Impact of contact resistance on the electrical properties of MoS₂ transistors at practical operating temperatures

• Filippo Giannazzo,
• Gabriele Fisichella,
• Aurora Piazza,
• Salvatore Di Franco,
• Giuseppe Greco,
• Simonpietro Agnello and
• Fabrizio Roccaforte

Beilstein J. Nanotechnol. 2017, 8, 254–263, doi:10.3762/bjnano.8.28

• Back-gated transistors were fabricated using MoS2 flakes exfoliated from molybdenite bulk crystals (supplier SPI [19]) with thicknesses ranging from ≈40 to ≈50 nm and transferred onto a highly doped n-type Si substrate covered with 380 nm of thermally grown SiO2. An accurate sample preparation protocol

• from 298 to 373 K was determined and the physical mechanisms of these dependences were discussed. Results and Discussion Back-gated transistors have been fabricated using multilayer MoS2 flakes (with thickness ranging from ≈40 to ≈50 nm) exfoliated from bulk molybdenite crystals onto a highly doped Si

• substrate covered with 380 nm thick, thermally grown SiO2. Such relatively thick MoS2 samples have been chosen since it has been reported that the electrical properties (μ, Vth) of simple back-gated transistors fabricated with multilayer MoS2 are much less affected by the effect of the external environment

Colorimetric gas detection by the varying thickness of a thin film of ultrasmall PTSA-coated TiO₂ nanoparticles on a Si substrate

• Urmas Joost,
• Andris Šutka,
• Meeri Visnapuu,
• Aile Tamm,
• Meeri Lembinen,
• Mikk Antsov,
• Kathriin Utt,
• Krisjanis Smits,
• Ergo Nõmmiste and
• Vambola Kisand

Beilstein J. Nanotechnol. 2017, 8, 229–236, doi:10.3762/bjnano.8.25

• ultrasmall TiO2 nanoparticles (NPs) for a colorimetric gas sensor. The functional thin film is extremely simple, consisting of TiO2 NPs and the elastic binding agent p-toluenesulfonic acid (PTSA) on a Si substrate. It is not necessary to use particles with narrow size distributions of diameters in well

• from the film/substrate interface, as schematically demonstrated in Figure 2. The functional thin film is extremely simple, consisting of TiO2 NPs (the mean size of 3 nm was measured by TEM and DLS, Figure 3a and Figure 3e) and the binding agent PTSA on a Si substrate. It is a colorimetric gas sensor

Influence of hydrofluoric acid treatment on electroless deposition of Au clusters

• Rachela G. Milazzo,
• Antonio M. Mio,
• Giuseppe D’Arrigo,
• Emanuele Smecca,
• Alessandra Alberti,
• Gabriele Fisichella,
• Filippo Giannazzo,
• Corrado Spinella and
• Emanuele Rimini

Beilstein J. Nanotechnol. 2017, 8, 183–189, doi:10.3762/bjnano.8.19

• uniformly assemble on the Si substrate with elongated and wide structures of a few tens of nanometers long. After 4 min in DHF (Figure 2b), they arrange as small particles of spherical shape with a radius of less than 10 nm. Although the images were taken in bright field mode, a huge mass contrast between

• , showed the presence of randomly oriented Au clusters coexisting with the heteroepitaxial regions on the Si substrate. Moreover, the shape of the (200) diffraction peak indicates that two families of grains, both exhibiting texturing in the [001] crystallographic direction, are present. The deconvolution

• TEM micrographs of AuNPs electroless deposited on a Si substrate by immersion for 3 s in the solution after a DHF pretreatment of 240 s; sample preparation (a) standard high energy and (b) gentle milling procedure. Gold electroless deposition on Si(100) after an DHF pretreatment of 10 s (a) and 240 s

Nitrogen-doped twisted graphene grown on copper by atmospheric pressure CVD from a decane precursor

• Ivan V. Komissarov,
• Nikolai G. Kovalchuk,
• Vladimir A. Labunov,
• Ksenia V. Girel,
• Olga V. Korolik,
• Mikhail S. Tivanov,
• Algirdas Lazauskas,
• Mindaugas Andrulevičius,
• Tomas Tamulevičius,
• Viktoras Grigaliūnas,
• Šarunas Meškinis,
• Sigitas Tamulevičius and
• Serghej L. Prischepa

Beilstein J. Nanotechnol. 2017, 8, 145–158, doi:10.3762/bjnano.8.15

• the insets to Figures Figure 2a and Figure 2b the 2D peaks are shown revealing the symmetry of the 2D band. The latter indicates the weak interlayer interaction, which will be discussed later. In Figure 3a we demonstrate the Rayleigh image of sample A transferred to a SiO2/Si substrate. Raman mapping

