Spontaneous formation of microgroove arrays on the surface of p-type porous silicon induced by a turing instability in electrochemical dissolution

Abstract Self-organization plays an imperative role in recent materials science. Highly tunable, periodic structures based on dynamic self-organization at micrometer scales have proven difficult to design, but are desired for the further development of micropatterning. In the present study, we report a microgroove array that spontaneously forms on a p-type silicon surface during its electrodissolution. Our detailed experimental results suggest that the instability can be classified as Turing instability. The characteristic scale of the Turing-type pattern is small compared to self-organized patterns caused by the Turing instabilities reported so far. The mechanism for the miniaturization of self-organized patterns is strongly related to the semiconducting property of silicon electrodes as well as the dynamics of their surface chemistry. Spontaneously getting a groove on: The spontaneous formation of a microscopic Turing-type pattern on a semiconductor electrode is reported. It is shown that the microscopic scale of the pattern is not determined by the ratio of activator and inhibitor, but by the reaction dynamics.