Low temperature atomic layer deposition of cobalt using dicobalt hexacarbonyl-1-heptyne as precursor

• Mathias Franz,
• Mahnaz Safian Jouzdani,
• Lysann Kaßner,
• Marcus Daniel,
• Frank Stahr and
• Stefan E. Schulz

Beilstein J. Nanotechnol. 2023, 14, 951–963, doi:10.3762/bjnano.14.78

• dicobalt hexacarbonyl tert-butylacetylene (CCTBA) can be used to deposit metallic cobalt in the temperature range from 125 to 200 °C [15]. As an exception, Kim et al. have reported the ALD of Co with Co2(CO)8 in the temperature range of 70 to 110 °C. However, this process resulted in a significant carbon

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

• for organic and metal-organic substrates the activation mechanism is still not fully understood [14][15][16][17]. So far, EBISA was effective with the precursors Fe(CO)5 and Co(CO)3NO in UHV [12][14][15][16][17][18][20] and Co2(CO)8 in high vacuum (HV) [13]. The purity of substantial deposits in EBISA

Magnetic characterization of cobalt nanowires and square nanorings fabricated by focused electron beam induced deposition

• Federico Venturi,
• Gian Carlo Gazzadi,
• Amir H. Tavabi,
• Alberto Rota,
• Rafal E. Dunin-Borkowski and
• Stefano Frabboni

Beilstein J. Nanotechnol. 2018, 9, 1040–1049, doi:10.3762/bjnano.9.97

• focused electron beam induced deposition (FEBID) of Co carbonyl (Co2(CO)8). This is a direct-write technique performed in a scanning electron microscope (SEM) equipped with a gas injector system (GIS) [9]. It exploits secondary electron emission resulting from interaction of the primary electron beam with

• (Co2(CO)8) precursor and characterized magnetically using both TEM and MFM. EH measurements on as-deposited NWs revealed single-magnetic-domain states, with a higher magnetic signal for 5 keV deposition than for 15 keV deposition. This difference is thought to result from both a greater relative Co

Electron interactions with the heteronuclear carbonyl precursor H₂FeRu₃(CO)₁₃ and comparison with HFeCo₃(CO)₁₂: from fundamental gas phase and surface science studies to focused electron beam induced deposition

• Ragesh Kumar T P,
• Paul Weirich,
• Lukas Hrachowina,
• Marc Hanefeld,
• Ragnar Bjornsson,
• Helgi Rafn Hrodmarsson,
• Sven Barth,
• D. Howard Fairbrother,
• Michael Huth and
• Oddur Ingólfsson

Beilstein J. Nanotechnol. 2018, 9, 555–579, doi:10.3762/bjnano.9.53

• vapor pressure. For instance, Fe(CO)5, [51][52] Fe2(CO)9 [53][54] and Co2(CO)8 [55] have been shown to yield deposits with high metal content (>60 atom %). In addition, high resolution FEBID of metal nanostructures below 30 nm [56] and successful 3D growth [57] has been demonstrated; however

Electron interaction with copper(II) carboxylate compounds

• Michal Lacko,
• Peter Papp,
• Iwona B. Szymańska,
• Edward Szłyk and
• Štefan Matejčík

Beilstein J. Nanotechnol. 2018, 9, 384–398, doi:10.3762/bjnano.9.38

• purities of W from 55 to 70% [6][7]. For comparison, the deposition of cobalt from Co(CO)3(NO) leads to around 50% purity [8] or satisfying purity over 95% using the dimer Co2(CO)8 [9]. Only few types of precursor molecules can be converted into a layer with satisfying level of purity, for other elements

Comparative study of post-growth annealing of Cu(hfac)₂, Co₂(CO)₈ and Me₂Au(acac) metal precursors deposited by FEBID

• Marcos V. Puydinger dos Santos,
• Aleksandra Szkudlarek,
• Artur Rydosz,
• Carlos Guerra-Nuñez,
• Fanny Béron,
• Kleber R. Pirota,
• Stanislav Moshkalev,
• José Alexandre Diniz and
• Ivo Utke

