Recent studies in nanopiezotronics have indicated that strained graphene may exhibit abnormal flexoelectric and piezoelectric properties. Similar assumptions have been made with regard to the properties of carbon nanotubes (CNTs), however, this has not so far been confirmed. This paper presents the results of our experimental studies confirming the occurrence of a surface piezoelectric effect in multi-walled CNTs under a non-uniform strain. Using atomic force microscopy, we demonstrated the piezoelectric response of multi-walled CNTs under compression and bending. The current generated by deforming an individual CNT was shown to be −24 nA. The value of the surface potential at the top of the bundle of strained CNTs varied from 268 mV to −110 mV, depending on strain type and magnitude. We showed that the maximum values of the current and the surface potential can be achieved when longitudinal strain predominates in a CNT. However, increasing the bending strain of CNTs does not lead to a significant increase in current and surface potential, due to the mutual compensation of piezoelectric charges concentrated on the CNT side walls. The results of the study offer a number of opportunities and challenges for further fundamental research on the piezoelectric properties of carbon nanotubes as well as for the development of advanced CNT-based nanopiezotronic devices.

The results of investigation of a memristor-matrix model on the basis of titanium-oxide nanoscale structures (ONSs) fabricated by methods of focused ion beams and atomic-force microscopy (AFM) are...

This paper reports the results of the influence of the energy of laser pulses during laser ablation on the morphology and electro-physical properties of LiNbO₃ nanocrystalline films. It is found that increasing laser pulse energy from 180 to 220 mJ results in the concentration of charge carriers in LiNbO₃ films decreasing from 8.6 × 10¹⁵ to 1.0 × 10¹³ cm⁻³, with the mobility of charge carriers increasing from 0.43 to 17.4 cm²/(V·s). In addition, experimental studies of sublayer material effects on the geometric parameters of carbon nanotubes (CNTs) are performed. It is found that the material of the lower electrode has a significant effect on the formation of CNTs. CNTs obtained at the same growth time on a sample with a Cr sublayer have a smaller diameter and a longer length compared to samples with a V sublayer. Based on the obtained results, the architecture of the energy nanogenerator is proposed. The current generated by the nanogenerator is 18 nA under mechanical stress of 600 nN. The obtained piezoelectric nanogenerator parameters are used to estimate the parameters of the hybrid-carbon-nanostructures-based piezoelectric energy converter. Obtained results are promising for the development of efficient energy converters for alternative energy devices based on lead-free ferroelectric films.

Radio-frequency switches manufactured by microelectromechanical systems technology are now widely used in aerospace systems and other mobile installations for various purposes. In these operating conditions, these devices are often exposed to intense mechanical environmental influences that have a strong impact on their operation. These negative effects can lead to unwanted short-circuit or open-circuit in the radio-frequency transmission line or to irreversible damage to structural elements. Such a violation in the operation of radio-frequency microelectromechanical switches leads to errors and improper functioning of the electronic equipment in which they are integrated. Thus, this review is devoted to the analysis of the origin of these negative intense mechanical effects of the environment, their classification, and analysis, as well as a review of methods to reduce or prevent their negative impact on the design of radio-frequency microelectromechanical switches.

The paper presents the results of experimental studies of the influence of the local anodic oxidation control parameters on the geometric parameters of oxide nanoscale structures (ONS) and profiled nanoscale structures (PNS) on the surface of epitaxial structures of silicon doped gallium arsenide with an impurity concentration of 5 × 10¹⁷ cm⁻³. X-ray photoelectron spectroscopy measurements showed that GaAs oxide consists of oxide phases Ga₂O₃ and As₂O₃, and the thickness of the Ga₂O₃ layer is 2–3 times greater than the thickness of As₂O₃ area—i.e., the oxidized GaAs region consists mainly of Ga₂O₃. The experimental studies of the influence of ONS thickness on the resistive switching effect were obtained. An increase in the ONS thickness from 0.8 ± 0.3 to 7.6 ± 0.6 nm leads to an increase in the switching voltage Uset from 2.8 ± 0.3 to 6.8 ± 0.9 V. The results can be used in the development of technological processes for the manufacturing of nano-electronic elements, such as ReRAM, as well as a high-efficiency quantum dot laser.

In this paper, we develop an integrated CMOS microwave energy converter for passive wireless microdevices. A modification of the voltage multiplier circuit, which allows implementing a device efficient in multiplication using standard CMOS technologies, is proposed. Compact models of multistage multipliers that take into account the voltage drops across nanoscale MOS transistors when operating in regions of weak and strong inversion are presented. The converter’s operation at 2.45 GHz is studied at various input power levels, including extremely low levels. It is established that, for the typical 90-nm CMOS technology, the device can operate at extremely low input power levels (less than –20 dBm), which allows wireless systems to operate both at a considerable distance from the base station and when collecting radio-frequency (RF) radiation energy from the environment.