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...

We present analytical and computational models used to investigate the dependence of etch resolution on pulse duration, tool radius, and etched feature aspect ratio in electrochemical machining with ultrashort voltage pulses. Our results predict that, for the high aspect ratio system in which the effect of trench top and bottom edges can be ignored, the increase of etch resolution with pulse le...

We fabricate and characterize carbon-fiber tips for their use in combined scanning tunneling and force microscopy based on piezoelectric quartz tuning fork force sensors. An electrochemical fabrication procedure to etch the tips is used to yield reproducible sub-100-nm apex. We also study electron transport through single-molecule junctions formed by a single octanethiol molecule bonded by the ...

Titanium is a promising new material system for the bulk micromachining of microelectromechanical MEMS devices. Titaniumbased MEMS have the potential to be used for a number of applications, including those which require high fracture toughness or biocompatibility. The bulk titanium etch rate, TiO2 mask etch rate, and surface roughness in an inductively coupled plasma ICP as a function of vario...

A wet etch process that produces smooth sidewalls aligned with the m-plane ({1!100}) crystal facets of Ga-polar GaN grown on sapphire is demonstrated by combining photo-electrochemical (PEC) treatment with a postprocessing wet etch step. This novel process results in faceted and extremely smooth vertical etched sidewalls. This two-step process consists of a PEC treatment to define the geometry ...

An experimental setup has been developed for successive photo-electrochemical etch and EIS measurement of semiconductor samples. Furthermore an algorithm based on electrochemical capacitance-voltage (ECV) has been developed for calculating dopant profile based on the measurements by developed setup. Phosphorous diffusion profile in p-type silicon was estimated by employing developed setup and a...

Using the network etch rate function model, the anisotropic etch rate of p-type single crystal silicon was characterised in terms of microscopic properties including step velocity, step and terrace roughening. The anisotropic etch rate data needed have been obtained using a combination of 2 wagon wheel patterns on different substrate and 1 offset trench pattern. Using this procedure the influen...

Amorphous-like Ni-Fe-S ultrathin nanosheets by oxygen incorporation and electrochemical tuning show excellent OER activity at high current densities. Such excellent performance could be attributed to the unique 3D porous configuration composed of amorphous-like ultrathin nanosheets with much more active sites and improved conductivity, as well as the proper electronic structure benefiting from ...

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...