| In this paper, crystalline boron films and amorphous boron films were grown by magnetron sputtering. Scanning electron microscopy (SEM) equipped with energy diffraction spectrum (EDS) is used to study the microstructure and chemical compositions of these films. Transmission electron microscopy (TEM) is employed for the selected area electron diffraction (SAED). And nanoindentor is used to mensurate the elasticity-modulus and nano-hardness. Boron nanowires were also fabricated by magnetron sputtering with gold catalyst. SEM is employed to study the microstructure, EDS/TEM/electron energy loss spectrum (EELS) are used to detect the chemical compositions. The effect of sputtering parameters on the growth of nanowires is studied systemically and the growth mechanism is also discussed. The results suggest that with increasing of sputtering pressure, both the density and nano-hardness of the films are improved, but pressure has little influence on the elasticity-modulus. The amorphous boron films deposited at different substrate temperatures show that with the temperature decreasing, the elasticity-modulus and nano-hardness decrease because of the porosity in the boron films. Boron nanowires on the films are investigated in detail. It can be concluded that the critical temperature for the growth of nanowires is 600 ℃. A longer sputtering time, a higher substrate temperature and a higher sputtering pressure are favorable to obtain the crystalline boron nanowires. The growth of boron nanowires is probably controlled by combination of vapor-liquid-solid (VLS) and vapor-cluster-solid (VCS) mechanisms.
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