Electroluminescence and Photoluminescence Properties of Porous Silicon Nanostructures with Optimum Current Density of Photo-Electrochemical Anodisation

摘要

P-type silicon wafer (<100> orientation; boron doping; 0.75～10 Ω cm~(-1)) was used to prepare samples of porous silicon nanostructures (PSiNs). All samples have been prepared by using photo-electrochemical anodisation. A fixed etching time of 30 minutes and volume ratio of electrolyte, hydrofluoric acid 48% (HF48%) and absolute ethanol (C_2H_5OH), 1:1 were used for various current densities, J. There were sample A (J=10 mA/cm~2), sample B (J=20 mA/cm~2), sample C (J=30 mA/cm~2), sample D (J=40 mA/cm~2) and sample E (J=50 mA/cm~2). Photoluminescence (PL) and electroluminescence (EL) spectra were investigated. Maximum peak position of PL spectrum at about ～675 nm, while the maximum EL spectrum at about ～650 nm (which is similar to the PL spectrum).