Seebeck coefficient of silicon nanowire forests doped by thermal diffusion

• Shaimaa Elyamny,
• Elisabetta Dimaggio and
• Giovanni Pennelli

Beilstein J. Nanotechnol. 2020, 11, 1707–1713, doi:10.3762/bjnano.11.153

• metal-assisted etching technique. After fabrication, a thermal diffusion process is used for doping the nanowire forest with phosphorous. A suitable experimental technique has been developed for the measurement of the Seebeck coefficient under static conditions, and results are reported for different

• thermoelectric material is the development of techniques for the low-cost fabrication and interconnection of a large number of nanostructures to generate a significant amount of power. Metal-assisted chemical etching (MACE) [11][12][13][14] of silicon is very promising because it gives the opportunity to

• on one-pot metal-assisted chemical etching (MACE) [22] (Figure 1). Silicon chips of roughly 1 × 1 cm2 have been cut from n-doped (phosphorous) commercial silicon ⟨100⟩ wafers with a nominal resistivity of 10 Ω·cm (nominal doping concentration 1015 cm−3). The chips, mounted on a custom-made apparatus

Out-of-plane surface patterning by subsurface processing of polymer substrates with focused ion beams

• Serguei Chiriaev,
• Luciana Tavares,
• Vadzim Adashkevich,
• Arkadiusz J. Goszczak and
• Horst-Günter Rubahn

Beilstein J. Nanotechnol. 2020, 11, 1693–1703, doi:10.3762/bjnano.11.151

• -assisted chemical etching and ion-beam-assisted chemical vapor deposition [1][2][3]. All these methods are based on processes that either add or remove atoms on the surface or in the subsurface atomic layers. The ion beams deposit their energy and, therefore, affect the structure and properties of

• ][16]. It has also been demonstrated that it acts as a type of ion-beam resist in the fabrication of micro- and nanopore membranes and templates for nanowires by chemical etching of through-holes along ion tracks produced by high-energy ions [17][18]. In contrast to PMMA and PC polymers, PDMS is a

A self-powered, flexible ultra-thin Si/ZnO nanowire photodetector as full-spectrum optical sensor and pyroelectric nanogenerator

• Liang Chen,
• Jianqi Dong,
• Miao He and
• Xingfu Wang

Beilstein J. Nanotechnol. 2020, 11, 1623–1630, doi:10.3762/bjnano.11.145

• process of device preparation is shown in the Experimental section. The 45 μm ultrathin p-Si layer is obtained by isotropic chemical etching to realize a flexible device. Importantly, a previous study has shown that the performance of PDs (regarding, e.g., transient current and response speed) of PDs is

• full-spectrum optical sensing or optical communication. Powering external circuits as a PENG In structure design of the device, ultra-thin (45 μm) p-Si is prepared by isotropic chemical etching to fabricate flexible electronic devices and enhance the performance of the PDs. The structure diagram of a

• etching. More specifically, a 500 μm p-type high conductivity Si substrate was dipped into potassium hydrate (KOH) solution with a concentration of 50% at 130 °C for 6–8 h. Then, the obtained 45 μm p-Si was washed with acetone, isopropanol, and deionized water. Secondly, a thin ZnO seed layer was

PTCDA adsorption on CaF₂ thin films

• Philipp Rahe

Beilstein J. Nanotechnol. 2020, 11, 1615–1622, doi:10.3762/bjnano.11.144

• dissociated fluorine atoms mostly desorb from the surface, likely in the form of SixF molecules [28][29]. Thicker CaF2 layers can then be grown stoichiometrically on the interface layer by successive CaF2 deposition. The CaF1/Si(111) surface has a (1 × 1) termination after etching the Si(111)-(7 × 7

Walking energy harvesting and self-powered tracking system based on triboelectric nanogenerators

• Mingliang Yao,
• Guangzhong Xie,
• Qichen Gong and
• Yuanjie Su

Beilstein J. Nanotechnol. 2020, 11, 1590–1595, doi:10.3762/bjnano.11.141

• transportation control, and for environmental monitoring. Experimental Surface modification of a PTFE film The surface modification of a PTFE film was performed in a similar manner as described previously [34]. Deep reactive ion etching was employed to construct PTFE nanowires aligned on the surface. Isopropyl

• and deionized water were used to clean 50 μm thick PTFE films, which were then dried with nitrogen. During the etching process, DC sputtering was used on the surface of the PTFE film as a mask to deposit Au particles for 45 s. Next, a gas mixture containing O2, CF4, and Ar was introduced to the

