Advanced Materials

The Origin of the Magnetism of Etched Silicon



A recent report of ferromagnetism appearing in silicon after etching in hot KOH (Kopnov et al., Adv. Mater.2007, 19, 925) is shown to be due to iron from the pyrex glassware, which precipitates on the silicon surface in the form of well-separated ferromagnetic nanoparticles. The reaction is explained in terms of the Pourbaix diagram.

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