Microneedle-based ocular drug delivery systems – recent advances and challenges

• Piotr Gadziński,
• Anna Froelich,
• Monika Wojtyłko,
• Antoni Białek,
• Julia Krysztofiak and
• Tomasz Osmałek

Beilstein J. Nanotechnol. 2022, 13, 1167–1184, doi:10.3762/bjnano.13.98

• photoresistant layer. The wafer is then etched. A distinction can be made between wet and dry etching. The wet etching process uses a potassium hydroxide solution, while dry etching includes the physical methods ion milling and sputtering and the chemical method high-pressure plasma [156]. Lithographic

Influence of water contamination on the sputtering of silicon with low-energy argon ions investigated by molecular dynamics simulations

• Grégoire R. N. Defoort-Levkov,
• Alan Bahm and
• Patrick Philipp

Beilstein J. Nanotechnol. 2022, 13, 986–1003, doi:10.3762/bjnano.13.86

• formed during the sample preparation by FIB milling [15][16][17]. Such an amorphous layer represents a substantial part of the thickness of the sample and information coming from this part does not correspond to the initial sample structure. Minimizing the thickness of this amorphous layer during FIB

• milling is essential because most samples analysed in high-precision instruments are prepared using this method. This can be best achieved using low-beam energies, ideally in the sub-keV range [18], since low-energy ion beams (under 500 eV) produce a thinner amorphous layer due to their lower penetration

• ignored. Contaminants on the sample surface can also play a critical role during the milling process: water can be found on nearly every sample surface [21]. For example, in a vacuum chamber at a pressure of 10−8 mbar, there are still 106 to 109 molecules per cm3. This contaminant has a strong impact on

Optimizing PMMA solutions to suppress contamination in the transfer of CVD graphene for batch production

• Chun-Da Liao,
• Andrea Capasso,
• Tiago Queirós,
• Telma Domingues,
• Fatima Cerqueira,
• Nicoleta Nicoara,
• Jérôme Borme,
• Paulo Freitas and
• Pedro Alpuim

Beilstein J. Nanotechnol. 2022, 13, 796–806, doi:10.3762/bjnano.13.70

• : C4 PMMA; Wafer 2: B2 PMMA). Both wafers started with the patterning of Cr/Au contacts (deposited by magnetron sputtering) using direct-write laser lithography and ion milling. The fabrication of the two wafers followed slightly different steps, as described below. Wafer 1: A stopping layer (Al2O3

Sputtering onto liquids: a critical review

• Anastasiya Sergievskaya,
• Adrien Chauvin and
• Stephanos Konstantinidis

Beilstein J. Nanotechnol. 2022, 13, 10–53, doi:10.3762/bjnano.13.2

• methods are based on physical transformations of matter. These methods mainly operate with a “top-down” strategy where bulk materials are reduced in size, down to the nanoscale, via their interaction with photons, heat, or ions or via mechanical milling. Those methods are valuable as they are free from

• in the synthesis procedures. The most common physical methods used to generate NPs are high-energy ball milling, laser ablation, electrospraying, inert gas condensation, PVD, laser pyrolysis, flash spray pyrolysis, and melt mixing [16]. Chemical methods are the traditional and most widely used

Measurement of polarization effects in dual-phase ceria-based oxygen permeation membranes using Kelvin probe force microscopy

• Kerstin Neuhaus,
• Christina Schmidt,
• Liudmila Fischer,
• Wilhelm Albert Meulenberg,
• Ke Ran,
• Joachim Mayer and
• Stefan Baumann

Beilstein J. Nanotechnol. 2021, 12, 1380–1391, doi:10.3762/bjnano.12.102

• , KPFM measurements were started with an imaging velocity of 1 image per minute to measure the relaxation of the introduced gradient. Electron microscopy The TEM specimens were cut from 60CSO20-FC2O pellets by focused ion beam (FIB) milling using a FEI Strata400 system with Ga ion beam. Further thinning

