Enhancement in the Photoluminescence of Porous Silicon by Sputter Deposition of Semitransparent Metal Films

초록

Optoelctronic devices based on porous silicon(PS) undergo substantial degradation in luminescence with aging due to atmospheric oxidation. It has been reported that passivation of PS with a transparent conducting material or a semi-transparent metal. In this paper we report enhancement in the photoluminescence(PL) of PS by passivation of PS with ultrathin metal films such as silver(Ag), aluminum(Al), and gold(Au). It has been found that Ag and Al are the most and the least effective in enhancing the PL of PS among those three different metals, respectively. The highest PL enhancing effect of Ag is mostly attributed to the lowest optical transmittance and the highest oxidation resistance of Au. The details of PL enhancing effect of metal passivation are discussed by employing FTIR analysis.