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

Porous polymer coatings as substrates for the formation of high-fidelity micropatterns by quill-like pens

• Michael Hirtz,
• Marcus Lyon,
• Wenqian Feng,
• Andrea E. Holmes,
• Harald Fuchs and
• Pavel A. Levkin

Beilstein J. Nanotechnol. 2013, 4, 377–384, doi:10.3762/bjnano.4.44

• ). After filling of the reservoir on the SPT with the dye solution, it is brought into contact with the substrate surface for a defined dwell time to allow a flow to the substrate by capillary forces. The SPT is retracted and moved to the next spotting position. The process of relocation, contacting and

• retracting is repeated until the desired spot features are created. The writing procedure can be relatively fast: our standard pattern of 100 spots arranged in a square with pitch of 50 µm (yielding a patterned area of 500 × 500 µm2) with a dwell time of 0.5 s was written with a single cantilever in about a

• platforms for the microarray spotting using SPTs. A pattern of 10 × 10 spots with a 50 µm pitch and dwell time of 0.5 s was written on each of the substrates by using a 10 mM solution of phloxine B in isopropanol mixed with 30 vol % glycerol (87% in water) to prevent drying of the dye solution in the SPT

Low-dose patterning of platinum nanoclusters on carbon nanotubes by focused-electron-beam-induced deposition as studied by TEM

• Xiaoxing Ke,
• Carla Bittencourt,
• Sara Bals and
• Gustaaf Van Tendeloo

Beilstein J. Nanotechnol. 2013, 4, 77–86, doi:10.3762/bjnano.4.9

• is studied by changing the beam accelerating voltage (primary energy, PE) and dwell time, whereas the beam current is not varied in the current study. Figure 6 summarizes the deposition of Pt for an increasing PE of 1 kV, 3 kV, 5 kV, 10 kV, 15 kV and 30 kV in each row. For each PE, different dwell

• distribution. Comparing the nanoclusters in the same column in which PE is increasing and dwell time is not varied, it can be seen that their average size and lateral density decreases. The higher lateral density indicates a higher dissociation probability at lower PE, where PE contributes more to the

• constant and dwell time is increased, it is noticed that the change in lateral density of the nanoclusters does not follow the same trend. When PE is 1 kV and 3 kV, the deposited nanoclusters have the same high density for all dwell times from 50 ns to 10 μs. Nevertheless, when PE is 15 kV and 30 kV, the

Growth behaviour and mechanical properties of PLL/HA multilayer films studied by AFM

• Cagri Üzüm,
• Johannes Hellwig,
• Narayanan Madaboosi,
• Dmitry Volodkin and
• Regine von Klitzing

Beilstein J. Nanotechnol. 2012, 3, 778–788, doi:10.3762/bjnano.3.87

• velocity, but unlike a standard elasticity measurement, the indenter was not retracted instantly after the initial indentation. It was left to dwell in the film while the z-piezo drive was paused. The AFM detector continued collecting the cantilever deflection data F as a function of time t. The dwell time

• (“Relaxation” in Figure 9, viscous response). After 40 s (“Dwell Time” in Figure 9) the cantilever was retracted from the film, as in the case of a standard elasticity measurement (“Retraction” in Figure 9). Data points were collected every 0.1 s. Typical F versus t relaxation curves on (PLL/HA)72 are

• is stopped. “End of dwell” shows the maximum indentation depth caused by the relaxation on the cantilever. Stress relaxation curve with a dwell time of 40 s. The biexponential fit is represented by the thick lines on the decaying part of the force curve, in the dwell regime. The cantilever’s stress

Focused electron beam induced deposition: A perspective

• Michael Huth,
• Fabrizio Porrati,
• Christian Schwalb,
• Marcel Winhold,
• Roland Sachser,
• Maja Dukic,
• Jonathan Adams and
• Georg Fantner

Beilstein J. Nanotechnol. 2012, 3, 597–619, doi:10.3762/bjnano.3.70

• independently controlled, is analyzed within a continuum model of FEBID that employs rate equations. Predictions are made for the tunability of the composition of the Co–Pt system by simply changing the dwell time of the electron beam during the writing process. The charge-transport regimes of nanogranular

• govern the writing process are the primary-beam energy E and beam current I, the time for which the electron beam is held constant on a particular point on the surface, the dwell time tD, the distance between neighboring dwell points, the pitch p, and the number of loops for which the writing pattern is

• [22] where J is the precursor flux modified by the sticking coefficient s. The local growth rate R(r) of the deposit, assuming the volume V for the nonvolatile dissociation product of an individual precursor molecule, is then obtained from with tD denoting the beam dwell time. Valuable insight can be

Nano-structuring, surface and bulk modification with a focused helium ion beam

• Daniel Fox,
• Yanhui Chen,
• Colm C. Faulkner and
• Hongzhou Zhang

Beilstein J. Nanotechnol. 2012, 3, 579–585, doi:10.3762/bjnano.3.67

• process as sample 1. Sample 3 is a silicon sample; it was treated with an extra final step. The sample face was tilted 2° into the beam and scanned with reduced energy gallium beam of 5 keV for one minute on each side, the beam current was 20 pA. A short dwell time and a large number of scan repeats were

• was 1.2 pA. The beam was rastered in a single scan over the area with a pixel spacing of 1 nm and a dwell time at each point of 1.3 × 10−3 s. The sample was rotated through 180° and the process was repeated on the opposite sidewall. The scanning time per sidewall was 68 s. This section of the sample

• × 200 nm area was exposed to a dose of 6.2 × 1018 ions/cm2. The beam current used was 3.4 pA. The beam was rastered in a single scan over the area with a pixel spacing of 0.7 nm and a dwell time at each point of 5 × 10−3 s. The total scanning time was 612 s. This process produced a hole straight through

Spontaneous dissociation of Co₂(CO)₈ and autocatalytic growth of Co on SiO₂: A combined experimental and theoretical investigation

• Kaliappan Muthukumar,
• Harald O. Jeschke,
• Roser Valentí,
• Evgeniya Begun,
• Johannes Schwenk,
• Fabrizio Porrati and
• Michael Huth

Beilstein J. Nanotechnol. 2012, 3, 546–555, doi:10.3762/bjnano.3.63

• pregrowth irradiated with a focused electron beam, which was moved in a raster fashion (dwell time 100 μs, pitch 20 nm) for 30 min over a rectangular region of 3.7 × 1.0 μm2 bridging the gap between two prepatterned Cr/Au electrodes. The background pressure during the irradiation process was 6 × 10−6 mbar

Distinguishing magnetic and electrostatic interactions by a Kelvin probe force microscopy–magnetic force microscopy combination

• Miriam Jaafar,
• Oscar Iglesias-Freire,
• Luis Serrano-Ramón,
• Manuel Ricardo Ibarra,
• Jose Maria de Teresa and
• Agustina Asenjo

Beilstein J. Nanotechnol. 2011, 2, 552–560, doi:10.3762/bjnano.2.59

• ]. All the structures presented in this study were deposited with an electron beam current of 2.1 nA, an acceleration voltage of 10 kV and 1 µs dwell time. The nanowires grown by this technique are polycrystalline with grain sizes of a few nanometers oriented randomly, thus shape anisotropy is the main