Figure 7
Nanostructures on micro pits obtained using the dry etching method: (a) top view of a low-magnification micrograph, (b) nanostructures on the profile of the pits, and (c) high-magnification SEM image of nanostructures on the profile. (a) Shows an image of the nanostructures grown on micro pits using the dry etching method, with a magnified view in (b). (b) Indicates that nanostructures are growing well on the bottom of the pits, with a height of approximately 1 μm, but no growth occurs on the profile close to the top surface. (c) Shows a relatively dense grass that is denser than that obtained for the flat growth conditions using the wet etching method (Fig. 5(c)) but less dense than that obtained for the tip growth condition with the gas method (Fig. 6(c)).