• inductively coupled plasma chamber, at corresponding flow rates of 10.0, 30.0, and 15.0 sccm, respectively. The nanowire structure was obtained on the surface by etching the PTFE film for 15 s. The high-density plasma was generated by a 500 W power source while the plasma ions were triggered by another 160 W

Fabrication of nano/microstructures for SERS substrates using an electrochemical method

• Jingran Zhang,
• Tianqi Jia,
• Xiaoping Li,
• Junjie Yang,
• Zhengkai Li,
• Guangfeng Shi,
• Xinming Zhang and
• Zuobin Wang

Beilstein J. Nanotechnol. 2020, 11, 1568–1576, doi:10.3762/bjnano.11.139

• machined by using lithography-based method [15][16][17][18][19][20]. Additionally, nanostructures are also fabricated by hybrid lithography [21][22][23][24][25][26] methods combined with dry etching or wet etching. For example, the commercial Klarite substrate [21][22][23] machined by electron beam

• lithography (EBL) and wet etching consists of 1 μm deep square-based pyramidal pits in the silicon surface. A rhodamine solution (10−4 mol·L−1) is then detected using the Klarite substrate. Candeloro et al. [24] employed EBL and reactive ion etching to machine nanoholes of 400 nm diameter and 50 nm depth

• and reactive ion etching methods [25]. The Raman intensities of R6G and 4-mercaptopyridine molecules were measured by using different substrates. In addition, the Raman intensity of R6G on the pyramid structures was higher than that of R6G on the other structures in the experiment, and the enhancement

Optically and electrically driven nanoantennas

• Monika Fleischer,
• Dai Zhang and
• Alfred J. Meixner

Beilstein J. Nanotechnol. 2020, 11, 1542–1545, doi:10.3762/bjnano.11.136

• are on the lookout for nanotips that can be prepared fast and with reproducible properties, and at the same time, aim for ever higher field enhancement and localization to improve the sensitivity and spatial resolution of the TERS information. In [47], an earlier protocol for etching thin gold wires

Wafer-level integration of self-aligned high aspect ratio silicon 3D structures using the MACE method with Au, Pd, Pt, Cu, and Ir

• Mathias Franz,
• Romy Junghans,
• Paul Schmitt,
• Adriana Szeghalmi and
• Stefan E. Schulz

Beilstein J. Nanotechnol. 2020, 11, 1439–1449, doi:10.3762/bjnano.11.128

• Abstract The wafer-level integration of high aspect ratio silicon nanostructures is an essential part of the fabrication of nanodevices. Metal-assisted chemical etching (MACE) is a promising low-cost and high-volume technique for the generation of vertically aligned silicon nanowires. Noble metal

• nanoparticles were used to locally etch the silicon substrate. This work demonstrates a bottom-up self-assembly approach for noble metal nanoparticle formation and the subsequent silicon wet etching. The macroscopic wafer patterning has been done by using a poly(methyl methacrylate) masking layer. Different

• with a reflectance below 0.3%. The demonstrated technology can be integrated into common fabrication processes for microelectromechanical systems. Keywords: black silicon; bottom-up; metal-assisted chemical etching (MACE); nanowires; wafer-level integration; Introduction Silicon nanostructures

One-step synthesis of carbon-supported electrocatalysts

• Sebastian Tigges,
• Nicolas Wöhrl,
• Ivan Radev,
• Ulrich Hagemann,
• Markus Heidelmann,
• Thai Binh Nguyen,
• Stanislav Gorelkov,
• Stephan Schulz and
• Axel Lorke

Beilstein J. Nanotechnol. 2020, 11, 1419–1431, doi:10.3762/bjnano.11.126

• . [28] and Suzuki and coworkers [29]. The reduction of the density of the CNWs results from the etching of the CNWs at the initial nucleation step by atomic hydrogen, effectively reducing the nucleation sites. Increasing the H2 concentration in the plasma finally results in the deposition of an

• addition of hydrogen, the Pt loading of the catalyst also increases. This results from the etching effect of hydrogen on carbon structures, while Pt is not etched chemically. An increase in substrate temperature reduces the platinum loading in the resulting hybrid material (P10 vs P12 and P9 vs P11; Table

Analysis of catalyst surface wetting: the early stage of epitaxial germanium nanowire growth

