Focused ion and electron beams for synthesis and characterization of nanomaterials

• Aleksandra Szkudlarek

Beilstein J. Nanotechnol. 2025, 16, 613–616, doi:10.3762/bjnano.16.47

• deposition techniques, this thematic issue includes studies on low-energy electron interactions with metal(II) bis(acetylacetonate) complexes [5]. Another molecule investigated for its gas-phase fragmentation mechanism via dissociative ionization and dissociative electron attachment is [Au(CH3)2Cl]2. Studies

Ion-induced surface reactions and deposition from Pt(CO)₂Cl₂ and Pt(CO)₂Br₂

• Mohammed K. Abdel-Rahman,
• Patrick M. Eckhert,
• Atul Chaudhary,
• Johnathon M. Johnson,
• Jo-Chi Yu,
• Lisa McElwee-White and
• D. Howard Fairbrother

Beilstein J. Nanotechnol. 2024, 15, 1427–1439, doi:10.3762/bjnano.15.115

• the metal of interest. Furthermore, as the volatile species escape the system, they can collide with adsorbed material leading to a cascade of momentum transfer events [43]. In contrast to FIBID, FEBID occurs via different electron stimulated mechanisms, namely, dissociative electron attachment (DEA

• the formation of PtCl2, although in the case of electron irradiation this initial step was ascribed to dissociative electron attachment as opposed to momentum transfer [57]: At much higher electron doses, Cl was removed by electron stimulated desorption to convert PtCl2 to Pt: However, to achieve

Electron-induced ligand loss from iron tetracarbonyl methyl acrylate

• Hlib Lyshchuk,
• Atul Chaudhary,
• Thomas F. M. Luxford,
• Miloš Ranković,
• Jaroslav Kočišek,
• Juraj Fedor,
• Lisa McElwee-White and
• Pamir Nag

Beilstein J. Nanotechnol. 2024, 15, 797–807, doi:10.3762/bjnano.15.66

• and support the interpretation of data by quantum chemical calculations. This way, both the dissociative ionization and dissociative electron attachment fragmentation channels are characterized. Considerable differences in the degree of precursor fragmentation in these two channels are observed

• the gas phase has been probed with respect to its dissociative ionization [10] and dissociative electron attachment [11][12]; there is even information available on its electronic excitation, which is the first step towards neutral dissociation [11]. The gas-phase studies have been complemented by

• advanced reactive force field molecular dynamics simulations [20]. Here we focus on two electron-induced dissociative channels of Fe(CO)4MA, namely, dissociative ionization and dissociative electron attachment (DEA). We focus on the electron energy range below 20 eV. Data from two complementary

Sidewall angle tuning in focused electron beam-induced processing

• Sangeetha Hari,
• Willem F. van Dorp,
• Johannes J. L. Mulders,
• Piet H. F. Trompenaars,
• Pieter Kruit and
• Cornelis W. Hagen

Beilstein J. Nanotechnol. 2024, 15, 447–456, doi:10.3762/bjnano.15.40

• modification – proof of principle simulation Low-energy electrons are assumed to be most effective in the dissociation process. The reason is that low-energy electrons interact more efficiently with molecules than high-energy electrons. One dissociation channel is dissociative electron attachment (DEA), which

A combined gas-phase dissociative ionization, dissociative electron attachment and deposition study on the potential FEBID precursor [Au(CH₃)₂Cl]₂

• Elif Bilgilisoy,
• Ali Kamali,
• Thomas Xaver Gentner,
• Gerd Ballmann,
• Sjoerd Harder,
• Hans-Peter Steinrück,
• Hubertus Marbach and
• Oddur Ingólfsson

Beilstein J. Nanotechnol. 2023, 14, 1178–1199, doi:10.3762/bjnano.14.98

• removed per dissociative ionization incident. On the other hand, in dissociative electron attachment, no chlorine was removed from the parent molecule. Contrary to these observations, FEBID in the UHV setup was found to yield a quantitative loss and desorption of the chlorine from the deposits, an effect

• yielded deposits with high gold content, ranging from 45 to 61 atom % depending on the beam current and on the cleanliness of the substrates surface. Keywords: dissociative electron attachment; dissociative ionization; focused-electron-beam-induced deposition (FEBID); gold deposit; low-energy electrons