Beilstein J. Nanotechnol. 2018, 9, 91–101, doi:10.3762/bjnano.9.11

• annealing protocol at 100, 200, and 300 °C under high vacuum on deposits obtained from Co2(CO)8, Cu(II)(hfac)2, and Me2Au(acac) to study improvements on composition and electrical conductivity. Although the as-deposited material was similar for all precursors, metal grains embedded in a carbonaceous matrix

• -pixel distance. Dicobalt octacarbonyl [Co2(CO)8], bis(hexafluoroacetylacetonato)copper(II) [Cu(hfac)2, Cu(HC5O2F6)2] and dimethyl(acetylacetonato)gold(III) [Me2Au(acac), (CH3)2Au(C5H7O2)] were employed as precursors, with average fluxes of 4.1 × 1018, 2.9 × 1017 and 3.6 × 1017 molecules·s−1·cm−2

• . Values of about 1, 10, and 10 electrons per impinging precursor molecule, respectively, for Co2(CO)8, Cu(hfac)2 and Me2Au(acac), were inferred from the calculated electronic flux, which we supposed to be close to the electron-limited regime. The chamber pressure during FEBID experiments was maintained at

The rational design of a Au(I) precursor for focused electron beam induced deposition

• Ali Marashdeh,
• Thiadrik Tiesma,
• Niels J. C. van Velzen,
• Sjoerd Harder,
• Remco W. A. Havenith,
• Jeff T. M. De Hosson and
• Willem F. van Dorp

Beilstein J. Nanotechnol. 2017, 8, 2753–2765, doi:10.3762/bjnano.8.274

• precursors are Co2(CO)8 [38][39][40], Fe(CO)5 [41][42][43] and HFeCo3(CO)12 [44]. These precursors yield deposits with a high metal content, given the right deposition conditions. W(CO)6 is basically too stable, resulting in a high contents of C and O in the deposit [28]. Ni(CO)4 on the other hand is too

Comparing postdeposition reactions of electrons and radicals with Pt nanostructures created by focused electron beam induced deposition

• Julie A. Spencer,
• Michael Barclay,
• Miranda J. Gallagher,
• Robert Winkler,
• Ilyas Unlu,
• Yung-Chien Wu,
• Harald Plank,
• Lisa McElwee-White and
• D. Howard Fairbrother

Beilstein J. Nanotechnol. 2017, 8, 2410–2424, doi:10.3762/bjnano.8.240

• postdeposition purification strategy where FEBID structures created from Co2(CO)8 were annealed to 300 °C and exposed to H2 and electron irradiation leading to the formation of compact, carbon- and oxygen-free 20 nm thick Co layers [43]. As a means of comparison, the effect of AH on other contaminant elements

Modelling focused electron beam induced deposition beyond Langmuir adsorption

• Dédalo Sanz-Hernández and
• Amalio Fernández-Pacheco

Beilstein J. Nanotechnol. 2017, 8, 2151–2161, doi:10.3762/bjnano.8.214

• physi-adsorption when E1 ≠ E2. This is essential when working on surfaces which may be chemically activated by electron irradiation [48]. Chemisorbed adsorbates are common, for instance, when using FEBID precursors leading to highly metallic deposits, such as Co2(CO)8, Co(CO)3NO and Fe(CO)5, where

• temperature. Examples of ν2, νe and νGAS values for standard experimental FEBID conditions. σ = 5·10−21 m2 for Co2(CO)8 is used from [19]. F is calculated for a Helios FEI dual beam system with a Pfeiffer TMH 262 turbo-molecular pump. Typical vaporization enthalpy values for FEBID precursors, associated to E2

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

• ]. Cobalt tricarbonyl nitrosyl has a normal boiling point of 78.6 °C, a vapor pressure of 91 Torr at 20 °C [79], and a thermal decomposition temperature of about 130–140 °C measured on SiO2 [80]. It is also commercially available and relatively nontoxic. Furthermore, the commonly used Co precursor Co2(CO)8

