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The Be films were prepared on the water-cooled substrates and heated substrates by thermal evaporation, respectively. The experiment of water-cooled substrate showed the grains in Be films grown on Si substrates were refined than those grown on glass substrates and the surface roughness of Be films grown on Si substrates was also improved. The electrical performance test suggested that the electrical resistivity of Be films grown on water-cooled substrates decreased with increasing the heating temperature and was bigger than that grown on non-water-cooled substrates. For the experiment of heated substrate, the Be films appeared the loose flocculent structure, and the surface roughness firstly increased from 8 nm to 45–65 nm in the range of 150–300 °C and then decreased to 10 nm at 400 °C. Meanwhile, its electrical resistivity sharply increased from 0.6 Ω/□ to 206.6 Ω/□ due to the gradual oxidization at high temperature, especially 400 °C. [ABSTRACT FROM AUTHOR]

Beryllium carbide films without columnar-crystal microstructures were prepared on the Si (1 0 0) substrate by thermal metal organic chemical vapor deposition using diethylberyllium as precursor. The influence of the substrate temperature on composition and microstructure of beryllium carbide films was systematically studied. Crystalline beryllium carbide is always the dominant phase according to XRD analysis. Meanwhile, a small amount of α-Be phase exists in films when the substrate temperature is below 400 °C, and hydrocarbon or amorphous carbon exists when the temperature is beyond 400 °C. Surfaces morphology shows transition from domes to cylinders, to humps, and to tetraquetrous crystalline needles with the increase of substrate temperature. No columnar grains are characterized throughout the thickness as revealed from the cross-section views. The average densities of these films are determined to be 2.04–2.17 g/cm 3 . The findings indicate the substrate temperature has great influences on the composition and microstructure of the Be 2 C films grown by thermal MOCVD. [ABSTRACT FROM AUTHOR]

Grain refinement of beryllium deposits is studied as a significant subject for beryllium capsule in the Inertial Confinement Fusion project. The Be films were prepared on the Si (1 0 0) substrates by thermal evaporation with and without a magnetic field, respectively. The two separate groups of prepared Be films were characterized. The results showed the grain diameter in the Be film transited from 300 nm to 18 nm and the surface roughness of the Be film decreased from 61 nm to 3 nm by application of the magnetic field during the deposition process of Be coating. However, the Be film grown with the magnetic field was easily oxidized in comparison with that grown without magnetic field due to the refined grains, and the oxidation was gradually decreased with the increase of etching depth in the Be film. The reason for grain refinement of Be film was also qualitatively described. [ABSTRACT FROM AUTHOR]