Electrochemically oxidised porous silicon microcavities

Ageing effects in porous silicon microcavities result in emission enhancement and resonance peak blueshift. In this paper we propose electrochemical oxidation as a method to control these effects. Properties of porous silicon microcavities obtained after anodic oxidation are compared to those of microcavities aged in air for several months. This evidences that emission enhancement and resonance peak shift are two different phenomena and the effects of anodic and naturally oxidation are not the same. A significant suppression of peak shift due to ageing is achieved, and the extent of this stabilisation increases with the oxidation time, but for long oxidation times the microcavity properties are degraded.