Figure 7
SEM images of PdSi-catalyzed NW. (a-c) are grown at P tot = 15 Torr, and a ratio PHCl/PSiH4 = 3.3 (200 mTorr/60 mTorr) for 10 min at different temperatures: (a) T = 600°C, (b) T = 700°C, (c) T = 800°C. NW shown on (d) are grown at P tot = 3 Torr, and at a ratio P HCl/P SiH4 = 4 for 15 min at 800°C. In this condition, there is no tapering of the NW. The inset in Figure 4d shows a SEM image of the catalyst after growth. The cylindrical-faceted shape is typical of VSS growth.