3D Nanoprinting via laser-assisted electron beam induced deposition: growth kinetics, enhanced purity, and electrical resistivity

• Brett B. Lewis,
• Robert Winkler,
• Xiahan Sang,
• Pushpa R. Pudasaini,
• Michael G. Stanford,
• Harald Plank,
• Raymond R. Unocic,
• Jason D. Fowlkes and
• Philip D. Rack

Beilstein J. Nanotechnol. 2017, 8, 801–812, doi:10.3762/bjnano.8.83

• electron beam dwell time while at the same time maintaining minimal thermal drift. Finally, in this work, we investigate the effect of reactive gas on the laser-assisted in situ purification of 3D features synthesized using EBID from the commonly employed precursor MeCpPt(IV)Me3. Notably, we explore the

• for the standard conditions and varied as discussed to control the precursor flux. 3D structures were patterned by controlling the spatial coordinates of the electron beam as well as the dwell time at each point via a text file read by the microscope software. For all patterns, a pixel point pitch of

• Growth rates The relation between the vertical and lateral growth rates is a critical parameter required to accurately and reproducibly construct 3D nanostructures. Once this relation is known, the beam dwell time and pitch can be adjusted as necessary to construct more complex shapes [60]. A simple unit

Phospholipid arrays on porous polymer coatings generated by micro-contact spotting

• Sylwia Sekula-Neuner,
• Monica de Freitas,
• Lea-Marie Tröster,
• Tobias Jochum,
• Pavel A. Levkin,
• Michael Hirtz and
• Harald Fuchs

Beilstein J. Nanotechnol. 2017, 8, 715–722, doi:10.3762/bjnano.8.75

• substrate (dwell time), different feature sizes can be obtained (Figure 1). The diameter of the spotted features varies from 6 +/− 0.3 µm to 4 +/− 0.2 µm for dwell times from 3 to 0.1 s. Interestingly, not only feature size, but also fluorescence intensity varies with dwell time (Figure 1b). This can be

• explained by the 3D nature of the features as they are actually embedded in the porous HEMA-EDMA substrate [10]. While on a flat glass substrate, features can only grow into 2D with dwell time, while in the present case features will also grow into the depth of the HEMA-EDMA film, resulting in brighter

• intensity against dwell time (Figure 3b) indicates a slight dependence of fluorescence intensity on dwell time (suggesting the infiltrated nature of the features as explained above). Though the difference between 2 s, 1 s and 0.5 s dwell time is not as strongly pronounced as in the case of the DOPC ink

Ion beam profiling from the interaction with a freestanding 2D layer

• Ivan Shorubalko,
• Kyoungjun Choi,
• Michael Stiefel and
• Hyung Gyu Park

Beilstein J. Nanotechnol. 2017, 8, 682–687, doi:10.3762/bjnano.8.73

• method to extract pore-diameter values for each parameter set of the ion beam exposure. Figure 1d shows the dependency of the pore diameters on the Ga+ ion dose extracted from beam current and dwell time. Data for two instrument apertures corresponding to two different beam currents are presented

• doses and then gradually increase for larger doses. For 1.5 pA Ga-FIB current and 0.5 ms dwell time pores with diameters as small as 5 nm could be reliably created and identified. Dwell times of 0.3 ms resulted in a large statistical variation of pore diameters: from a few nanometers down to no pores

• , the rather flat top part of the beam profile will create enough collision events with graphene to open the initial pore. This process is unstable and very sensitive to the dwell time. Thus, initial pore formation can be seen as a stochastic process. Once the initial pore is created the graphene

Thickness-modulated tungsten–carbon superconducting nanostructures grown by focused ion beam induced deposition for vortex pinning up to high magnetic fields

• Ismael García Serrano,
• Javier Sesé,
• Isabel Guillamón,
• Hermann Suderow,
• Sebastián Vieira,
• Manuel Ricardo Ibarra and
• José María De Teresa

Beilstein J. Nanotechnol. 2016, 7, 1698–1708, doi:10.3762/bjnano.7.162

• grown. The growth parameters used in the FIBID fabrication process were: Vbeam = 30 kV, Ibeam = 80 pA, beam spot diameter = 39 nm, beam dwell time = 200 ns, x-pitch = 100 nm, number of passes = 177988, raster scan mode, precursor temperature = 55 °C, chamber base pressure ≈1 × 10−6 mbar, chamber growth

Efficient electron-induced removal of oxalate ions and formation of copper nanoparticles from copper(II) oxalate precursor layers

