Photoirradiation Caused Controllable Wettability Switching of Sputtered Highly Aligned c-Axis-Oriented Zinc Oxide Columnar Films

Figure 4

Atomic force microscope (AFM) 3D images for the ZnO thin films with different RF powers of (a) 50, (c) 75, (e) 100, and (g) 150 W; (b), (d), (f), and (h) are the corresponding 2D surface images for (a), (c), (e), and (g) forms, respectively. The scanning size of all domain images was fixed at 1 × 1 𝜇m². (i) The surface roughness values as a function of the ZnO thin films with different deposition powers ranged from 50 to 150 W.

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