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A group of porous silicon (PSi) samples with different surface morphologies prepared at different etching
current densities were investigated as a substrate for formation of silver nanoparticles (AgNPs). Simple
dipping process of PSi in silver nitrite (AgNO3) with concentrations of 103, 102, and 5 102 M was
employed to synthesize AgNPs.
The p-type PSi was prepared by electrochemical etching process at different values of current densities. Three different forms of PSi morphology; meso, macro, and pillar with different roughness values
1.21, 177, 89.5, and 38.7 nm were prepared with varying the current densities 30, 60, 90, and 120 mA/cm2
respectively. The structural and surface morphology properties of samples before and after dipping in
AgNO3 were studied through analyzing of scanning electron microscopy (SEM), atomic force microscopy
(AFM), and X-ray diffraction (XRD). The results show that the AgNPs sizes depend on the surface
morphology and roughness of PSi. The AgNPs prepared by dipping process does not depend on the
porosity of the porous layer. For meso pore-like structures the sizes of AgNPs were in the range from 0.52
to 4.09 mm for a low surface roughness, and from 0.52 to 6.83 nm for high surface roughness. For the case
of macro pore-like structure which possesses the highest pore sizes and surface roughness, the AgNPs
sizes vary from 0.61 to 3.42 mm. The minimum AgNPs size of about 190 nm was obtained from porous
surface of pillar form.
Keywords
Porous silicon; Surface morphology; Silver nanoparticles; Immersion plating
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