• Kai Rückriem,
• Sarah Grotheer,
• Henning Vieker,
• Paul Penner,
• André Beyer,
• Armin Gölzhäuser and
• Petra Swiderek

Beilstein J. Nanotechnol. 2016, 7, 852–861, doi:10.3762/bjnano.7.77

• . A dwell time per pixel between 30 and 100 μs without averaging as well as 1 μs with averaging 64 lines was used. The HIM micrographs were recorded with pixel sizes between 0.49 and 0.98 nm. Results Reflection absorption infrared spectroscopy As described previously, the deposition of copper(II

Single pyrimidine discrimination during voltage-driven translocation of osmylated oligodeoxynucleotides via the α-hemolysin nanopore

• Yun Ding and
• Anastassia Kanavarioti

Beilstein J. Nanotechnol. 2016, 7, 91–101, doi:10.3762/bjnano.7.11

• a less favored configuration as well as to a different solvation shell that “carries along” only what is critically important; all these changes are then detected as current modulation and slower dwell time. In an attempt to understand the source of the differences between dT(OsBp) and dC(OsBp) we

• . The observation that the nanopore discriminates by both residual current and dwell time, among a single dT(OsBp), a single dC(OsBp), and a purine, provide proof-of-principle for nanopore-based sequencing using osmylated DNA as a surrogate. Further optimization of the conditions is necessary to

Fabrication of hybrid nanocomposite scaffolds by incorporating ligand-free hydroxyapatite nanoparticles into biodegradable polymer scaffolds and release studies

• Balazs Farkas,
• Marina Rodio,
• Ilaria Romano,
• Alberto Diaspro,
• Romuald Intartaglia and
• Szabolcs Beke

Beilstein J. Nanotechnol. 2015, 6, 2217–2223, doi:10.3762/bjnano.6.227

• Berkovich tip with a maximum load of 0.6 mN, a dwell time at maximum load of 30 s, loading and unloading periods of 30 and 15 s, respectively. Every sample has been measured at 16 different points (in a matrix of 4 × 4, the distance between measurement points was 50 μm). Young’s modulus was calculated

The role of low-energy electrons in focused electron beam induced deposition: four case studies of representative precursors

• Rachel M. Thorman,
• Ragesh Kumar T. P.,
• D. Howard Fairbrother and
• Oddur Ingólfsson

Beilstein J. Nanotechnol. 2015, 6, 1904–1926, doi:10.3762/bjnano.6.194

• the electron beam and the vertical dimensions are controlled through variation of the dwell time. Precursor molecules used for depositing metal-containing nanostructures are typically organometallic compounds with a central metal atom and ligand architectures that lend the compounds the following

Imaging of carbon nanomembranes with helium ion microscopy

• André Beyer,
• Henning Vieker,
• Robin Klett,
• Hanno Meyer zu Theenhausen,
• Polina Angelova and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2015, 6, 1712–1720, doi:10.3762/bjnano.6.175

• rather than from the freestanding CNMs itself, as schematically depicted in Figure 1e. The intact CNMs completely block the path of such secondary electrons to the detector while partially ruptured CNMs do not. The reduction of the beam current, the dwell time per pixel, the use of frame averaging as

• hitting the holey carbon film, as illustrated in Figure 4e. Figure 5 gives an image series that demonstrates the effect of charging. All images were recorded with a very low dwell time, maximum frame averaging, but without charge compensation and with different beam currents. The contrast and brightness

• images, the working distance was chosen to be as high as 37 mm, which allowed the acquisition of images with a very large field of view. The following imaging parameters were employed for optimized CNM imaging: a dwell time of 0.5 µs, up to 255 frame averages, and with the electron flood gun operated in

Continuum models of focused electron beam induced processing

• Milos Toth,
• Charlene Lobo,
• Vinzenz Friedli,
• Aleksandra Szkudlarek and
• Ivo Utke

Beilstein J. Nanotechnol. 2015, 6, 1518–1540, doi:10.3762/bjnano.6.157

• dissociative chemisorption pathway, leading to fluorination of many surfaces [69][70][71][75]. The model in [17] is a variant of the above model of thermally activated chemisorption defined by Equation 40–Equation 52. Electron beam dwell time as a control parameter of the composition of materials deposited

• electron-beam exposure (dwell time) is given by: with the constants ndA,B, kd, ΔnA,B, κ defined in [8]. The dissociation yields YA,B are then obtained by integrating over the electron beam dwell time: A graphical representation of Equation 66 and Equation 67 is shown in Figure 17. As the molecule fluxes