• Owen C. Ernst,
• Felix Lange,
• David Uebel,
• Thomas Teubner and
• Torsten Boeck

Beilstein J. Nanotechnol. 2020, 11, 1371–1380, doi:10.3762/bjnano.11.121

• were used for these experiments: The first substrate was single-crystalline Si(111) wafers of 25 × 25 × 0.525 mm3 in size. These wafers where chemically cleaned by the conventional Radio Corporation of America (RCA) etching processes, known as RCA 1 and RCA 2, to get hydrophilic silicon surfaces

Ultrasensitive detection of cadmium ions using a microcantilever-based piezoresistive sensor for groundwater

• Dinesh Rotake,
• Anand Darji and
• Nitin Kale

Beilstein J. Nanotechnol. 2020, 11, 1242–1253, doi:10.3762/bjnano.11.108

• . It was calibrated using atomic force microscopy (AFM) [40]. The process begins with thermal oxidation of Si at 1000 °C using an oxidation furnace to obtain a thermally grown SiO2 layer followed by masking and etching to get the desired pattern. The polysilicon is deposited in a low-pressure chemical

Revealing the local crystallinity of single silicon core–shell nanowires using tip-enhanced Raman spectroscopy

• Marius van den Berg,
• Ardeshir Moeinian,
• Arne Kobald,
• Yu-Ting Chen,
• Anke Horneber,
• Steffen Strehle,
• Alfred J. Meixner and
• Dai Zhang

Beilstein J. Nanotechnol. 2020, 11, 1147–1156, doi:10.3762/bjnano.11.99

• antenna. This nanoantenna is typically made by chemical etching of a thin Ag or Au wire or by evaporating a Ag or Au thin film on AFM tips. The tip works like an optical antenna when it is brought as close as a few nanometers to the sample surface and when it is illuminated with a tightly focused laser

Electrochemical nanostructuring of (111) oriented GaAs crystals: from porous structures to nanowires

• Elena I. Monaico,
• Eduard V. Monaico,
• Veaceslav V. Ursaki,
• Shashank Honnali,
• Vitalie Postolache,
• Karin Leistner,
• Kornelius Nielsch and
• Ion M. Tiginyanu

Beilstein J. Nanotechnol. 2020, 11, 966–975, doi:10.3762/bjnano.11.81

• , Chisinau MD-2001, Republic of Moldova Leibniz IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany 10.3762/bjnano.11.81 Abstract A comparative study of the anodization processes occurring at the GaAs(111)A and GaAs(111)B surfaces exposed to electrochemical etching in neutral NaCl and acidic HNO3 aqueous

• with diameters of about 50 nm and oriented normally to a InP wafer, i.e., along the crystallographic [100] orientation, was obtained after anodic etching at elevated applied voltages [14]. High-aspect-ratio GaAs pillar arrays with triangular cross section were prepared by combining colloidal crystal

• templating, anisotropic chemical etching, localized anodic etching, and isotropic anodic oxidation [15][16]. However, this is a complex multistep technology. A more simple and cost-effective technology was applied for obtaining triangular GaAs nanowires through electrochemical etching of GaAs(100) surfaces

Atomic layer deposition for efficient oxygen evolution reaction at Pt/Ir catalyst layers

• Stefanie Schlicht,
• Korcan Percin,
• Stefanie Kriescher,
• André Hofer,
• Claudia Weidlich,
• Matthias Wessling and
• Julien Bachmann

Beilstein J. Nanotechnol. 2020, 11, 952–959, doi:10.3762/bjnano.11.79

• etching. The surface roughness has increased, thereby increasing the specific surface area. The acid treatment also generates a homogeneously thin and stable TiO2 layer, which provides corrosion resistance while maintaining low transfer coefficients [24]. After coating with the catalyst layer (Figure 1c

• the coating of commercial titanium felts, the surface area of which is enhanced by either thermal acid etching or electrochemical “anodization”. Platinum and iridium catalysts are deposited either by dip-coating/thermal decomposition from a solution of noble metal salts or by atomic layer deposition

Integrated photonics multi-waveguide devices for optical trapping and Raman spectroscopy: design, fabrication and performance demonstration

• Gyllion B. Loozen,
• Arnica Karuna,
• Mohammad M. R. Fanood,
• Erik Schreuder and
• Jacob Caro