Progress and innovation of nanostructured sulfur cathodes and metal-free anodes for room-temperature Na–S batteries

• Marina Tabuyo-Martínez,
• Bernd Wicklein and
• Pilar Aranda

Beilstein J. Nanotechnol. 2021, 12, 995–1020, doi:10.3762/bjnano.12.75

• ]. However, important issues are the need for elevated temperatures, working under sealed Ar or N2 conditions, and the possibly inhomogeneous sulfur distribution within the host material. Therefore, also ball milling is being employed to produce fine sulfur particles (tens of nanometers) from sulfur powder

Is the Ne operation of the helium ion microscope suitable for electron backscatter diffraction sample preparation?

• Annalena Wolff

Beilstein J. Nanotechnol. 2021, 12, 965–983, doi:10.3762/bjnano.12.73

• alterations and, in some instances, phase transformation of Cu to Cu3Ga occurred when polishing with Ga ions. Polishing with high-energy Ne ions at a glancing angle maintains the crystal structure and significantly improves indexing in EBSD measurements. By milling down to a depth equaling the depth of the

• was measured by TEM for different grains (see Supporting Information File 1). Both the TEM image and the FSD image, the latter is recorded with the EBSD detector and highlights the surface topography, show the different milling depths for different grains. Faster milling grains were milled to a 226 nm

• mass of 63.55 g/mol. For the slower milling grain, which only milled to a depth of 110 nm during the irradiation, the steady-state condition is reached significantly later within ≈40 s, allowing for up to 7.6 × 1010 Ga ions to be implanted in these grains. This corresponds to a 36% of impurity

Uniform arrays of gold nanoelectrodes with tuneable recess depth

• Elena O. Gordeeva,
• Ilya V. Roslyakov,
• Alexey P. Leontiev,
• Alexey A. Klimenko and
• Kirill S. Napolskii

Beilstein J. Nanotechnol. 2021, 12, 957–964, doi:10.3762/bjnano.12.72

• direct-writing using electron beam lithography [11][12] or ion beam milling [13][14]) are limited by the ensemble area and expensive in mass production, but allow one to precisely tune the parameters of an array (a geometry of individual electrodes and the distance between them) over a wide range. An

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

• Frances I. Allen

Beilstein J. Nanotechnol. 2021, 12, 633–664, doi:10.3762/bjnano.12.52

• ; focused helium ion beam-induced deposition; focused helium ion beam milling; helium ion beam lithography; helium ion implantation; Introduction Since the helium ion microscope (HIM) was introduced 15 years ago [1][2][3], over one hundred HIMs have been installed worldwide and over one thousand research

• following, the field of materials modification research using the HIM is reviewed, subdivided into the following areas: 1. defect engineering, 2. ion implantation, 3. irradiation-induced restructuring, 4. resist-based lithography, 5. direct-write lithography/milling (including gas-assisted milling), and 6

• effects. In the case of neon (also shown in Figure 1b), there is more scattering close to the surface, but the advantage for milling is a sputter yield that is about two orders of magnitude higher than that of helium at the same beam energy [17]. Early HIM work by Livengood et al. investigated the

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

• ranging from several days to one or two months. For imaging and nanofabrication, only one of the three atoms is selected. This nearly ideal point source allows not only for high-resolution imaging but also for the milling of smallest geometric features [5][6][7]. Furthermore, large-area machining is

• was sputtered with two empty square windows of 100 × 100 μm2 in size, where the flakes were placed. The fabrication of the tetramer structures was carried out using Ga ion beam milling only, or a combination of He ion beam milling for the definition of the tetramer and Ga ion beam milling for the

• . For Ga ion beam milling a current of 10 pA, a pitch of 3 nm and a dwell time of 1 μs were employed in a two-step patterning process. First, the surrounding gold was removed by rectangular scanning of a square of several micrometers from which a slightly larger tetramer shape was subtracted