• , which in turn is critical to the resulting purity of the FEBID deposits. In general, electron-induced fragmentation processes are categorized as dissociative ionization (DI), dissociative electron attachment (DEA), dipolar dissociation (DD), and neutral dissociation (ND) [25]. To fully comprehend the

Fragmentation of metal(II) bis(acetylacetonate) complexes induced by slow electrons

• Janina Kopyra and
• Hassan Abdoul-Carime

Beilstein J. Nanotechnol. 2023, 14, 980–987, doi:10.3762/bjnano.14.81

• attachment. The reported data may contribute to a better understanding of the physical chemistry underlying the electron–molecule interactions, which is crucial for potential applications of these molecular systems in the deposition of nanoscale structures. Keywords: dissociative electron attachment; gas

• fragmentation arises from a resonant mechanism known as dissociative electron attachment (DEA) producing exclusively a negative fragment ion and one or more neutral counterparts, as it will be discussed below. The contribution of each of the processes may depend on the nature of the organometallic precursors

• electron energy range investigated in the present work, that is, below 10 eV, DEA, as well as neutral dissociation and dissociative ionization, are the mechanisms responsible for the efficient fragmentation of molecules. In the case of dissociative electron attachment, studied in the present work, the

Investigation of electron-induced cross-linking of self-assembled monolayers by scanning tunneling microscopy

• Patrick Stohmann,
• Sascha Koch,
• Yang Yang,
• Christopher David Kaiser,
• Julian Ehrens,
• Jürgen Schnack,
• Niklas Biere,
• Dario Anselmetti,
• Armin Gölzhäuser and
• Xianghui Zhang

Beilstein J. Nanotechnol. 2022, 13, 462–471, doi:10.3762/bjnano.13.39

• between neighboring aromatic molecules. The mechanisms of cross-linking are dependent on the electron energy: below the ionization potential, a two-step resonant dissociative electron attachment (DEA) has been proposed [5][60][61][62]. Based on HREELS data, Amiaud et al. proposed a resonant electron

• initiates a reaction with an adjacent molecule and generates another new radical carbon center, which may react with other molecules. According to Amiaud et al. [53], the formation of first radicals can be caused either by electronic rearrangement or dissociative electron attachment of the negative ion

Low-energy electron interaction and focused electron beam-induced deposition of molybdenum hexacarbonyl (Mo(CO)₆)

• Po-Yuan Shih,
• Maicol Cipriani,
• Christian Felix Hermanns,
• Jens Oster,
• Klaus Edinger,
• Armin Gölzhäuser and
• Oddur Ingólfsson

Beilstein J. Nanotechnol. 2022, 13, 182–191, doi:10.3762/bjnano.13.13

• , University of Iceland, Dunhagi 3, 107 Reykjavik, Iceland 10.3762/bjnano.13.13 Abstract Motivated by the potential role of molybdenum in semiconductor materials, we present a combined theoretical and experimental gas-phase study on dissociative electron attachment (DEA) and dissociative ionization (DI) of Mo

• studies on W(CO)6 and we hypothesize that reductive ligand loss through electron attachment may promote metal–metal bond formation in the deposition process, leading to further ligand loss and the high metal content observed in FEBID for both these compounds. Keywords: dissociative electron attachment

• ]. In general, there are four distinct electron-induced processes that lead to molecular fragmentation [13]. These are dissociative electron attachment (DEA), dissociative ionization (DI), neutral dissociation (ND) and dipolar dissociation (DD). The processes differ distinctly in their energy dependence

Irradiation-driven molecular dynamics simulation of the FEBID process for Pt(PF₃)₄

• Alexey Prosvetov,
• Alexey V. Verkhovtsev,
• Gennady Sushko and
• Andrey V. Solov’yov

Beilstein J. Nanotechnol. 2021, 12, 1151–1172, doi:10.3762/bjnano.12.86

• including possible mechanisms of irradiation-induced molecular fragmentation can be found, for example, in [42]. The main mechanisms of precursor fragmentation are dissociative electron attachment (DEA) at low electron energies below the ionization potential of the molecule and dissociative ionization (DI

Chemistry for electron-induced nanofabrication

• Petra Swiderek,
• Hubertus Marbach and
• Cornelis W. Hagen

Beilstein J. Nanotechnol. 2018, 9, 1317–1320, doi:10.3762/bjnano.9.124

• )) at energies above the ionization threshold while dissociative electron attachment (DEA) occurs already at near-thermal electron energies. Experiments reported in this Thematic Series have aimed at unraveling the role of these processes in FEBID [20]. They use cyclic silane precursors in which DEA has

