Synthesis of Large-Area Silicon Nanowire Arrays via Self-Assembling Nanoelectrochemistry

Single Crystalline Mesoporous Silicon Nanowires

“…The synthetic method described in this study, on the other hand, relies on an electroless metal deposition process to provide the current flux necessary for porous silicon formation. Electroless metal deposition and subsequent sacrificial etching of the surrounding silicon lattice has been previously observed [ 15 ] and exploited to controllably etch arrays of silicon nanowires [ 16 ]. We have now found that it is possible to etch arrays of single-crystalline mesoporous silicon nanowires without the application of an external voltage.…”

“…The main difference between this and previous porous silicon syntheses is that the current flux used here to induce porosity is provided by continuous Ag + reduction from solution rather than an applied bias through electrical contacts. As previously described [ 15,16,18 ], reduction of metal atop the wafer oxidizes the silicon immediately surrounding nanometer-scale metal deposits on the wafer surface. This silicon dissolves in the HF solution and the metal particles etch pits down into the wafer, leaving behind the nanometer-scale pit walls between the particles which form the resulting nanowires.…”

Silicon Nanowires Substrates Fabrication for Ultra-Sensitive Surface Enhanced Raman Spectroscopy Sensors

“…[2][3][4][5]14] The cone shaped bundles creation can be partially correlated with the SiNWs elasticity and surface tension during drying process. [1] Furthermore, the van der Waals force influences the SiNWs tips [1] and stick them more as the etching time increases.…”

“…[1][2][3][4][5][6] Thanks to its high trace level detection and chemical fingerprint identification, SERS became one of the well accepted scientific tools which still looks for its development, novel applications and market. [7,8] SERS signal intensity depends on analyte -plasmons interaction i.e.…”

“…Therefore the choice of the appropriate substrate for a specific analyte and the analyte vicinity to metal NP is of the high importance. [9,10] Among non-colloidal substrates, silicon nanostructures such as porous silicon [6] and silicon nanowires [2][3][4][5]7] (SiNWs) draw attention owing to their low-cost fabrication and high SERS measurement reproducibility. SiNWs can be produced by chemical vapour deposition, laser ablation, vapour transport and condensation, molecular beam epitaxy, annealing of catalytic nanoclusters on silicon, solution growth, and catalytic etching.…”