Beilstein J. Nanotechnol. 2020, 11, 829–842, doi:10.3762/bjnano.11.68

• waveguides is completely decoupled from the silicon substrate. Then, a 100 nm thick layer of Si3N4 is deposited using low pressure chemical vapor deposition (LPCVD, Figure 5b). This layer is patterned using optical lithography and reactive ion etching (RIE) in a fluorine-based plasma, which is followed by

• results in layer cracking due to stress after deposition. Then, a 3 µm thick layer of SiO2 is deposited by LPCVD, which acts as the top cladding for the detection waveguides and as a protection layer (Figure 5h). The final in-line step is the etching of the cylindrical microbath centered at each chip

• (compare Figure 4b) using deep reactive ion etching (DRIE). This is a critical step, since the etch goes 14.3 µm deep down to the substrate, through all the device layers, including the waveguide circuitry at two levels. The etch is highly anisotropic and produces smooth walls of the microbath and thus

A set of empirical equations describing the observed colours of metal–anodic aluminium oxide–Al nanostructures

• Cristina V. Manzano,
• Jakob J. Schwiedrzik,
• Gerhard Bürki,
• Laszlo Pethö,
• Johann Michler and
• Laetitia Philippe

Beilstein J. Nanotechnol. 2020, 11, 798–806, doi:10.3762/bjnano.11.64

• and thickness) and the porosity of the films was changed by applying different chemical etching times (from 2 to 8 min) using a 5 wt % H3PO4 solution at 35 °C. In order to obtain different colours of the nanostructures, an 8 nm thin film of chromium was deposited on top of the AAO films using an

• note that the AAO–Al nanostructures are exactly the same for the study. In order to obtain nanostructures with different Au thickness, a Au layer was deposited and subsequently removed using an aqueous etching solution of I2 and KI before the deposition of the next Au layer with different thickness

Hexagonal boron nitride: a review of the emerging material platform for single-photon sources and the spin–photon interface

• Stefania Castelletto,
• Faraz A. Inam,
• Shin-ichiro Sato and
• Alberto Boretti

Beilstein J. Nanotechnol. 2020, 11, 740–769, doi:10.3762/bjnano.11.61

• were studied. Here the correlations between material structural features and the location of SPEs from bulk down to the monolayer was studied at room temperature. Chemical etching and ion irradiation are used to generate the SPEs in h-BN various materials. Their photo-dynamics analysis reveals

• ][119] up to high temperatures and in various environments, with an increased number of defects observed with increased temperature; ion beams of various types, such as Si, O, B, boron−nitrogen (BN) complexes [119], He and N at low fluences [45]; chemical etching [45] based on the use of

• ][120] from low to high energy electrons, with the high energy electrons improving the yield and the spatial distribution of the emitters away from the edges in the center of the flake; oxygen plasma etching associated with annealing [121] and in particular a process of only two steps, including Ar

A novel dry-blending method to reduce the coefficient of thermal expansion of polymer templates for OTFT electrodes

• Xiangdong Ye,
• Bo Tian,
• Yuxuan Guo,
• Fan Fan and
• Anjiang Cai

Beilstein J. Nanotechnol. 2020, 11, 671–677, doi:10.3762/bjnano.11.53

• nanoparticles with a particle size of 500 nm are filled into a structure with an etching size of 50 × 30 × 25 μm. Hence, the weight fraction of the SiO2 nanoparticles is calculated according to Equation 1 [20]: Here, ω is the weight fraction of the SiO2 nanoparticles, ρm is the density of SiO2 (2648 kg·m−3 [18

Silver-decorated gel-shell nanobeads: physicochemical characterization and evaluation of antibacterial properties

• Marta Bartel,
• Katarzyna Markowska,
• Marcin Strawski,
• Krystyna Wolska and
• Maciej Mazur

Beilstein J. Nanotechnol. 2020, 11, 620–630, doi:10.3762/bjnano.11.49

• , optoelectronic elements and biomedical devices [18][19]. Polystyrene beads are also a versatile material that can be quite easily functionalized with sulfonic groups. The particles are incubated with concentrated sulfuric acid at elevated temperature, which results in gradual etching of their surface. Through

Luminescent gold nanoclusters for bioimaging applications

• Nonappa

Beilstein J. Nanotechnol. 2020, 11, 533–546, doi:10.3762/bjnano.11.42

• complexes and SCQD-based nanomaterials. To improve the quantum yield and PL, various approaches have been developed including ligand engineering, selective doping to create alloy clusters, aggregation-induced emission, selective etching and self-assembly [48][49][50][51][52][53][54][55][56][57][58]. Ligands

