Continuous and uniform graphene films were directly grown on SiO 2 substrates using a chemical vapor deposition system with two-temperature zones assembled. The carbon species from the high temperature zone nucleate in the low temperature zone, initiating the growing process of graphene. The films are

Direct deposition of a uniform and high-quality Bi2Se3 thin film on a graphene film (layer controlled) is performed using a catalyst-free vapor deposition system in a Se-rich environment.

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Amorphous gallium nitride doped with Mn thin films was deposited on sapphire (0001) substrates by laser molecular beam epitaxy. After simple processing of annealing at different temperatures for 30 min in ammonia atmosphere, good quality Ga 12x Mn x N films were obtained. In order to investigate the influence of annealing temperature on the crystalline quality and structural and magnetic properties, the films are analysed by X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy and alternating gradient magnetic field meter. The results show that the annealing can improve the quality of Ga 12x Mn x N films, and the optimum annealing temperature is 1050uC; moreover, there is no second phase forming. Through magnetic analysis, we obtained the annealed samples of room temperature ferromagnetic property and paramagnetism of the as grown film and obtained the way of changing the paramagnetism into ferromagnetism using the simple method.

The amorphous gallium nitride thin films doped with Mn were deposited by Laser assisted Molecular Beam Epitaxy (LMBE). After annealing at different NH 3 flow rates, the high-quality GaMnN crystalline films with different concentration of nitrogen vacancies (V N ) were obtained, which were confirmed by the X-ray diffraction spectroscopy and Raman measurements. The magnetic behaviors of these films were also obtained to investigate the effects of nitrogen vacancies. It indicates that V N play a significant role in the origin of ferromagnetism. The stronger room-temperature ferromagnetism is given with the higher V N concentration when it is not beyond a critical concentration. Moreover, from our M(T ) curves and Raman analysis, the films present high resistivity. The magnetism of films with high resistivity varies with concentration of nitrogen vacancies, which can be explained by the bound magnetic polarons (BMP) theory.