• exposure, and electron irradiation of deposits formed with Co2(CO)8 was found to result in compact, carbon and oxygen free Co layers [84]. In a 2011 gas phase study, Engmann et al. [24] published absolute cross section values for DEA to Co(CO)3NO. These were the first absolute cross section values

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

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

• atom % of Au (rt) to 24 atom % of Au (at 100 °C). Increasing the substrate temperature during FEBID also favors the desorption of non-metallic dissociation by-products as it was observed by Mulders et al. [31] for various precursors: TEOS (tetraethylorthosilicate), Co(CO)3NO, Co2(CO)8, and Me2Au(acac

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

• –carbonyl precursor (Co2(CO)8) by focused electron beam induced deposition (FEBID). The SNWs dimensions are about 30–50 nm in diameter and 600–850 nm in length. The as-deposited material has a nanogranular structure of mixed face-centered cubic (FCC) and hexagonal close-packed (HCP) Co phases, and a

• and electromigration effects [21][22] come into play and are a major cause of failures. In this work, we deposit free-standing suspended nanowires (SNWs) using Co–carbonyl precursor (Co2(CO)8), and study their behavior under high electrical current density, following the same approach used for Pt

• Strata DB235M) combining a Ga-ion focused ion beam (FIB) with a thermal field emission SEM, equipped with a Co–carbonyl (Co2(CO)8) GIS operated at room temperature (RT). The GIS is mounted at a polar angle of 52° and an azimuthal angle of 115° with respect to the sample surface. An injection nozzle with

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

• photomask repair [20] to fabrication of nanowires [17][21], nanopores [22], magnetic [5][12] and strain sensors [23] as well as direct-write superconductors [24]. The precursors Co2(CO)8 and (CH3)3CH3PtC5H4 from which Pt- an Co-based structures can be fabricated in the FEBID process, like most metal-organic

• 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

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

• , for instance: WF6 [4], Co2(CO)8 [5], and AuClPF3 [6]; 2) mixed gas chemistries which react with the typically organic fragments [7][8] and 3) in situ substrate [9][10] or pulsed laser heating [11][12][13]. Several ex situ strategies have also been explored. Post annealing treatments in various

Electron-beam induced deposition and autocatalytic decomposition of Co(CO)₃NO

• Florian Vollnhals,
• Martin Drost,
• Fan Tu,
• Esther Carrasco,
• Andreas Späth,
• Rainer H. Fink,
• Hans-Peter Steinrück and
• Hubertus Marbach

Beilstein J. Nanotechnol. 2014, 5, 1175–1185, doi:10.3762/bjnano.5.129

• products remain on the surface as a deposit. Some materials can be deposited with high purity, e.g., iron from iron pentacarbonyl, Fe(CO)5 [6][7][8][9], cobalt from dicobalt octacarbonyl, Co2(CO)8 [10][11], or Au from Au(CO)Cl [12]. In addition, EBID offers the advantage of very small obtainable structure

• of the previous EBISA studies as well as some EBID studies used Fe(CO)5 as precursor, which yields practically pure, (poly-)crystalline Fe on different substrates [7][8][16][17][18][19]. In addition, Co2(CO)8 was also identified as a suitable precursor for EBISA in experimental work on silica

• surfaces in a high-vacuum environment [15]. Since other precursors may show a similar behavior, we investigated one relevant candidate concerning autocatalytic growth, namely cobalt tricarbonyl nitrosyl, Co(CO)3NO, in more detail. This precursor is more stable and easier to handle than the related Co2(CO)8

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

• success of the GA-optimization process is due to the fact that the metal content of the deposits can be tuned over a wide range and that it strongly depends on the deposition parameters, which is known to be the case for many carbonyl-based precursors (e.g., W(CO)6 [10][19][21], Co2(CO)8 [2][22] and Fe(CO

Hydrogen-plasma-induced magnetocrystalline anisotropy ordering in self-assembled magnetic nanoparticle monolayers

• Alexander Weddemann,
• Judith Meyer,
• Anna Regtmeier,
• Irina Janzen,
• Dieter Akemeier and
• Andreas Hütten

