Figure 2From: Controlling interferometric properties of nanoporous anodic aluminium oxideTypical SEM images of nanoporous AAO prepared by Al anodization in 0.3 M oxalic acid. (a) Top surface (50 V); (b) cross-sectional structure (50 V for 40 min); (c) graph showing the dependence of dp and anodization voltage (30 to 70 V); and (d) graph showing the dependence of lp and anodization time (from 10 to 60 min) under a constant anodization voltage (50 V).Back to article page