• 1588 cm−1 against 1580 cm−1 for SLG [25]. Figure 5a–d shows Raman maps (400 points) of sample B transferred onto a SiO2/Si substrate. The corresponding histograms are presented in Figure 6a–d. A single Raman spectrum was accumulated for 10 s with a laser wavelength of 473 nm and a beam diameter of

• partitioning procedure following different parameters (this result is not shown here). The obtained results are in reasonable agreement with each other. Therefore, in order to demonstrate the universality of the elaborated method, for sample B on a SiO2/Si substrate, the Raman data set splitting was based on

Ordering of Zn-centered porphyrin and phthalocyanine on TiO₂(011): STM studies

• Piotr Olszowski,
• Lukasz Zajac,
• Szymon Godlewski,
• Bartosz Such,
• Rémy Pawlak,
• Antoine Hinaut,
• Res Jöhr,
• Thilo Glatzel,
• Ernst Meyer and
• Marek Szymonski

Beilstein J. Nanotechnol. 2017, 8, 99–107, doi:10.3762/bjnano.8.11

• role, the mechanism involved in such an interaction was concerned with the specific p–d orbital coupling between the localized Si substrate pz states on the B-passivated Si(111) surface and the metal atom at the center of the flat laying phthalocyanine molecule. This type of mechanism is not applicable

Sub-nanosecond light-pulse generation with waveguide-coupled carbon nanotube transducers

• Felix Pyatkov,
• Svetlana Khasminskaya,
• Vadim Kovalyuk,
• Frank Hennrich,
• Manfred M. Kappes,
• Gregory N. Goltsman,
• Wolfram H. P. Pernice and
• Ralph Krupke

Beilstein J. Nanotechnol. 2017, 8, 38–44, doi:10.3762/bjnano.8.5

• electron beam lithography on top of Si3N4/SiO2/Si substrate. Au/Cr contacts were produced by physical vapor deposition, and 600 nm wide, half-etched Si3N4-waveguides were formed with reactive ion etching. A typical sample contains tens of contact pairs and CNTs that were placed in between using

Annealing-induced recovery of indents in thin Au(Fe) bilayer films

• Anna Kosinova,
• Ruth Schwaiger,
• Leonid Klinger and
• Eugen Rabkin

Beilstein J. Nanotechnol. 2016, 7, 2088–2099, doi:10.3762/bjnano.7.199

• temperature range of 250–450 °C [3]. It should be noted that in all three works [1][2][3] the maximum indentation depth was larger than the metal film thickness, which resulted in significant modification of the Si substrate. Still, the microscopic mechanisms responsible for redistribution of matter in the

Cubic chemically ordered FeRh and FeCo nanomagnets prepared by mass-selected low-energy cluster-beam deposition: a comparative study

• Veronique Dupuis,
• Anthony Robert,
• Arnaud Hillion,
• Ghassan Khadra,
• Nils Blanc,
• Damien Le Roy,
• Florent Tournus,
• Clement Albin,
• Olivier Boisron and
• Alexandre Tamion

Beilstein J. Nanotechnol. 2016, 7, 1850–1860, doi:10.3762/bjnano.7.177

• between low signal from the Si substrate and maximum intensity of the Bragg (110) peak. The Figure 7 shows the measured X-ray scattering where we can see three peaks which correspond to the main Bragg peaks common to the B2 and bcc structures. These three peaks, showing the very good crystallinity of the

Localized surface plasmons in structures with linear Au nanoantennas on a SiO₂/Si surface

• Ilya A. Milekhin,
• Sergei A. Kuznetsov,
• Ekaterina E. Rodyakina,
• Alexander G. Milekhin,
• Alexander V. Latyshev and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2016, 7, 1519–1526, doi:10.3762/bjnano.7.145

• coupling also depends on the dielectric function of a surrounding medium that makes the LSPR energy different for nanoantennas backed by a bare Si substrate and when a SiO2 sublayer is introduced beneath the nanoantennas. Figure 4 illustrates the relation between the LSPR frequency and the SiO2 layer

• thickness derived from the IR spectra of nanoantennas with the underlying SiO2 layer created on top of the Si substrate. It can be seen from Figure 4 that the LSPR frequency of the nanoantennas fabricated on a thick SiO2 layer is blue-shifted by about 1000 cm−1 with respect to the structures on bare Si due

• 1900 nm (a,b) and 1400 nm (c,d) fabricated on SiO2 layers of different thicknesses measured at normal incidence. The IR transmission spectrum of a 49 nm thick SiO2 layer on a Si substrate measured at off-normal (70°) incidence is shown for comparison. The vertical dashed lines indicate the frequency

Nanostructured germanium deposited on heated substrates with enhanced photoelectric properties

• Ionel Stavarache,
• Valentin Adrian Maraloiu,
• Petronela Prepelita and
• Gheorghe Iordache

