The photoluminescence (PL) properties of porous silicon (PS) have been studied based on n-type single- crystal (111) silicon wafers (80-90Ω .cm in the resistivity). The porous silicon layers (PSL) were created by anodizing the wafers with a denuded zone of 20-40 μm formed by neutron transmutation doping (NTD) and thermal treatment at 940℃ for 4 h and then 700℃ for 2 h, two-step heating of the floating-zone silicon (FZ Si) grown in a hydrogen (H2) ambience. By surface modification with stannic chloride or amine immersion and rapid thermal oxidation (RTO), the PL peak position from the PS can be qualitatively controlled factitiously. The as-prepared PS shows an orange-yellow luminescence, while the modified samples emit red, green and blue luminescence. Mechanisms for the different colors of the PL are discussed. Fourier transform infrared (FTIR) is carried out to analyze the differences in the structural configuration of the PS samples.
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