Scanning transmission helium ion microscopy on carbon nanomembranes

• Daniel Emmrich,
• Annalena Wolff,
• Nikolaus Meyerbröker,
• Jörg K. N. Lindner,
• André Beyer and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2021, 12, 222–231, doi:10.3762/bjnano.12.18

• established as a key nanofabrication tool for milling [7][8][9], defect engineering [10][11], and resist-based lithography [12][13], overcoming the resolution limitations of other FIB techniques [14][15]. Both bulk samples as well as thin membranes have been structured using the HIM. On membranes, the sputter

• yield is significantly increased because sputtering occurs not only in backward but also in forward direction [16][17]. To observe and control the milling process, the ion transmission signal is preferred over the SE signal because it is related to the membrane thickness. The detection of the

• -field signal, similar to scanning transmission electron microscopy (STEM). In this way, it is possible to check qualitatively the milling progress on membranes or even to determine quantitatively the thickness of a sample. Notte et al. used thickness fringes on MgO crystals for thickness determination

A review on the green and sustainable synthesis of silver nanoparticles and one-dimensional silver nanostructures

• Sina Kaabipour and
• Shohreh Hemmati

Beilstein J. Nanotechnol. 2021, 12, 102–136, doi:10.3762/bjnano.12.9

• ” synthesis methods. Several physical methods for top-down synthesis of silver nanostructures including ball milling [105][106][107], laser ablation [108][109][110][111][112], evaporation–condensation [113][114], electromagnetic levitation gas condensation (ELGC) [115], ultrasonication [116][117][118][119

• not necessarily require using a reducing agent or stabilizer; however, they may be incorporated with other techniques. 2.1.1 Ball milling process. As one of the conventional processes, the ball milling process (mostly used as mechanochemical ball milling) is a method that is used commonly to produce

• AgNPs in a solid state [220]. Previously, AgNPs were produced using high-energy planetary ball milling [105][106][221]. Khayati et al. [105] utilized planetary ball milling in a mechanochemical process by adding organic process control agents (PCAs). In this work, depending on the type of PCA used

Bio-imaging with the helium-ion microscope: A review

• Matthias Schmidt,
• James M. Byrne and
• Ilari J. Maasilta

Beilstein J. Nanotechnol. 2021, 12, 1–23, doi:10.3762/bjnano.12.1

• , HIM is not just an imaging technique. The ability to use the instrument for milling biological objects as small as viruses offers unique opportunities which are not possible with more conventional focused ion beams, such as gallium. Several pioneering technical developments, such as methods to couple

• imaging of insulating samples with nanoscale milling capabilities in one instrument. The milling efficiency can also be increased by the use of heavier ion species, such as Ne or Ga, where Ne is available for the standard He column, whereas Ga requires an additional column. In contrast to its success in

• that HIM is compatible with the powerful technique of immunogold labelling. Secondly, Joens et al. introduced the ion-beam milling capabilities of the HIM to biological applications when they opened up the mouth cavity of a nematode [6]. In the same paper, Joens et al. furthermore demonstrated on

Imaging and milling resolution of light ion beams from helium ion microscopy and FIBs driven by liquid metal alloy ion sources

• Nico Klingner,
• Gregor Hlawacek,
• Paul Mazarov,
• Wolfgang Pilz,
• Fabian Meyer and
• Lothar Bischoff

Beilstein J. Nanotechnol. 2020, 11, 1742–1749, doi:10.3762/bjnano.11.156

• compared with ion beams such as lithium, beryllium, boron, and silicon, obtained from a mass-separated FIB using a liquid metal alloy ion source (LMAIS) with respect to the imaging and milling resolution, as well as the current stability. Simulations were carried out to investigate whether the

• experimentally smallest ion-milled trenches are limited by the size of the collision cascade. While He+ offers, experimentally and in simulations, the smallest minimum trench width, light ion species such as Li+ or Be+ from a LMAIS offer higher milling rates and ion currents while outperforming the milling