• , residence times, and dissociation cross-sections of molecules “A” and “B” are very likely different from each other, it can be seen that the composition (given by the magnitude Z on the right hand axis) of the deposits can be tuned by changing the electron beam dwell time per pixel. Equation 64 and Equation

Formation of pure Cu nanocrystals upon post-growth annealing of Cu–C material obtained from focused electron beam induced deposition: comparison of different methods

• Aleksandra Szkudlarek,
• Alfredo Rodrigues Vaz,
• Yucheng Zhang,
• Andrzej Rudkowski,
• Czesław Kapusta,
• Rolf Erni,
• Stanislav Moshkalev and
• Ivo Utke

Beilstein J. Nanotechnol. 2015, 6, 1508–1517, doi:10.3762/bjnano.6.156

• about 10 monolayers per second for Cu(hfac)2. The exposure parameters for Cu(hfac)2 for 1 µm × 1 µm square deposits were: dwell time of 1 µs, pixel distance of 0.4 nm, and frame repetitions varying from 100 to 1000 with refreshment times of 0.625 s. The beam current was 0.4 nA. This corresponds to doses

• of 0.25 nC/µm2 (100 repetitions) and 2.5 nC/µm2 (1000 repetitions). For the 15 μm long lines we used 100 µs dwell time per pixel, 0.5 nm pixel distance, and 300 line repetitions with a refreshment time of 3 s. The beam current was 1 nA, which corresponds to the dose of 9 nC/µm2 and exposure time of

• ]). Upon annealing the same precipitation at deposit surfaces and at halo regions due to forward and backscattered electrons can be seen (Figure 5a–c). For a tip deposit the same features develop upon heating pointing to the fact that the dwell time per pixel during FEBID is not a very sensitive parameter

Structural transitions in electron beam deposited Co–carbonyl suspended nanowires at high electrical current densities

• Gian Carlo Gazzadi and
• Stefano Frabboni

Beilstein J. Nanotechnol. 2015, 6, 1298–1305, doi:10.3762/bjnano.6.134

• –metallorganic SNWs [23]. While FEBID deposits are usually grown on a substrate, suspended deposition is obtained by moving the electron beam away from an elevated edge under gas flow. If the scanning speed (beam stepsize/beam dwell time) is properly tuned, a self-standing nanowire can be deposited along the

Surface excitations in the modelling of electron transport for electron-beam-induced deposition experiments

• Francesc Salvat-Pujol,
• Roser Valentí and
• Wolfgang S. Werner

Beilstein J. Nanotechnol. 2015, 6, 1260–1267, doi:10.3762/bjnano.6.129

• than half of it [44]. The probability for an electron that crosses a surface to undergo a surface excitation is, to a first approximation [45], proportional to the surface dwell time , where is the projectile energy and θ is the surface crossing angle with respect to the surface normal. The energy

High sensitivity and high resolution element 3D analysis by a combined SIMS–SPM instrument

• Yves Fleming and
• Tom Wirtz

Beilstein J. Nanotechnol. 2015, 6, 1091–1099, doi:10.3762/bjnano.6.110

• instrument based on a Cameca NanoSIMS 50 is presented in detail elsewhere [6][7]. The sample was sputtered with a Cs+ primary ion beam at 16 keV impact energy, normal incidence and sample currents between 1.4 and 2.5 pA. The raster frame was set to 256 × 256 pixels. Depending on the analysis, the dwell time

Tunable magnetism on the lateral mesoscale by post-processing of Co/Pt heterostructures

• Oleksandr V. Dobrovolskiy,
• Maksym Kompaniiets,
• Roland Sachser,
• Fabrizio Porrati,
• Christian Gspan,
• Harald Plank and
• Michael Huth

Beilstein J. Nanotechnol. 2015, 6, 1082–1090, doi:10.3762/bjnano.6.109

• precursor gas was (CH3)3Pt(CpCH3), the beam parameters were 5 kV/1 nA, the pitch was 20 nm, the dwell time was 1 μs, the precursor temperature was 44 °C, and the process pressure was 9.5 × 10−6 mbar for a needle position of the gas injector at 100 μm height and 100 μm lateral shift from the writing field

• preparation of the top layers of the structures. In the FEBID process the precursor gas was Co2(CO)8, the beam parameters were 5 kV/1 nA, the pitch was 20 nm, the dwell time was 50 μs, the precursor temperature was 27 °C, and the process pressure was 8.85 × 10−6 mbar. Before the deposition, the chamber was