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

• carbonyl complex H2FeRu3(CO)13 covering its low energy electron induced fragmentation in the gas phase through dissociative electron attachment (DEA) and dissociative ionization (DI), its decomposition when adsorbed on a surface under controlled ultrahigh vacuum (UHV) conditions and exposed to irradiation

• induced decomposition of this precursor and how this is reflected in the relatively poor performance of H2FeRu3(CO)13 as compared to the structurally similar HFeCo3(CO)12. Keywords: dissociative electron attachment; dissociative ionization; electron induced deposition; electron molecule interaction

• by four distinctly different processes, which are active within different energy ranges, and more importantly, lead to distinctly different processes; dissociative electron attachment (DEA), dissociative ionization (DI), and neutral and dipolar dissociation upon electron excitation (ND and DD). An

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

• the evaporation of whole complex molecules. A significant production of Cu+ ion was observed only for [Cu2(µ-O2CC2F5)4], a weak yield was detected for [Cu2(EtNH2)2(µ-O2CC2F5)4] as well. The dissociative electron attachment processes leading to formation of negative ions are similar for all

• fragments of these complexes are formed through single particle resonant processes close to 0 eV. Keywords: amines; dissociative electron attachment; dissociative ionization; FEBID; low energy electrons interaction; Introduction Present technological changes require the development of new methods and new

• . High energy electrons have low interaction cross section with the target molecule; their interaction efficiency is therefore very low. Secondary electrons, on the other hand, play important role through electron attachment (EA), dissociative electron attachment (DEA) [10][11][12][13][14][15][16] and

Electron-driven and thermal chemistry during water-assisted purification of platinum nanomaterials generated by electron beam induced deposition

• Ziyan Warneke,
• Markus Rohdenburg,
• Jonas Warneke,
• Janina Kopyra and
• Petra Swiderek

Beilstein J. Nanotechnol. 2018, 9, 77–90, doi:10.3762/bjnano.9.10

• from the precursor is not a relevant reaction in the electron-induced degradation of MeCpPtMe3 layers. In addition, the m/z 39 trace gives evidence that ESD of the precursor is negligible. According to previous gas phase experiments [21], the dominant fragmentation proceeding via dissociative electron

• attachment (DEA) leads to loss of only one neutral CH3 ligand. DEA occurs at low electron energies characteristic of the secondary electrons that are released in large numbers under impact of a high energy primary electron beam and are therefore thought to make major contributions to deposit formation

Response under low-energy electron irradiation of a thin film of a potential copper precursor for focused electron beam induced deposition (FEBID)

• Leo Sala,
• Iwona B. Szymańska,
• Céline Dablemont,
• Anne Lafosse and
• Lionel Amiaud

Beilstein J. Nanotechnol. 2018, 9, 57–65, doi:10.3762/bjnano.9.8

• process is dissociative electron attachment (DEA), which produces neutral species and an anion that can be neutralized. ESD efficiency is higher at high energy because DI is the most efficient process. However, in FEBID experiments, the distribution of secondary electrons strongly peaks in the range of 1

• , which is low compared to the electronic excitation energy and ionisation energy of primary amines (respectively, 5.9 eV and 8.8 eV [21][22]) points out possible resonances of dissociative electron attachment processes leading to fragmentation of neutral ethylamine. The nature of the resonance is

• difficult to determine from the data. To our knowledge, no measurement of amine metal cation complex dissociation is described in literature for comparison, and the resonances for dissociative electron attachment in amine compounds, known from gas-phase studies [23][24][25][26], are expected to be shifted

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

• is to develop dedicated FEBIP precursors [24]. The high-energy electrons in the focused beam (typically 1–15 keV) induce reactions through ionization processes, such as dissociative electron attachment and dissociative ionization [6][25][26]. While ionization reactions can be very selective [27

Synthesis of [{AgO₂CCH₂OMe(PPh₃)}_n] and theoretical study of its use in focused electron beam induced deposition

• Jelena Tamuliene,
• Julian Noll,
• Peter Frenzel,
• Tobias Rüffer,
• Alexander Jakob,
• Bernhard Walfort and
• Heinrich Lang

