Photoluminescence Properties of LaF₃-Coated Porous Silicon

Sinthia Shabnam Mou, Md. Johurul Islam, Abu Bakar Md Ismail

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DOI: 10.4236/msa.2011.26089                

Abstract

This work reports the coating of porous silicon (PS) with LaF3 and its influence on the photoluminescence (PL) property of PS. PS samples, prepared by electrochemical etching in a solution of HF and ethanol, were coated with e-beam evaporated-LaF₃ of different thicknesses. It was observed that the thin LaF₃ layer on PS led to a good enhancement of PL yield of PS. But with the increasing thickness of LaF₃ layer PL intensity of PS was decreasing along with a small blue-shift. It was also observed that all the coated samples showed degradation in PL intensity with time, but annealing could recover and stabilize the degraded PL.

Keywords

Porous Silicon, Anodic Etching, Photoluminescence, Surface Coating, Photonics

Conflicts of Interest

The authors declare no conflicts of interest.

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