Porous CdSe layers have been produced by anodic etching of crystalline substrates in a HCl solution. Anodization under in situ UV illumination resulted in the formation of uniformly distributed parallel pores with a diameter of 30 nm, stretching perpendicularly to the initial surface. At the same time, pronounced nonuniformities in the spatial distribution of pores were evidenced in samples sub...

objectives: this study aimed to determine the effect of surface treatments such as tooth reduction and extending the etching time on microtensile bond strength (µtbs) of composite resin to normal and fluorotic enamel after microabrasion. materials and methods: fifty non-carious anterior teeth were classified into two groups of normal and fluorotic (n=25) using thylstrup and fejerskov index (tfi...

Sub-micrometre single crystal diamond membranes are of huge importance for next generation optical, quantum and electronic device applications. Electrochemical etching has proven a critical step in the production such membranes. Etching is used to selectively remove very thin layer sub-surface sp2 carbon, prepared by ion implantation bulk diamond, releasing membrane. Due nanosized dimensions, t...

The study of an innovative fluoropolymer masking layer for silicon anodization is proposed. Due to its high chemical resistance to hydrofluoric acid even under anodic bias, this thin film deposited by plasma has allowed the formation of deep porous silicon regions patterned on the silicon wafer. Unlike most of other masks, fluoropolymer removal after electrochemical etching is rapid and does no...

We report a high-throughput procedure for lithographically processing one-dimensional nanowires. This procedure, termed on-wire lithography, combines advances in template-directed synthesis of nanowires with electrochemical deposition and wet-chemical etching and allows routine fabrication of face-to-face disk arrays and gap structures in the range of five to several hundred nanometers. We stud...

Photoacoustic Spectroscopy (PAS) has been performed on Porous Silicon Layers (PSL) obtained by chemical and electrochemical etching of crystalline Silicon. In the investigated energy range (2.0eV-4.7eV) the samples behave as optically opaque and show strong light scattering properties so to prevent the application of standard reflectivityftrasmission techniques. PAS proves suitable in studying ...

porous silicon layers have been prepared from n-type silicon wafers of (100) orientation. sem, ftir and pl have been used to characterize the morphological and optical properties of porous silicon. the influence of varying etching time in the anodizing solution, on structural and optical properties of porous silicon has been investigated. it is observed that pore size increases with etching tim...

The finite-element method (FEM) (Comsol RF Module) has been employed for modal analyses of porous silicon (PSi) waveguides composed of a guiding layer of low porosity (high refractive index) on a cladding layer with higher porosity (lower refractive index). These can be made by switching the current density from a lower to a higher value during the electrochemical etching process. The applicabi...

Nanoporous silicon optical waveguides, which serve as the basic foundation for porous silicon based biochemical sensors, have been fabricated by electrochemical etching and laser local oxidation. By optimizing the porous silicon layers, laser writing power and speed, acceptable optical losses have been achieved. Loss mechanisms include scattering, intrinsic absorption, coupling loss at the fibe...