Wet-Chemical Surface Texturing of Sputter-Deposited ZnO:Al Films as Front Electrode for Thin-Film Silicon Solar Cells

Figure 7

((a) and (c)) Power spectral density (PSD) function and ((b) and (d)) corresponding autocorrelation length and RMS roughness derived from AFM measurements for two-step textured AZO films using (left) 1% HF etching for 20 s and then 0.5% HCl etching from 0 to 40 s, (right) 0.5% HCl etching for 20 s, and then 1% HF etching from 0 to 40 s.