Nanowires bismuth nanowire arrays

Fig. 6. (a) SEM image of the bottom surface of an anodic alumina template filled with bismuth. The pore diameter is 42 nm. (b) TEM micrograph of the cross section of a 65-nm bismuth nanowire array (Zhang et al., 1999). 

Figure 8 shows X-ray diffraction (XRD) patterns of bismuth nanowire arrays (Lin et al., 2000b). It illustrates that the crystal structure of bismuth nanowires is the same as that of bulk bismuth and that no copper phases were present. The nanowires have a preferred wire orientation dependent on their diameters. The major orientations of the 95-nm and 40-nm bismuth nanowire arrays were normal to the (202) and (012) lattice planes, respectively, indicating that most (> 80%) of the nanowires were oriented along the [1011] and [0112] directions for <7W > 60 nm and <7W < 50 nm, respectively (Zhang et al., 1999 Lin et al., 2000b). The existence of more than one dominant orientation in the 52-nm Bi nanowires (Fig. 8(b)) was... 

Figure 19(a) shows the temperature dependence of resistance R(T) for bismuth nanowire arrays (dw = 7 - 200 nm) synthesized by vapor deposition and measured by Heremans et al. (2000). Hong et al. (1999) reported similar resistance measurements on bismuth wires of larger diameters (200 nm to 2, uni) prepared by electrochemical deposition (Fig. 19(b)). These two studies... 

Fig. 19. (a) Measured temperature dependence of resistance for bismuth nanowire arrays of various wire diameters dw (Heremans et al, 2000). (b) R(T)/R(290 K) for bismuth wires of larger dw measured by Hong et al. (1999). (c) Calculated R(T)/R(300 K) of 36-nm and 70-nm bismuth nanowires (Lin et al, 2000b). The dashed curve refers to a 70-nm poly crystalline wire with increased boundary scattering. 

Zhang, Z., Sun, X., Dresselhaus, M. S., Ying, J. Y., and Heremans, J., Magnetotransport investigation of ultrafine single-crystalline bismuth nanowire arrays. Appl. Phys. Lett. 73,1589 (1998c). 

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