• ][29] was used. All milling experiments were performed on a 100 nm thin gold film on glass. For measuring the trench width milled into the gold layer, either the same primary ion beam microscope or a scanning electron microscope have been used to image the sputtered trenches. The investigated sources

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

• direct, maskless surface patterning with a superior lateral resolution and depth control [2][3]. The portfolio of the currently used FIB-based and FIB-assisted surface patterning techniques includes a number of different methods, such as ion-beam sputtering of surface layers (ion-beam milling), ion-beam

• comprehend its limitations and advantages, especially in comparison to the direct 3D patterning with FIB milling. First of all, we noticed that the method is limited to the fabrication of low-aspect-ratio pattern features and does not impose a challenge to the area of high-aspect-ratio and high-lateral

• -precision 3D structures, in which FIB milling is a well-established technique for a broad range of materials. This limitation results from a combination of the limited capacity of the polymer substrates to shrink and a relatively large lateral straggle of He+ ions scattered in the bulk of the polymer

Controlling the proximity effect in a Co/Nb multilayer: the properties of electronic transport

• Sergey Bakurskiy,
• Mikhail Kupriyanov,
• Nikolay V. Klenov,
• Igor Soloviev,
• Andrey Schegolev,
• Roman Morari,
• Yury Khaydukov and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1336–1345, doi:10.3762/bjnano.11.118

• transport measurements was etched under pure argon atmosphere (Ar+ milling) in a CRYO RIE Alba Nova machine (Stockholm University). The patterned design allowed for a four-point type measurement of six segments of the sample in one cooling cycle (Figure 4). The pair of contacts was applied for setting the

3D superconducting hollow nanowires with tailored diameters grown by focused He⁺ beam direct writing

• Rosa Córdoba,
• Alfonso Ibarra,
• Dominique Mailly,
• Isabel Guillamón,
• Hermann Suderow and
• José María De Teresa

Beilstein J. Nanotechnol. 2020, 11, 1198–1206, doi:10.3762/bjnano.11.104

• diameter on the ion beam current (Figure 3b), which indicates that the ion beam forms the cavity due to a milling effect. Thus via tuning the ion beam current and dose we have full control to tailor the diameters of the hollow 3D NWs. The specific deposition parameters and NW diameters are listed in Table

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

• (yielding to the same porosity), changing only the second anodization time (from 120 to 600 s) to obtain different film thicknesses (from 209 ± 12 nm to 380 ± 15 nm). Focused ion beam (FIB) milling and field-emission scanning electron microscopy (FESEM) imaging were used to accurately determine the

Facile biogenic fabrication of hydroxyapatite nanorods using cuttlefish bone and their bactericidal and biocompatibility study

• Satheeshkumar Balu,
• Manisha Vidyavathy Sundaradoss,
• Swetha Andra and
• Jaison Jeevanandam

Beilstein J. Nanotechnol. 2020, 11, 285–295, doi:10.3762/bjnano.11.21

• washed with distilled water, followed by acetone and ethanol to remove surface contaminants. The washed bones were dried in a hot air oven (Indfurr model OR-3795) at 60 °C for 24 h and 20 g of cuttlefish bone pieces were taken for top down processing using high-energy ball milling (VB Ceramic Consultants

pH-Controlled fluorescence switching in water-dispersed polymer brushes grafted to modified boron nitride nanotubes for cellular imaging

• Saban Kalay,
• Yurij Stetsyshyn,
• Volodymyr Donchak,
• Khrystyna Harhay,
• Ostap Lishchynskyi,
• Halyna Ohar,
• Yuriy Panchenko,
• Stanislav Voronov and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2019, 10, 2428–2439, doi:10.3762/bjnano.10.233

• irradiation [43], by mechanical milling [44] or with the iminoborane treatment [45]. The first step in covalent bonding of oligoperoxide to BNNT surfaces is to bind pyromellitic chloroanhydride moieties through available amino groups. The second step involves the grafting polymerization “from the surface” of

