Exploring the fabrication and transfer mechanism of metallic nanostructures on carbon nanomembranes via focused electron beam induced processing

• Christian Preischl,
• Linh Hoang Le,
• Elif Bilgilisoy,
• Armin Gölzhäuser and
• Hubertus Marbach

Beilstein J. Nanotechnol. 2021, 12, 319–329, doi:10.3762/bjnano.12.26

• without any changes, aside from oxidation. Here we demonstrate that iron as well as cobalt oxide structures on top of a cross-linked SAM on Ag/mica do change more significantly. The Fe(NO3)3 solution used for etching of the Ag layer also dissolves the cobalt oxide structures and causes dissolution and

• reduction of the iron structures. These results demonstrate that the fabrication of hybrids of metallic nanostructures onto organic 2D materials is an intrinsically complex procedure. The interactions among the metallic deposits, the substrate for the growth of the SAM, and the associated etching/dissolving

• nanostructures by investigating the fabrication and transfer on the example of a SAM of TPT on a silver substrate. Consequently, a different chemical etching process is needed for the lift-off process during the transfer. In the case of gold, an etching solution of KI/I2/H2O is used. Whereas in this approach

The patterning toolbox FIB-o-mat: Exploiting the full potential of focused helium ions for nanofabrication

• Victor Deinhart,
• Lisa-Marie Kern,
• Jan N. Kirchhof,
• Sabrina Juergensen,
• Joris Sturm,
• Enno Krauss,
• Thorsten Feichtner,
• Sviatoslav Kovalchuk,
• Michael Schneider,
• Dieter Engel,
• Bastian Pfau,
• Bert Hecht,
• Kirill I. Bolotin,
• Stephanie Reich and
• Katja Höflich

Beilstein J. Nanotechnol. 2021, 12, 304–318, doi:10.3762/bjnano.12.25

• sheet was covered by a 500 nm thick PMMA layer. After etching the copper foil, the graphene sheet was transferred onto a SiN membrane with a regular grid of holes. The transfer process is described in detail elsewhere [52]. The SiN membrane was covered with a thin layer of gold, which allowed us to

Numerical analysis of vibration modes of a qPlus sensor with a long tip

• Kebei Chen,
• Zhenghui Liu,
• Yuchen Xie,
• Chunyu Zhang,
• Gengzhao Xu,
• Wentao Song and
• Ke Xu

Beilstein J. Nanotechnol. 2021, 12, 82–92, doi:10.3762/bjnano.12.7

• purity of 99.95%. The tip was obtained by AC electrochemical etching in NaOH solution at a concentration of 1 mol·L−1. A tungsten wire with a length of 942 μm was attached to the end of the tuning fork with Torr seal epoxy. The angle between the tungsten wire and the prong was 65°. The excitation signal

ZnO and MXenes as electrode materials for supercapacitor devices

• Ameen Uddin Ammar,
• Ipek Deniz Yildirim,
• Feray Bakan and
• Emre Erdem

Beilstein J. Nanotechnol. 2021, 12, 49–57, doi:10.3762/bjnano.12.4

• batteries [15][20][21][23]. Gogotsi et al. [24][25][26], who are the pioneers of MXene materials, have defined the relation to MAX phases in a very clear way: MXenes can be produced by etching the A layer from MAX phases. The suffix “ene” is added to emphasize the similarity to graphene. MAX phases are a

• carbon and/or nitrogen [15][18][19][21][23] with n = 1–3. In addition, MAX phases and MXenes are conducting ceramics [15][18][27]. Several etching processes have been developed to synthesize particular MXenes. With the results not meeting with expectations, the scientists understood that MAX phases are

• structure. After the etching process, MXenes have a great number of active groups, such as –OH and =O, which results in superior hydrophilicity, chemical reactivity, and large contact area. This implies a potential of MXenes for the use in supercapacitors [16][18][19][22][23][28]. Moreover, MXenes can be

Towards 3D self-assembled rolled multiwall carbon nanotube structures by spontaneous peel off

