Mechanical impulse enhancement in a microsystem based on nanoporous silicon combustion

Nanostructured porous silicon impregnated by solid state oxidizer has been studied in order to provide the mechanical impulse for jet-propulsion microsystems. The system with jet-propulsion motion on a silicon chip has been tested for impulse measurements. The silicon chip has been fastened on a carrying platform through an elastic spacer. The elastic spacer promotes the combustion and prevents from explosion of porous silicon fast oxidation. It is shown that such a microsystem gains the impulse up to 200-220 mN•s

Local electrochemical deposition of Ni into vertical vias in Si/SiO2 substrate

Ni electrochemical deposition into a matrix of various diameters (500–2000 nm) vertical vias in Si/SiO2 substrates with a barrier layer at the vias’ bottom has been investigated. Morphological study of Ni deposits in the vias showed they are deposited directly on the surface of the barrier layer. Repeatability and stability in combination with a homogeneous structure and 70% filling degree of vias determine the prospects of the Si/SiO2/Ni system as a basic element for the creation of three-dimensional micro-, nanostructures, and 3D assembly of IC crystals

Quantum drift-diffusion models for dual-gate field-effect transistors based on mono- and bilayer graphene

At present, a great deal of interest is observed in devices based on two-dimentional (2D) materials, especially graphene, in the field of micro- and nanoelectronics. Graphene has robust hoheycomb lattice structure and unique properties such as ambipolarity, high carrier mobility, high conductivity. Nevertheless the properties of mono- and bilayer graphene are different

Simulation of various nanoelectronic devices based on 2D materials

The development of field-effect transistors (FETs), resonant- tunneling diodes (RTDs), vertical heterostructures and other device structures on the basis of 2D materials is one of the important tasks for producing a new element base for micro and nanoelectronics

3D Silicon Photonic Structures Based on Avalanche LED with Interconnections through Optical Interposer

Design and manufacturing technology of 3-D silicon photonic structures with optical interconnections through microchannel vias interposers were developed. Silicon chips placed over each other were separated by the silicon microchannel vias interposer served as a light waveguide. Light emitting diodes and photodiodes were formed at the inner surfaces of silicon chips from nanostructured silicon clusters embedded into alumina matrix. The developed structure is characterized by the current conversion efficiency of 0.1 % and can operate in the GHz frequency range

Plasma assisted-MBE of GaN and AlN on graphene buffer layers

The possibility of using chemical vapor deposition (CVD) graphene as a 2D buffer layer for epitaxial growth of III-nitrides by plasma assisted-MBE on amorphous substrates (SiO2 prepared by thermal oxidation of Si wafer) was investigated. The comparative study of graphene-coated parts of the wafers and the parts without graphene was carried out by scanning electron microscopy and X-ray diffractometry. It was shown that epitaxial GaN and AlN films with close to 2D surface morphology can be obtained by plasma assisted-MBE on amorphous SiO2 substrates with a multilayer graphene buffer using the HT AlN nucleation layer

Study of the Thermal Stability of Copper Contact Junctions in Si/SiO2 Substrates

The results of a comprehensive study of the structural- morphological and thermodynamic characteristics of the electrochemical precipitation of Cu in transition holes with a barrier layer of TiN in Si/SiO2 substrates by scanning electron microscopy (SEM) and differential thermal analysis (DTA) are presented. The temperature range that determines the heat resistance of copper (up to 750°C) and the temperature range (up to 886°C) that determines the thermal stability of the composite as a whole, as well as the ability to maintain the chemical composition and ordered structure at elevated temperatures, are found

Potent E. coli M‑17 Growth Inhibition by Ultrasonically Complexed Acetylsalicylic Acid−ZnO−Graphene Oxide Nanoparticles

A single-step ultrasonic method (20 kHz) is demonstrated for the complexation of acetylsalicylic acid (ASA)−ZnO− graphene oxide (GO) nanoparticles with an average size of <70 nm in aqueous solution. ASA−ZnO−GO more e ffi ciently inhibits the growth of probiotic Escherichia coli strain M-17 and exhibits enhanced antioxidant properties than free ASA and ASA−ZnO in neutralization of hydroxyl radicals in the electro-Fenton process. This improved function of ASA in the ASA −ZnO GO can be attributed to the well-de fi ned cone-shaped morphology, the surface structure containing hydroxyl and carboxylate groups of ZnO−GO nanoparticles, which facilitated the complexation with ASA

Properties of Nitrogen/Silicon Doped Vertically Oriented Graphene Produced by ICP CVD Roll-to-Roll Technology

Simultaneous mass production of high quality vertically oriented graphene nanostructures and doping them by using an inductively coupled plasma chemical vapor deposition (ICP CVD) is a technological problem because little is understood about their growth mechanism over enlarged surfaces. We introduce a new method that combines the ICP CVD with roll-to-roll technology to enable the in-situ preparation of vertically oriented graphene by using propane as a precursor gas and nitrogen or silicon as dopants. This new technology enables preparation of vertically oriented graphene with distinct morphology and composition on a moving copper foil substrate at a lower cost. The technological parameters such as deposition time (1–30 min), gas partial pressure, composition of the gas mixture (propane, argon, nitrogen or silane), heating treatment (1–60 min) and temperature (350–500 °C) were varied to reveal the nanostructure growth, the evolution of its morphology and heteroatom’s intercalation by nitrogen or silicon. Unique nanostructures were examined by FE-SEM microscopy, Raman spectroscopy and energy dispersive X-Ray scattering techniques. The undoped and nitrogen- or silicon-doped nanostructures can be prepared with the full area coverage of the copper substrate on industrially manufactured surface defects. Longer deposition time (30 min, 450 °C) causes carbon amorphization and an increased fraction of sp3-hybridized carbon, leading to enlargement of vertically oriented carbonaceous nanostructures and growth of pillars

Metallization of Vias in Silicon Wafers to Produce Three-Dimensional Microstructures

The processes of electrochemical deposition into a matrix of vertical vias of different diameters (500–2000 nm) in Si/SiO2 substrates with a TiN barrier layer at the bottom of the holes are studied. Morpho- logical studies of the metal in the holes show that the structure of copper clusters is rather uniform and is formed from crystallites of ~30 to 50 nm. Repeatability and stability with a homogeneous structure and with holes filled 100% by Cu determine the prospect of using the Si/SiO2/Cu system as a basic element for creating three-dimensional micro- and nanostructures, as well as for the 3D assembly of IC crystals