Beilstein J. Nanotechnol. 2017, 8, 2615–2624, doi:10.3762/bjnano.8.262

• ≈50. The reactions of a dissociative ionization, dipolar dissociation, dissociative electron attachment etc. were studied to obtain the reaction pathways energetically most likely and relate to experimentally obtained species. It implies that the energetic of reactions leading from the intact neutral

Interactions of low-energy electrons with the FEBID precursor chromium hexacarbonyl (Cr(CO)₆)

• Jusuf M. Khreis,
• João Ameixa,
• Filipe Ferreira da Silva and
• Stephan Denifl

Beilstein J. Nanotechnol. 2017, 8, 2583–2590, doi:10.3762/bjnano.8.258

• spectrometer with reverse geometry. Dissociative electron attachment leads to the formation of a series of anions by the loss of CO ligand units. The bare chromium anion is formed by electron capture at an electron energy of about 9 eV. Metastable decays of Cr(CO)5− into Cr(CO)4−, Cr(CO)4− into Cr(CO)3− and Cr

• ; dissociative electron attachment; electron ionization; FEBID; metastable decay; Introduction Organometallic compounds have been extensively studied since they are used for a broad field of applications. Among the variety of applications, nanotechnologies have caught special attention since organometallic

• backscattered electrons with the precursor molecules. LEE initiate chemical reactions on the surface by dissociative electron attachment (DEA) and dissociative electron ionization, as well as neutral dissociation. Those processes need to be well understood, in order to maximise the quality of deposited metal as

Amplified cross-linking efficiency of self-assembled monolayers through targeted dissociative electron attachment for the production of carbon nanomembranes

• Sascha Koch,
• Christopher D. Kaiser,
• Paul Penner,
• Michael Barclay,
• Lena Frommeyer,
• Daniel Emmrich,
• Patrick Stohmann,
• Tarek Abu-Husein,
• Andreas Terfort,
• D. Howard Fairbrother,
• Oddur Ingólfsson and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2017, 8, 2562–2571, doi:10.3762/bjnano.8.256

• 10.3762/bjnano.8.256 Abstract The determination of the negative ion yield of 2′-chloro-1,1′-biphenyl (2-Cl-BP), 2′-bromo-1,1′-biphenyl (2-Br-BP) and 2′-iodo-1,1′-biphenyl (2-I-BP) upon dissociative electron attachment (DEA) at an electron energy of 0 eV revealed cross section values that were more than

• nanomembrane; dissociative electron attachment; dissociative ionization; helium ion microscopy; self-assembled monolayers; X-ray photoelectron spectroscopy; Introduction Carbon nanomembranes (CNMs) are two-dimensional molecular sheets with a thickness of one to a few nanometers, high mechanical strength, and

• ]. In the energy range from about 0–100 eV, electron-induced bond rupture may proceed through four distinctly different initiating processes: dissociative ionization (DI), neutral or dipolar dissociation upon electronic excitation (ND and DD, respectively) or through dissociative electron attachment

Electron beam induced deposition of silacyclohexane and dichlorosilacyclohexane: the role of dissociative ionization and dissociative electron attachment in the deposition process

• Ragesh Kumar T P,
• Sangeetha Hari,
• Krishna K Damodaran,
• Oddur Ingólfsson and
• Cornelis W. Hagen

Beilstein J. Nanotechnol. 2017, 8, 2376–2388, doi:10.3762/bjnano.8.237

• dissociative electron attachment, SCH is inert with respect to this process. We discuss our deposition experiments in context of the efficiency of these different electron-induced fragmentation processes. With regards to the deposition dynamics, we observe a substantially faster growth from DCSCH and a higher

• features: a maximum well below 10 eV with still a significant contribution close to 0 eV and a high-energy tail extending well above 100 eV [3][5][12]. In this energy range electron induced molecular fragmentation may proceed through four different processes: dissociative electron attachment (DEA; Equation

• stoichiometry. The oxygen content in the DCSCH deposits is about double that of the SCH deposits. Only marginal chlorine is observed in the deposits of from DCSCH. We discuss these observations in context of potential approaches for Si deposition. Keywords: dichlorosilacyclohexane; dissociative electron

Dissociative electron attachment to coordination complexes of chromium: chromium(0) hexacarbonyl and benzene-chromium(0) tricarbonyl

