Competitive growth of branched channels inside AAO membranes

A competitive model accounting for the growth of branched channels inside AAO membranes is proposed in this paper. According to this model, two types of competition which originate from the non-uniform thinning of stem channel barrier layers result in the tree-like morphology of branched channels. Furthermore, competitive growth can be suppressed or eliminated by thinning the barrier layers of stem channels before the second step anodization. Experimental results have confirmed this growth model and indicate that controllable uniform branched channels on a large scale can be obtained by the assistant of moderate chemical etching to adjust the starting thickness of the barrier layers.