Comparative study of initial stages of copper immersion deposition on bulk and porous silicon

Abstract

Initial stages of Cu immersion deposition in the presence of hydrofluoric acid on bulk and porous silicon were studied. Cu was found to deposit both on bulk and porous silicon as a layer of nanoparticles which grew according to the Volmer-Weber mechanism. It was revealed that at the initial stages of immersion deposition, Cu nanoparticles consisted of crystals with a maximum size of 10 nm and inherited the orientation of the original silicon substrate. Deposited Cu nanoparticles were found to be partially oxidized to Cu2O while CuO was not detected for all samples. In contrast to porous silicon, the crystal orientation of the original silicon substrate significantly affected the sizes, density, and oxidation level of Cu nanoparticles deposited on bulk silicon.

Near UV‐Irradiation of CuOx‐Impregnated TiO2 Providing Active Species for H2 Production Through Methanol Photoreforming

“…Actually, island‐like morphology of copper species on TiO 2 surface suggests deposition‐reduction process occurred according to the Volmer‐Weber mechanism . Notably, the lattice parameters of the substrate, significantly affect the sizes and oxidation level of Copper deposits.…”

Impact of Surface Chemistry on Copper Deposition in Mesoporous Silicon

“…Spontaneous Cu deposition has been reported upon immersion of PSi in aqueous solutions containing cupric ions as a result of the reductive character of this material. − , Cu deposition has also been reported from a solution in methanol . Here, the metallization of the PSi samples was carried out by impregnation with a solution of CuMes in [C 1 C 4 Im]­[NTf 2 ].…”

“…containing cupric ions as a result of the reductive character of this material. [8][9][10][11]17 Cu deposition has also been reported from a solution in methanol. 16 Here, the metallization of the PSi samples was carried out by impregnation with a solution of CuMes in…”

“…By contrast, fluid carriers capable of wetting the pores allow for a deeper penetration of metal atoms into the porous layer and more uniform metallization . In general, impregnation by aqueous solutions is efficient only at metallizing the surface but not the internal structure of this hydrophobic material. − However, aqueous solutions with suitable wetting agents have been successfully used to thoroughly metallize mesoporous Si layers either by electrolytic or chemical deposition. − In some instances, this reaction needs to be assisted by sonication …”

Characterization of Copper Nanostructures Grown on Porous Silicon by Displacement Deposition

“…The pore channel diameter limits the size of the grains, while on the outer PS surface crystals of copper can be in tens times higher, exceeding in some cases, the nanometer range. EBSD analysis of the outer PS surface (the analyzed thickness has been about 100 nm) after the copper deposition has shown that during the nucleation of grain and its initial growth to 2 nm metal inherits the crystallographic orientation of the initial silicon wafer (13). Further copper crystals growth leads to the coalescence of NPs into large aggregates or quasi continuous film.…”