Synthesis and Characterization of Bifacial Porous Silicon Modified with Tri-Metal Nanocomposites

Abstract

This research presents a novel approach to effectively modify the characteristics of bifacial porous silicon (B-PSi) layers using tri-metallic nanoparticles. The B-PSi was synthesized by double beam laser-induced etching (D-LIE) of an n-type silicon substrate using 533-nm wavelength lasers at 80-mW power. Tri-metallic nanoparticles with a core/shell configuration, composed of Au, Ag, and Pd, were then incorporated onto the B-PSi surface through a dipping process in a solution with a 1:1:1 volumetric ratio of HAuCl4, AgNO3, and PdCl2 at 2-mM concentration for 4 min. The structural, spectroscopic, and morphological properties of the bare B-PSi were significantly modified by the deposition of the tri-metallic nanoparticles. Notably, the bifacial faces of the porous silicon layer exhibited a high degree of symmetry in terms of grain sizes of the tri-metallic nanoparticles, surface morphology, photoluminescence emission, and chemical bonding, both before and after nanoparticle deposition. This simple yet novel approach demonstrates an effective method for tailoring the characteristics of bifacial porous silicon layers through the integration of tri-metallic nanostructures.