• Jonathan Quinson

Beilstein J. Nanotechnol. 2020, 11, 1865–1872, doi:10.3762/bjnano.11.168

• ]. However, support-free 3D structures typically require extra synthesis steps. “Sponges” or “cages” can be produced by freeze-drying preformed CNTs [10] or by etching template materials [11]. A way to tune CNT properties further is to introduce other elements in the carbon network (e.g., nitrogen [12][13

Piezotronic effect in AlGaN/AlN/GaN heterojunction nanowires used as a flexible strain sensor

• Jianqi Dong,
• Liang Chen,
• Yuqing Yang and
• Xingfu Wang

Beilstein J. Nanotechnol. 2020, 11, 1847–1853, doi:10.3762/bjnano.11.166

• , AlGaN/AlN/GaN NWs with high electron mobility, carrier density, and mechanical flexibility have become good candidates for highly sensitive and flexible strain sensors. In this work, we use a top-down two-step process, including inductively coupled plasma (ICP) dry etching and selective electrochemical

• (EC) wet etching, to prepare AlGaN/AlN/GaN heterojunction NWs with a controllable size. After the lift-off, a single NW is transferred to a flexible poly(ethylene terephthalate) (PET) substrate and is fixed by indium tin oxide (ITO) electrodes to form an ohmic contact for the strain sensor. Under

• spreading of the current. Next, 500 nm of an unintentionally doped GaN layer was deposited to protect the lower layer during the selective EC etching. A heavily doped GaN (N+-GaN) sacrificial layer, sandwiched by two thin N++-GaN layers was inserted under the AlGaN/AlN/GaN layer to enhance the conductivity

Unravelling the interfacial interaction in mesoporous SiO₂@nickel phyllosilicate/TiO₂ core–shell nanostructures for photocatalytic activity

• Bridget K. Mutuma,
• Xiluva Mathebula,
• Isaac Nongwe,
• Bonakele P. Mtolo,
• Boitumelo J. Matsoso,
• Rudolph Erasmus,
• Zikhona Tetana and
• Neil J. Coville

Beilstein J. Nanotechnol. 2020, 11, 1834–1846, doi:10.3762/bjnano.11.165

• formation of the NiPS, the average pore size increased to 6.3 nm in the mSiO2@NiPS spheres (Table 1). This can be attributed to the formation of the sheet-like NiPS on the SiO2 surface and/or a possible partial etching of silica during the deposition-precipitation process by the alkaline solution (urea

Electron beam-induced deposition of platinum from Pt(CO)₂Cl₂ and Pt(CO)₂Br₂

• Aya Mahgoub,
• Hang Lu,
• Rachel M. Thorman,
• Konstantin Preradovic,
• Titel Jurca,
• Lisa McElwee-White,
• Howard Fairbrother and
• Cornelis W. Hagen

Beilstein J. Nanotechnol. 2020, 11, 1789–1800, doi:10.3762/bjnano.11.161

• has very high design flexibility and does not require masks or resist and development. Moreover, it does not need to be performed in a clean room with multiple process stages, such as spin coating, deposition, development, and etching; it is a single step process [1]. The process starts by injecting a

• exceeding the maximum pressure allowed in the SEM chamber (approximately 10−4 mbar). A silicon substrate was used for all deposition experiments, patterned such that circular areas of pristine silicon are surrounded by black silicon (obtained by reactive ion etching). The black silicon area aids in focusing

Mapping of integrated PIN diodes with a 3D architecture by scanning microwave impedance microscopy and dynamic spectroscopy

• Rosine Coq Germanicus,
• Peter De Wolf,
• Florent Lallemand,
• Catherine Bunel,
• Serge Bardy,
• Hugues Murray and
• Ulrike Lüders

Beilstein J. Nanotechnol. 2020, 11, 1764–1775, doi:10.3762/bjnano.11.159

• second area of interest was the bottom of a deep trench (area 2 in Figure 2). Deep trenches were fabricated by dry etching pores with a high aspect ratio and a diameter of 1 µm. During the FEOL processing, trenches were filled with a dielectric layer, followed by an in situ highly phosphorus-doped

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