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Arrays of vertically aligned silicon nanowires were fabricated by cryogenic dry etching. The post-processing technology was developed to full coating of arrays of NWs by SU-8 and release the top side of SiNWs. The Schottky diodes were fabricated on arrays of SiNWs with and without SU-8 by gold evaporation. The cryogenic dry etching leads to defect formation with Ea=0.28 eV and concentration lower 5⋅1012 cm−3 in near-surface area in silicon, and no defect are detected in bulk silicon. However, oxygen plasma treatment used to release top side of SiNWs leads to increase of its concentration by two order and formation of defect with Ea=0.39 eV, σ = 1⋅10−16 cm2 and a concentration of 5⋅1014 cm−3 in a bulk of SiNWs deeper than 1 μm.

This work is devoted to the study of the deposition of a-Si:H by the PECVD method in continuous and pulsed regime on test structures in the form of trenches with a high aspect ratio. The thicknesses of the layers obtained in these modes were investigated by the method of scanning electron microscopy. It was shown that the layers obtained in the pulsed mode, as compared with the continuous one, have better conformity.

Carbon monoxide and ammonia are inorganic agents found both in nature and in the human body, which is of great interest for modern sensing. First, in concentrations of the order of 1 ppm agents are produced by human and can be markers of changes in human health. Second, at concentrations of the order of 100 ppm, carbon monoxide and ammonia are toxic and hazardous. This work is aimed at fabrication and study of precise, technological and relatively cheap sensors compatible with a gas and liquid medium for CO and NH3 detection, respectively.

This article is devoted to the formation and study of the properties of amorphous gallium phosphide layers obtained by plasma-chemical deposition at a temperature of 250 °C. The optical and structural properties of the obtained layers on fused silica and silicon substrates were investigated. The possibility of the formation of a homogeneous amorphous gallium phosphide with a smooth surface at a low temperature and low power of RF plasma was shown.

Carbon monoxide and ammonia are inorganic agents found both in nature and in the human body, which is of great interest for modern sensing. The work is aimed at fabrication and study of precise, technological and relatively cheap multi-environment sensors based on Si nanowires possessing high surface area compatible with a gas and liquid medium for CO and NH3 detection, respectively. We demonstrate the potential of the approach for detection of both ammonia and CO at concentrations as low as 10ppm. The effects of the adsorbates from water and air are discussed.

Arrays of silicon nanowires were fabricated by dry etching in the ICP mode in a mixture of SF6/O2 gases at a temperature of-140 °C. Defects located near the wafer surface with E a =0.30 eV, σ=(1–10)×10−14 cm2 and E a =0.68–0.74 eV, σ=1×10−15 cm2 were detected by admittance spectroscopy and deep-level transient spectroscopy. An increase in the dry etching time from 3.5 min (for the 1st sample) to 4.5 min (for the 2nd sample) leads to an rise of their concentration, but additional stage of wet etching in 4% KOH during 30 s leads to a vanish of the response from the first sample (N T ˂1011 cm−3), while for the second sample the defect concentration becomes in two times lower.

The features of the formation of a SiO2 hard mask using dry etching and nanosphere lithography are considered in the paper. A series of experiments was carried out using a variation of plasma etching parameters such as ICP and RF power, pressure as well as a substrate temperature. As a result, optimal parameters were found to obtain both good selectivity and high etching rate.

In this paper, we study the effect of the height and diameter of vertically aligned silicon structures on their optical properties. Structures with different geometry were formed using nanosphere lithography and dry etching. Nanosphere lithography was realized with 0.9 and 2 μm latex spheres. The etching process was carried out through a formed mask (template) composed of 0.9 and 2 μm latex spheres, respectively. The diameter of the spheres and the etching time determined the size of the formed structures and their optical properties. A significant reduction of the total reflection with height as well as blue shift of the minimum with diameter decrease were observed.