Beilstein J. Nanotechnol. 2013, 4, 164–172, doi:10.3762/bjnano.4.16

• sample I, 65 µL (0.2 mmol) oleylamine was dissolved in 4 mL 1,2-dichlorobenzene. The solution was subsequently heated under reflux. Separately, 150 mg (0.44 mmol) dicobaltoctacarbonyl Co2(CO)8 was dissolved in 2 mL of 1,2-dichlorobenzene. During vigorous stirring, the second solution was rapidly injected

• mmol) dicobaltoctacarbonyl Co2(CO)8 was dissolved in 2 mL of 1,2-dichlorobenzene and rapidly injected into the refluxing bath. After a reaction time of 15 min, the mixture was cooled to room temperature. Due to the different surfactants present during the particle formation, particles in sample I are

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

• alkanes, silanes, metal halogens, carbonyls, phosphines, acetylacetonates and so forth. In the following the focus is on organometallic precursors. Popular representatives for the transition metals are carbonyls, such as W(CO)6 or Co2(CO)8, but also more complex precursors, such as Me3Pt(IV)CpMe. For

• yet [12]. Also with regard to sensor applications nanogranular materials prepared by FEBID hold great promise. These aspects will be discussed in later chapters of this review. For selected precursors, such as Co2(CO)8 [13], Fe(CO)5 [14][15] and also AuClPF3 [16], polycrystalline deposits can be

• , Co2(CO)8 was used at a flux of J1 = 1.5 × 1017 (cm2s)−1 (see Figure 3 for molecular models of the precursors). In independent octanol-free calibration measurements, the elemental composition was found to be Co2C0.6O0.4, i.e., a Co–Content of 66 atom %. Deposits from the residual gas contained carbon

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

• Frankfurt am Main, Germany present address: Empa, CH-8600 Dübendorf, Switzerland 10.3762/bjnano.3.63 Abstract We present experimental results and theoretical simulations of the adsorption behavior of the metal–organic precursor Co2(CO)8 on SiO2 surfaces after application of two different pretreatment steps

• dissociation of the precursor molecule. In view of these calculations, we discuss the origin of this dissociation and the subsequent autocatalysis. Keywords: Co2(CO)8; deposition; dissociation; EBID; FEBID; precursor; radiation-induced nanostructures; Introduction In recent years, focused electron beam

• (chloroplatinic acid) [10] are used to deposit metals or metal composites on selected regions of the substrates. Deposits with a wide spectrum of properties and composition can be consequently obtained due to the availability of suitable precursors [1][2]. Co2(CO)8 has been recently used as a precursor molecule

Improvement of the oxidation stability of cobalt nanoparticles

• Celin Dobbrow and
• Annette M. Schmidt

Beilstein J. Nanotechnol. 2012, 3, 75–81, doi:10.3762/bjnano.3.9

• size and properties of the stabilizer molecule on the observed deceleration, and finally stagnation, of the isothermal oxidation process in air. The particles in this study were synthesized by thermolysis of dicobalt octacarbonyl (Co2(CO)8) in the presence of a fatty acid (oleic acid or ricinolic acid

• during the thermolysis of Co2(CO)8 with carboxylic acid-telechelic polystyrene, which was obtained by atom transfer radical polymerization (ATRP) [14] (see Supporting Information File 1 for details). All synthetic steps involved were performed under argon in order to prevent premature oxidation. The

• shell was performed by thermolysis of Co2(CO)8 in the presence of carboxylic acid-telechelic polystyrene [14]. Co@PS particles were exposed to isothermal oxidation in air at 25 °C, both in toluene dispersion and as a powder. While the curves demonstrate the same general shape as already observed for

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

• Discussion In the present work we have studied cobalt nanowires grown by focused-electron-beam-induced deposition (FEBID). The sample growth was performed in a commercial dual beam® equipment using a field emission scanning electron microscope with Co2(CO)8 as gas precursor. The substrate material used in

• on average less energetic. Therefore, the decomposition of the precursor gas (Co2(CO)8) in the halo is not complete. As a consequence, the halo is an insulating material of which the major components are C and O (the Co content in the halo is lower than 20% in our system). Previous works have