A cost effectively method to fabricate nanopores in silicon by only using the conventional wet-etching technique is developed in this research. The main concept of the proposed method is a two-step etching process, including a premier double-sided wet etching and a succeeding track-etching. A special fixture is designed to hold the pre-etched silicon wafer inside it such that the track-etching ...

Controlled silicon structures on the micron to nanometer order have received much attention owing to their potential applications in various fields such as electrochemical, optoelectrical, and biological sciences. Although the techniques commonly used in fabricating nano-/microstructured silicon are conventional lithographic techniques using a resist mask with an optical, electron, or X-ray bea...

Based on previous theoretical and experimental results on the electrochemical etching of silicon in HF-based aqueous electrolytes, it is shown for the first time that silicon microstructures of various shapes and silicon microsystems of high complexity can be effectively fabricated in any research lab with sub-micrometer accuracy and high aspect ratio values (about 100). This is well beyond any...

A simple electrochemical fabrication of graphene nanomesh (GNM) via colloidal templating is reported for the first time. The process involves the arraying of polystyrene (PS) spheres onto a CVD-deposited graphene, electro-deposition of carbazole units, removal of the PS template and electrochemical oxidative etching. The GNM was characterized by scanning electron microscopy (SEM), atomic force ...

Nano-porous silicon were simply prepared from p-type single crystalline silicon wafer by electrochemical etching technique via exerting constant current density in two different HF-Ethanol and HF-Ethanol-H2O solutions. The mesoporous silicon layers were characterized by field emission scanning electron microscopy and scanning electron microscopy. The results demonstrate that the width of nano-p...

The controlled electrochemical etching at room temperature of deep (up to 200 μm) silicon microstructures with aspect ratio ranging from 5 to 100 and etching rates from 10 to 3 μm/min, respectively, is here reported and discussed. This allows silicon microfabrication technology entering a region in the parameter space etching-rate vs. aspect-ratio that was so far unreachable for silicon microst...

The etching of silicon has been studied by the scanning electrochemical microscope (SECM) technique. Etching has been accomplished in acidic fluoride solutions by electrogenerating a strong oxidant, i.e. bromine in this case, at an ultramicroelectrode which was held closely above a silicon (1 11) wafer. The parameters that affect the process and control the efficiency of the silicon etching wer...

An electrochemical etching technique has been developed that provides continuous control over the porosity of a porous silicon layer as a function of etching depth. Thin films with engineered porosity gradients, and thus a controllable gradient in the index of refraction, have been used to demonstrate broadband antireflection properties on silicon wafer and solar cell substrates. A simulation w...

Porous GaAs layers have been produced by electrochemical anodic etching of (100) heavily doped p-type GaAs substrate in HF solution. Scanning electron microscopy revealed the presence of etch pits ranging in size from 0.01 to 2 mm and they were strongly dependent on the electrochemical etching conditions. The etch pits chemical composition consists of O, Ga and As whereas the porous structure c...