• chamber up to a pressure of 1.5 × 10−5 mbar. While kept at 300 °C, samples A and C, and D were additionally irradiated with the electron beam (5 kV/1 nA, 20 nm pitch, 50 μs dwell time), whereas sample B was left non-irradiated. The irradiation dose was 100 nC/μm2 for all irradiated samples. After this

Electron-stimulated purification of platinum nanostructures grown via focused electron beam induced deposition

• Brett B. Lewis,
• Michael G. Stanford,
• Jason D. Fowlkes,
• Kevin Lester,
• Harald Plank and
• Philip D. Rack

Beilstein J. Nanotechnol. 2015, 6, 907–918, doi:10.3762/bjnano.6.94

• purification reaction probability is highest since the O2 interfacial concentration is the highest. As the dwell time persists, O2 is consumed and the reaction probability dynamically decreases. The lower current study indicates that the integrated efficiency during the entire pixel dwell time is approximately

• performed using the FEI GIS and MeCpPt(IV)Me3 precursor which raised the chamber pressure to ≈1.5 × 10−5 mbar. 500 × 500 nm boxes were synthesized at this elevated pressure using the NOVA patterning software with a beam energy of 5 keV, beam current of 120 pA, point pitch of 13.55 nm, a pixel dwell time of

• flow of O2. Typical purification parameters were: a beam energy and current of 5 keV and 1.8 nA, respectively, a ≈0.65 nm point pitch with a field of view of 1024 × 884 pixels (665 × 575 nm), a dwell time of 100 ns, and a typical curing time of 20 min. To characterize the reduction in PtCx deposit size

Low-cost formation of bulk and localized polymer-derived carbon nanodomains from polydimethylsiloxane

• Juan Carlos Castro Alcántara,
• Mariana Cerda Zorrilla,
• Lucia Cabriales,
• Luis Manuel León Rossano and
• Mathieu Hautefeuille

Beilstein J. Nanotechnol. 2015, 6, 744–748, doi:10.3762/bjnano.6.76

• technique that allows laser micropattern formation in PDMS [15]. The setup used to locally etch polymer layers at the surface is based on a commercial CD-DVD optical pickup unit (OPU) mounted on a controllable platform [15]. It also allows for the precise control of laser power density and dwell time to

Low cost, p-ZnO/n-Si, rectifying, nano heterojunction diode: Fabrication and electrical characterization

• Vinay Kabra,
• Lubna Aamir and
• M. M. Malik

Beilstein J. Nanotechnol. 2014, 5, 2216–2221, doi:10.3762/bjnano.5.230

• concentrations of dopant, but these results were not suitable for the above atomic ratio, which was determined after optimization. Device fabrication The p-type ZnO thin film was formed on the n-type Si substrate using a dip coating technique with an immersion rate of 9 mm/s, a dwell time of 20 s, and a

Highly NO₂ sensitive caesium doped graphene oxide conductometric sensors

• Carlo Piloto,
• Marco Notarianni,
• Mahnaz Shafiei,
• Elena Taran,
• Dilini Galpaya,
• Cheng Yan and
• Nunzio Motta

Beilstein J. Nanotechnol. 2014, 5, 1073–1081, doi:10.3762/bjnano.5.120

• radiation was monochromatic Al Kα X-rays (1486.6 eV) at 225 W (15 kV, 15 mA). Survey (wide) scans were taken at analyser pass energy of 160 eV and multiplex (narrow) high resolution scans at 20 eV. Survey scans were carried out over 1200–0 eV binding energy range with 1.0 eV steps and a dwell time of 100 ms

• . Narrow high-resolution scans were run with 0.05 eV steps and 250 ms dwell time. Base pressure in the analysis chamber was kept at 1.0 × 10−9 Torr and during sample analysis 1.0 × 10−8 Torr. Peak fitting of the high-resolution data was also carried out using the CasaXPS software. Raman spectroscopy was

Fabrication of carbon nanomembranes by helium ion beam lithography

• Xianghui Zhang,
• Henning Vieker,
• André Beyer and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2014, 5, 188–194, doi:10.3762/bjnano.5.20

• to observe the development of the crosslinking of the SAM, the NBPT SAM was irradiated in circular regions by helium ion beam with a series of different doses. The variations of the irradiation dose are achieved by controlling the dwell time of the beam. Provided that the fabrication conditions are

• performed by using the built-in software. The ion beam is programmed to irradiate an array of circular features by using a bitmap file and the dose variations are achieved by controlling the dwell time per pixel. The helium ion beam was operated at an acceleration voltage of 34.8 kV and a current of 3.5 pA