Preservation of rutin nanosuspensions without the use of preservatives

• Pascal L. Stahr and
• Cornelia M. Keck

Beilstein J. Nanotechnol. 2019, 10, 1902–1913, doi:10.3762/bjnano.10.185

• are precipitation, wet milling, high-pressure homogenization or combinations of these methods [1][2][3][4]. Regardless of the process used, all these methods will yield nanosuspensions, i.e., nanocrystals dispersed in a liquid. As liquid formulations are not always a convenient dosage form for the

TiO₂/GO-coated functional separator to suppress polysulfide migration in lithium–sulfur batteries

• Ning Liu,
• Lu Wang,
• Taizhe Tan,
• Yan Zhao and
• Yongguang Zhang

Beilstein J. Nanotechnol. 2019, 10, 1726–1736, doi:10.3762/bjnano.10.168

• TiO2/GO composites (90 wt %) and poly(vinylidene fluoride) (PVDF, 10 wt %) in ultrapure water and milling for 40 min. The as-prepared slurry was coated onto the separator and dried at 60 °C in a vacuum oven for 8 h. Then, the TiO2/GO-coated separator was sectioned in the form of circular discs with a

Nanoporous smartPearls for dermal application – Identification of optimal silica types and a scalable production process as prerequisites for marketed products

• David Hespeler,
• Sanaa El Nomeiri,
• Jonas Kaltenbach and
• Rainer H. Müller

Beilstein J. Nanotechnol. 2019, 10, 1666–1678, doi:10.3762/bjnano.10.162

• scale by bead milling or high-pressure homogenization. Skin penetration studies showed that the smartPearls were actually superior to the nanocrystals [8][24][25]. However, the market introduction in final cosmetic products was blocked due to the lack of an industrial supplier of active agent-loaded

• smartPearls. To establish an industrial supply, an industrially feasible production method is required, which is the focus of this work. Silica particles can be loaded by co-milling [26][27], however, with this technique, a large portion of the active agents are not incorporated into the pores. Loading can be

Subsurface imaging of flexible circuits via contact resonance atomic force microscopy

• Wenting Wang,
• Chengfu Ma,
• Yuhang Chen,
• Lei Zheng,
• Huarong Liu and
• Jiaru Chu

Beilstein J. Nanotechnol. 2019, 10, 1636–1647, doi:10.3762/bjnano.10.159

• 11 wt % PMMA in anisole solvent at 1500 rpm for 5 min, resulting in a thickness of approximately 3.5 µm. Then, a 300 nm thick Au film was sputtered on the PMMA substrate by using magnetron sputtering. The Au film was subsequently patterned by focused ion beam (FIB) milling (FEI, Helios NanoLab 650

Upcycling of polyurethane waste by mechanochemistry: synthesis of N-doped porous carbon materials for supercapacitor applications

• Christina Schneidermann,
• Pascal Otto,
• Desirée Leistenschneider,
• Sven Grätz,
• Claudia Eßbach and
• Lars Borchardt

Beilstein J. Nanotechnol. 2019, 10, 1618–1627, doi:10.3762/bjnano.10.157

• inorganic chemistry [59][60][61][62]. Mechanochemical reactions are initiated and controlled by mechanical energy, for example provided by the collisions of milling balls in high-energy ball mills. The advantages of mechanochemistry are obvious. Syntheses can be conducted without solvents [63][64], and

• within short reaction times [59][65]. Also, the potential of mechanochemistry for upscaling has recently been discussed by Stolle and co-workers. An upscaling from the milligram scale to the multiple-gram scale has been shown to be feasible [66][67]. For the kilogram scale other milling techniques such

• optionally be added to further increase the nitrogen content. Pre-milling of the PU foam and the mechanochemical reaction of all components are carried out in a planetary ball mill. The received polymer mixture is carbonized to form a nitrogen-doped carbon material with a surface area of up to 2150 m2·g−1