• the cytoplasm as well as in the nucleus. Muhammed et al. reported brightly NIR-emitting Au23 and Au25 NCs using single-phase and biphasic etching of [Au25(SG)18] (Figure 4B) [87]. The Au23 clusters were selectively conjugated with streptavidin for a specific labeling of cells. Here the strong binding

• –Alexa 594 and nuclear dye SYTO 59; scale bar: 25 μm. B) Schematics showing the etching method to prepare luminescent AuNCs and their conjugation with streptavidin. C) (a) Fluorescence, (b) bright-field, (c) and overlay of fluorescent and bright-field images of human hepatoma (HepG2) cells stained with

Multilayer capsules made of weak polyelectrolytes: a review on the preparation, functionalization and applications in drug delivery

• Varsha Sharma and
• Anandhakumar Sundaramurthy

Beilstein J. Nanotechnol. 2020, 11, 508–532, doi:10.3762/bjnano.11.41

• crosslinking without the need of post treatment [55]. Stable multilayered hollow capsules of N-methyl-2-nitro-diphenylamine-4-diazoresin/m-methylphenol-formaldehyde resin (NDR/MPR) on a PS core based on in situ coupling were found to withstand solvent etching without further processing [55]. The reaction

Nanoarchitectonics: bottom-up creation of functional materials and systems

• Katsuhiko Ariga

Beilstein J. Nanotechnol. 2020, 11, 450–452, doi:10.3762/bjnano.11.36

• that were formed by metal-assisted chemical etching (MACE) [27], and the formation of high-tolerance crystalline hydrogels from cyclic dipeptides upon self-assembly [28]. In addition, a review on the use of DNA as the fundamental material building block for molecular and structural engineering [29

An advanced structural characterization of templated meso-macroporous carbon monoliths by small- and wide-angle scattering techniques

• Felix M. Badaczewski,
• Marc O. Loeh,
• Torben Pfaff,
• Dirk Wallacher,
• Daniel Clemens and
• Bernd M. Smarsly

Beilstein J. Nanotechnol. 2020, 11, 310–322, doi:10.3762/bjnano.11.23

• microporosity additional approaches are necessary to further introduce mesoporosity or macroporosity and to tune the pore system. Chemical and physical activation, using reactive agents such as bases (KOH) or gases (CO2), are only capable to enhance the microporosity by etching the carbon skeleton [33][34]. To

Fabrication of Ag-modified hollow titania spheres via controlled silver diffusion in Ag–TiO₂ core–shell nanostructures

• Bartosz Bartosewicz,
• Malwina Liszewska,
• Bogusław Budner,
• Marta Michalska-Domańska,
• Krzysztof Kopczyński and
• Bartłomiej J. Jankiewicz

Beilstein J. Nanotechnol. 2020, 11, 141–146, doi:10.3762/bjnano.11.12

• template was used in the fabrication of rattle-type HSs of Au@TiO2 using multistep template deposition and a surface-protected etching method [13], of TiO2 HSs of mixed anatase/rutile composition loaded with noble metal NPs (Au, Pt, Pd) [14], and of N-doped Ag/TiO2 HSs [15]. A hard-templating method with a

Influence of the epitaxial composition on N-face GaN KOH etch kinetics determined by ICP-OES

• Markus Tautz,
• Maren T. Kuchenbrod,
• Joachim Hertkorn,
• Robert Weinberger,
• Martin Welzel,
• Arno Pfitzner and
• David Díaz Díaz

Beilstein J. Nanotechnol. 2020, 11, 41–50, doi:10.3762/bjnano.11.4

• , Spain 10.3762/bjnano.11.4 Abstract Roughening by anisotropic etching of N-face gallium nitride is the key aspect in today’s production of blue and white light emitting diodes (LEDs). Both surface area and number of surface angles are increased, facilitating light outcoupling from the LED chip. The

• progress in small time increments with high precision. Thereby, the disadvantages of other techniques such as determination of weight loss or height difference were overcome, achieving high accuracy and reproducibility. Keywords: etching; GaN; ICP-OES; KOH; LED; Introduction The light emitting diode (LED

• , surface roughening is an integral part of flip-chip processing. The two approaches towards surface roughening are wet- and dry-chemical etching [11][12]. During wet etching, aqueous KOH and other alkaline or acidic solutions are commonly used to remove GaN from the N-polar surface in an anisotropic manner