• Janina Kopyra,
• Paulina Maciejewska and
• Jelena Maljković

Beilstein J. Nanotechnol. 2017, 8, 2257–2263, doi:10.3762/bjnano.8.225

• we report the results of dissociative electron attachment (DEA) to gas-phase chromium(0) hexacarbonyl (Cr(CO)6) and benzene-chromium(0) tricarbonyl ((η6-C6H6)Cr(CO)3) in the energy range of 0–12 eV. Measurements have been performed utilizing an electron-molecular crossed beam setup. It was found that

• ; dissociative electron attachment; gas phase reactions; mass spectrometry; Introduction Organometallic compounds are a large class of compounds with numerous applications such as homogeneous catalysts for the synthesis of fine chemicals or even enantiomerically pure products used in the pharmaceutical industry

• molecules via various decomposition processes such as dissociative ionization (DI), dipolar dissociation (DD), neutral dissociation (ND), and dissociative electron attachment (DEA) [8]. These reactions occur with relatively high cross sections and typically result in partial fragmentation of the precursor

Comprehensive investigation of the electronic excitation of W(CO)₆ by photoabsorption and theoretical analysis in the energy region from 3.9 to 10.8 eV

• Mónica Mendes,
• Khrystyna Regeta,
• Filipe Ferreira da Silva,
• Nykola C. Jones,
• Søren Vrønning Hoffmann,
• Gustavo García,
• Chantal Daniel and
• Paulo Limão-Vieira

Beilstein J. Nanotechnol. 2017, 8, 2208–2218, doi:10.3762/bjnano.8.220

• beam impinging on the surface where dissociative electron attachment (DEA) processes are relevant, although at those energies electron impact excitations yielding neutral dissociation are prevalent in detriment to DEA [25]. Gas-phase DEA studies in the electron energy range from 0 to 14 eV reported by

Suppression of low-energy dissociative electron attachment in Fe(CO)₅ upon clustering

• Jozef Lengyel,
• Peter Papp,
• Štefan Matejčík,
• Jaroslav Kočišek,
• Michal Fárník and
• Juraj Fedor

Beilstein J. Nanotechnol. 2017, 8, 2200–2207, doi:10.3762/bjnano.8.219

• the most attention in recent years (i.e., dissociative electron attachment at energies close to 0 eV) becomes suppressed upon increasing aggregation of iron pentacarbonyl. We attribute this suppression to the electrostatic shielding of a long-range interaction that strongly enhances the dissociative

• electron attachment in isolated Fe(CO)5. Keywords: aggregation effects; dissociative electron attachment; FEBID; iron pentacarbonyl; long-range interactions; Introduction In recent years a number of gas-phase studies on molecules that are commonly used as precursors in electron-induced nanofabrication

• have stressed the importance of electrons with energy below 1 eV [1][2][3]. In many cases, these cause the cleavage of one metal–ligand bond via dissociative electron attachment (DEA) and corresponding cross sections reach unusually high values [2][3]. Iron pentacarbonyl, Fe(CO)5, is no exception: the

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

• resultant grain structure and carbon removal. In standard EBID using the MeCpPt(IV)Me3 precursor, the initial reaction leading to condensation occurs with the cleavage of a single bond between a methyl group and the platinum atom, surmised to occur primarily through dissociative electron attachment (DEA

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

• formation of CO2 and CO. Both compounds have also been observed before as products of the electron-induced fragmentation of carboxylic acids with CO2 being dominant [43]. The reaction proceeds via both, dissociative electron attachment at electron energies around 1 eV, which are typical for secondary

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

• FEBID, specifically, dissociative electron attachment, dissociative ionization, neutral dissociation, and dipolar dissociation, emphasizing the different nature and energy dependence of each process. We then explore the value of studying these processes through comparative gas phase and surface studies

• are needed, these studies are an important stepping-stone toward better understanding the fundamental physics behind the deposition process and establishing design criteria for optimized FEBID precursors. Keywords: dipolar dissociation; dissociative electron attachment; dissociative ionization

• impinging on a Ni(111) surface [6] and for 1 keV electrons impinging on a Ag(100) surface [9], along with the approximate electron energy ranges in which the principal electron induced processes are operative, i.e., dissociative electron attachment (DEA), neutral dissociation (ND), and dissociative