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

Mössbauer spectroscopy investigation of magnetic nanoparticles incorporated into carbon nanotubes obtained by the injection CVD method

This paper is devoted to the investigation of phase composition of the magnetic filler located inside multi-wall carbon nanotubes (CNTs) using Mössbauer spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). CNTs were obtained by the injection CVD method using ferrocenexylene solution under various conditions (i.e., the ferrocene concentration cx (1%, 5%, and 10%), slow or fast cooling down rates of the synthesis reactor, temperature in the reaction zone during synthesis), which can influence the magnetic properties of CNTs owing to different contribution of Fe-containing phases. SEM and TEM methods were applied to investigate morphology and structure of the synthesized material. It was shown that Fe₃C phase formation is favorable at high content of the catalyst in the feeding solution (10%), relatively low temperatures (775 ºC) during CNTs synthesis, as well as long duration of the CNTs growth process (5 min). The cooling rate of the reactor after CNTs synthesis was not crucial to iron phase contribution in our experiments

Composite nanostructure of vertically aligned carbon nanotube array and planar graphite layer obtained by the injection CVD method

The carbon nanostructure composed of an array of vertically aligned carbon nanotubes (CNTs) and a planar graphite layer (PGL) located at the top of the array has been obtained by the injection chemical vapor deposition method, realized using high temperature catalytic pyrolysis of xylene-ferrocene mixture. The carbon nature of the planar layer was identified using Auger electron spectroscopy. Scanning electron microscopy analysis enabled to ascertain peculiarities of CNT-PGL nanostructure morphology, in particular, the internal layer-built structure of PGL and its links with the underlying CNT array. The mechanism of CNT-PGL nanostructure formation was considered

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

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

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