Luminescence of porous silicon after electrochemical oxidation

* Final gross prices may vary according to local VAT.

Get Access

Abstract

One of the most commonly used hypothesis to explain the light emission in the visible range from porous silicon is the confinement of charge carriers in the quantum sized crystallites which are formed in the material [1] [2] [3]. The rather good emission efficiency which is obtained also supposes an efficient passivation of the large specific surface of the material. Such passivation is readily obtained just after formation of the porous layer, and it is provided by the Si-H surface coverage which results from the anodic attack of the crystalline silicon in hydrofluoric acid (HF) solutions [4]. However, this passivation is not permanent, and the result is that photoluminescence degradation is often observed, for example upon annealing [5] or under illumination.