar + N2). Transmission electron microscopy and X-ray diffractometer analysis confirmed that the AlN films first formed a buffer layer at the interface and subsequently exhibited a high degree of c-axis orientation. Combined atomic force microscopy and scanning electron microscope tests show that the surface undulations of the AlN films were very small reaching a root mean square (RMS) surface roughness of 0.2750 nm. The X-ray photoelectron spectroscopy spectra confirmed the formation of AlN. Finally, the optical band gap and defect types of the films were determined by ultraviolet and visible spectrophotometry and photoluminescence spectrum. [ABSTRACT FROM AUTHOR]

In Fig. 5(b), The In0.009GaN0.0991/GaN should be changed to In0.071 GaN0.0929/GaN. The author apologizes for this error. [ABSTRACT FROM AUTHOR]