Φ80 mm‐diameter, highly <110>‐oriented β‐SiC wafers were ultra‐fast fabricated via halide chemical vapor deposition (CVD) using tetrachlorosilane (SiCl4) and methane (CH4) as precursors. The effects of deposition temperature (Tdep) and total pressure (Ptot) on the orientations, microstructures, and deposition rate (Rdep) were investigated. Rdep dramatically increased with increasing Tdep where maximum Rdep was 930 μm/h at Tdep = 1823 K and Ptot = 4 kPa, leading to a maximum of 1.9 mm in thickness in 2 h deposition. The <110>‐oriented β‐SiC was obtained at Tdep > 1773 K and Ptot = 1–4 kPa. Growth mechanism of <110>‐oriented β‐SiC has also been discussed under consideration of crystallographic planes, surface energy, and surface morphology.

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Highly-oriented polycrystal 3C-SiC bulks were ultra-fast fabricated via halide chemical vapor deposition (CVD) using tetrachlorosilane (SiCl4) and methane (CH4) as precursors. The effects of deposition temperature (Tdep) and total pressure (Ptot) on the orientation and surficial morphology were investigated. The results showed that the growth orientation of 3C-SiC columnar grains was strongly influenced by Tdep. With increasing Tdep, the columnar grains transformed from <111>- to <110>-oriented. The arrangement of <111>-oriented columnar grains was controlled by Ptot. Lotus-, turtle-, thorn-, and strawberry-like surface morphologies were naturally contributed by different arrangements of <111>-oriented grains, and the deposition mechanism was discussed. The wetting behaviors of CVD-SiC samples by molten aluminum were also examined at 1173 K in a high vacuum atmosphere.

Layer-structured InSe is one of the intensively studied two-dimensional monochalcogenide semiconductors for optical and electrical devices. Significant features of the InSe device are the thickness dependent bandgap modification resulting in a peak shift of photoluminescence and a drastic variation of electron mobility. In this study, by applying the pulsed-laser deposition technique, we investigated the optical and electrical properties of c-axis oriented InSe films with the thickness varying from a few to hundred nanometers. The energy at the absorption edge systematically shifts from about 3.3 to 1.4 eV with the increasing thickness. The InSe films on Al2O3(0001) are highly resistive, while those on InP(111) are conductive, which probably originates from the valence mismatch effect at the interface. The electron mobility of the conducting charge carrier at the interface of InSe/InP is enhanced in thicker samples than the critical thickness of about 10 nm, corresponding to the bandgap modification characterized by the optical measurement. Therefore, the substrate and the film thickness are critically important factors for the materialization of InSe optical and electrical device applications.