Figure 2.

GaAs nanowires catalyzed by Au thin film of different thicknesses. The substrates are tilted 30° to give better views of the nanowires. (a to e) GaAs nanowire grown with 0.5-, 1-, 2-, 3-, and 5-nm Au thin films, respectively. (f to h) Individual views of GaAs nanowire catalyzed by 2-, 3-, and 5-nm Au thin films, respectively.