• on SiO2 were acquired at a working distance of 9 mm and a tilt angle of 35° with 30 µs dwell time per pixel. Images on grid were acquired at a working distance of 30 mm with 0.5 µs dwell time and 128 frames averaged. Transfer of carbon nanomembranes After helium ion irradiation, the whole NBPT CNMs

In situ growth optimization in focused electron-beam induced deposition

• Paul M. Weirich,
• Marcel Winhold,
• Christian H. Schwalb and
• Michael Huth

Beilstein J. Nanotechnol. 2013, 4, 919–926, doi:10.3762/bjnano.4.103

• achieved with the GA by solely varying the process parameters pitch p and dwell-time tD in the deposition process. The precursor-specific limitations of the approach are also exemplified for another precursor, MeCpPt(Me)3, which is known to show only one bond-cleavage in the initial step [18]. This results

• process, the set of parameters used for the deposition of one specific layer consists of the x- and y-size of the deposit, the dwell time (tD), the pitch in x (px) and y (py) direction, the beam current (I), the acceleration voltage (U), the temperature (T), refresh-time (tr), scan-type (raster or

• parameter sets. The measured rate of change of conductance during the FEBID process for the reference sample is displayed in Figure 3a (Sample 1). Subsequently the GA was applied for finding the optimized parameters for the deposition that used W(CO)6 as a precursor. First, only the dwell time tD was used

Dynamic nanoindentation by instrumented nanoindentation and force microscopy: a comparative review

• Sidney R. Cohen and
• Estelle Kalfon-Cohen

Beilstein J. Nanotechnol. 2013, 4, 815–833, doi:10.3762/bjnano.4.93

• viscoelastic/plastic deformation, as well as capillary and adhesive forces. The analysis of AFM force–distance curves of polydimethylsiloxane (PDMS) showed a strong influence of the measurement conditions such as the loading–unloading rate and the dwell time, as well as intrinsic material properties like the

Ultramicrosensors based on transition metal hexacyanoferrates for scanning electrochemical microscopy

• Maria A. Komkova,
• Angelika Holzinger,
• Andreas Hartmann,
• Alexei R. Khokhlov,
• Christine Kranz,
• Arkady A. Karyakin and
• Oleg G. Voronin

Beilstein J. Nanotechnol. 2013, 4, 649–654, doi:10.3762/bjnano.4.72

• deposited onto a microelectrode using a focused ion beam gas-assisted process (Quanta 3D FEG, FEI Eindhoven). The circular Pt/C composite were deposited on 10 µm Pt electrodes and had a radius of approx. 6.5 µm and a thickness of approx. 150 nm (ion beam current: 300 pA and a dwell time of 200 ns) with a

The role of electron-stimulated desorption in focused electron beam induced deposition

• Willem F. van Dorp,
• Thomas W. Hansen,
• Jakob B. Wagner and
• Jeff T. M. De Hosson

Beilstein J. Nanotechnol. 2013, 4, 474–480, doi:10.3762/bjnano.4.56

• given in Table 1 and range between 1 and 6 pA, which is consistent with values reported in literature [20][21]. Figure 1b shows the average deposited mass per dot as a function of beam current and substrate temperature. In this case the dwell time was 3 s per dot for all arrays. From the fact that the

• deposited mass increases with the beam current, we conclude that the growth is electron-limited at all substrate temperatures. The effect of the dwell time is studied by writing arrays of dots with spot 9 at three temperatures, 306 K, 341 K and 371 K. The average deposited mass per dot is plotted as a

• function of the dwell time in Figure 2a (see below), from which Edes can be determined. Following the model proposed by Müller et al. [22], the precursor coverage, N·(cm−2), depends on the adsorption from the gas phase, the diffusion of precursor molecules over the surface, the number of molecules consumed

Digging gold: keV He⁺ ion interaction with Au

• Vasilisa Veligura,
• Gregor Hlawacek,
• Robin P. Berkelaar,
• Raoul van Gastel,
• Harold J. W. Zandvliet and
• Bene Poelsema

Beilstein J. Nanotechnol. 2013, 4, 453–460, doi:10.3762/bjnano.4.53

• was oriented perpendicular to the surface. Three primary ion energies were used in the experiments: 15, 25 and 35 keV. The images were recorded with 0.68 nm pixel spacing, 2 μs dwell time and 32-line averaging, giving an ion dose per image of 6 × 1016 cm−2. The chamber base pressure during imaging was