0000000000244710
AUTHOR
Raitis Sondors
CuO un Bi2Se3 nanovadu ar kontrolētām īpašībām iegūšana pielietojumiem nanoierīču aktīvajos elementos
Pusvadītāju nanovadi ir perspektīvi materiāli pielietojumiem nanoelektromehāniskās (NEM) ierīcēs. Lai nanovadi būtu piemēroti industriāliem pielietojumiem, nepieciešams izstrādāt tādas sintēzes metodes, kas nodrošinātu paredzamu iznākumu, morfoloģiju, elektriskās un mehāniskās īpašības sintezētajiem nanovadiem. Lai nodrošinātu NEM slēdžu darbību ekstrēmos apstākļos, nepieciešams iegūt plašā temperatūru diapazonā pielietojamus nanovadus. Pielietojumiem istabas temperatūrā tika pētīti CuO un ar Sn dopēti Ge nanovadi. CuO nanovadi tika sintezēti ar pārveidotu termiskās oksidācijas metodi. Tika izpētīts, kā, papildinot termisko oksidāciju ar elektrisko lauku un ūdens tvaiku klātbūtni, iespējams…
Dielectrophoretic alignment and electrical characterization of CuO nanowire-based systems
Abstract Dielectrophoresis is used to assemble nanowires between metallic electrodes to form scalable functional interconnects. The dielectrophoresis parameters are investigated for semiconductor copper oxide (CuO) nanowires that are desirable for energy conversion and storage, gas sensors and nanoelectromechanical systems. Experimental yields of multiple- and single-nanowire interconnects are explored at dielectrophoresis frequencies from 500 Hz to 500 kHz. The electrical properties of nanowire-electrode physical contact interfaces formed by dielectrophoresis, metal deposition, and dry mechanical transfer are investigated. The electrical transport mechanism in these interconnects is determ…
Fabrication and Characterization of Double- and Single-Clamped CuO Nanowire Based Nanoelectromechanical Switches
Electrostatically actuated nanoelectromechanical (NEM) switches hold promise for operation with sharply defined ON/OFF states, high ON/OFF current ratio, low OFF state power consumption, and a compact design. The present challenge for the development of nanoelectromechanical system (NEMS) technology is fabrication of single nanowire based NEM switches. In this work, we demonstrate the first application of CuO nanowires as NEM switch active elements. We develop bottom-up and top-down approaches for NEM switch fabrication, such as CuO nanowire synthesis, lithography, etching, dielectrophoretic alignment of nanowires on electrodes, and nanomanipulations for building devices that are suitable f…
Cryogenic nanoelectromechanical switch enabled by Bi2Se3 nanoribbons
Abstract Nanoelectromechanical (NEM) switches are potential candidates for memory and logic devices for low standby-current and harsh environment applications. Cryogenic operation of these devices would allow to use them, e.g., in space probes and in conjunction with quantum computers. Herein, it is demonstrated that cryogenic application requirements such as good flexibility and conductivity are satisfied by using Bi2Se3 nanoribbons as active elements in NEM switches. Experimental proof of principle NEM switching at temperatures as low as 5 K is achieved in volatile and non-volatile reversible regimes, exhibiting distinct ON and OFF states, backed by theoretical modelling. The results open…
Pusvadītāju nanovadu īpašības un pielietojumi nanoelektromehāniskās sistēmās
Nanovadi ir viendimensionāli nanomateriāli ar rādiusu nanometros un garumu mikrometros. Nanovadi ir vēlamas komponentes nanoelektromehāniskās (NEM) ierīcēs, piemēram, slēdžos. Šajās ierīces nanovadi kalpo kā aktīvie elementi, kas, mehāniski pārslēdzoties, spēj pārslēgt elektriskās ķēdes, tāpēc ir svarīgas nanovadu mehāniskās un elektriskās īpašības. Darbā tika pētīti CuO, GeSn un Bi2Se3 nanovadi ar mērķi tos pielietot NEM ierīcēs. Tika veikta CuO nanovadu sintēze ar termiskās oksidācijas metodi. Izanalizēta dažādu sintēzes parametru, piemēram, ūdens tvaika un elektriskā lauka, ietekme uz nanovadu morfoloģiju. Tika izpētītas CuO nanovadu mehāniskās īpašības. GeSn nanovadu Junga modulis tika …
High-Yield Growth and Tunable Morphology of Bi2Se3 Nanoribbons Synthesized on Thermally Dewetted Au
The yield and morphology (length, width, thickness) of stoichiometric Bi2Se3 nanoribbons grown by physical vapor deposition is studied as a function of the diameters and areal number density of the Au catalyst nanoparticles of mean diameters 8–150 nm formed by dewetting Au layers of thicknesses 1.5–16 nm. The highest yield of the Bi2Se3 nanoribbons is reached when synthesized on dewetted 3 nm thick Au layer (mean diameter of Au nanoparticles ~10 nm) and exceeds the nanoribbon yield obtained in catalyst-free synthesis by almost 50 times. The mean lengths and thicknesses of the Bi2Se3 nanoribbons are directly proportional to the mean diameters of Au catalyst nanoparticles. In contrast, the me…
Investigating the mechanical properties of GeSn nanowires.
Germanium tin (GeSn) has been proposed as a promising material for electronic and optical applications due to the formation of a direct band-gap at a Sn content >7 at%. Furthermore, the ability to manipulate the properties of GeSn at the nanoscale will further permit the realisation of advanced mechanical devices. Here we report for the first time the mechanical properties of GeSn nanowires (7.1-9.7 at% Sn) and assess their suitability as nanoelectromechanical (NEM) switches. Electron microscopy analysis showed the nanowires to be single crystalline, with surfaces covered by a thin native amorphous oxide layer. Mechanical resonance and bending tests at different boundary conditions were use…
Size Distribution, Mechanical and Electrical Properties of CuO Nanowires Grown by Modified Thermal Oxidation Methods
Size distribution, Young&rsquo
Nanowires for NEMS Switches
Nanoelectromechanical systems (NEMS) are a promising novel technology for operation in extreme conditions (e.g. high temperature and radiation levels), where complementary semiconductor technology devices might fail due to electronic instability. An example for a NEMS device is a nanowire-based switch, which employs mechanical deflection of a nanowire to open and close an electrical circuit. To date, assembly and operation of individual nanowire based NEMS switches have been successfully demonstrated at laboratory level, but their further technological development remains a challenge. This chapter gives an insight into the current advances in applications of nanowires for NEMS switches. Syn…