Beilstein J. Nanotechnol. 2016, 7, 1492–1500, doi:10.3762/bjnano.7.142

• the n-Si substrate was grounded. In this configuration, the bias voltage is applied across the series combination of junctions, namely at the ITO/Ge:SiO2 interface, the Ge:SiO2 film region, and the junction situated at Ge:SiO2/Si interface [34]. The rectifying behavior (102 rectification ratio at 1 V

• as a result of the separation of electron–hole pairs generated in the Ge-nps and the Si substrate. The obtained photoresponse gain factor increases from about 102 (at 300 °C) to about 103 (at 500 °C) with the temperature increase during deposition. Under illumination, electrons and holes are

• generated in the Ge-nps and in the Si substrate and they move by tunneling between neighboring Ge-nps. During transport, the positively charged holes are dynamically trapped within the Ge-nps incorporated into SiO2 matrix improving the electron injection, leading to an increase of negative photoconductivity

NO gas sensing at room temperature using single titanium oxide nanodot sensors created by atomic force microscopy nanolithography

• Li-Yang Hong and
• Heh-Nan Lin

Beilstein J. Nanotechnol. 2016, 7, 1044–1051, doi:10.3762/bjnano.7.97

• nanolithography [30][32] procedure is shown in Figure 1. A 40 nm thick poly(methylmethacrylate) (PMMA) film was spin-coated on a Si substrate that had a thick oxide layer. By using an AFM (Smena, NT-MDT, Russia), a straight nanogroove was generated in the PMMA film. A Ti film was deposited by electron-beam

Magnetic switching of nanoscale antidot lattices

• Ulf Wiedwald,
• Joachim Gräfe,
• Kristof M. Lebecki,
• Maxim Skripnik,
• Felix Haering,
• Gisela Schütz,
• Paul Ziemann,
• Eberhard Goering and
• Ulrich Nowak

Beilstein J. Nanotechnol. 2016, 7, 733–750, doi:10.3762/bjnano.7.65

Correlative infrared nanospectroscopic and nanomechanical imaging of block copolymer microdomains

• Benjamin Pollard and
• Markus B. Raschke

Beilstein J. Nanotechnol. 2016, 7, 605–612, doi:10.3762/bjnano.7.53

• interface, as PMMA is more polar than PS and tends toward the polar SiO2 native oxide layer of the Si substrate [17]. Models suggest that this PS surface layer is roughly half the microdomain size when in equilibrium [18], though we can expect nonuniformity and local variations of the surface layer in this

Orientation of FePt nanoparticles on top of a-SiO₂/Si(001), MgO(001) and sapphire(0001): effect of thermal treatments and influence of substrate and particle size

• Martin Schilling,
• Paul Ziemann,
• Zaoli Zhang,
• Johannes Biskupek,
• Ute Kaiser and
• Ulf Wiedwald

Beilstein J. Nanotechnol. 2016, 7, 591–604, doi:10.3762/bjnano.7.52

• Figure 2a the RHEED pattern for a 3 nm Fe48Pt52 film on a SiO2/Si substrate is presented after post annealing at 650 °C for 30 min. A diffuse intensity distribution is observed without any superposed streaks or spots. The bright ring around the direct beam is a halo feature due to the RHEED arrangement

Characterisation of thin films of graphene–surfactant composites produced through a novel semi-automated method

• Nik J. Walch,
• Alexei Nabok,
• Frank Davis and
• Séamus P. J. Higson

Beilstein J. Nanotechnol. 2016, 7, 209–219, doi:10.3762/bjnano.7.19

• index (n) and extinction coefficient (k) of graphene films can be found by fitting the above spectra to the model using the dedicated software by J. A. Woollam. In this particular case, the model of the reflecting system consists of the following three layers: (1) Si substrate; (2) the layer of native

• of data in Figure 9a, the fitting for the thickness of the native SiO2 layer was performed first using the data for the bare Si substrate. The thickness of SiO2 layer obtained (d = 3.2 nm) was then fixed for consecutive fittings. The PAH/graphene(−)SDS film was considered as one layer in the

Synthesis and applications of carbon nanomaterials for energy generation and storage

• Marco Notarianni,
• Jinzhang Liu,
• Kristy Vernon and
• Nunzio Motta

Beilstein J. Nanotechnol. 2016, 7, 149–196, doi:10.3762/bjnano.7.17

Chemical bath deposition of textured and compact zinc oxide thin films on vinyl-terminated polystyrene brushes

• Nina J. Blumenstein,
• Caroline G. Hofmeister,
• Peter Lindemann,
• Cheng Huang,
• Johannes Baier,
• Andreas Leineweber,
• Stefan Walheim,
• Christof Wöll,
• Thomas Schimmel and
• Joachim Bill

Beilstein J. Nanotechnol. 2016, 7, 102–110, doi:10.3762/bjnano.7.12

• ), (002), (101), (102) and (110) reflections of hexagonal ZnO are visible in the XRD patterns (cf. JCPDS no. 01-079-0206). For the PS brush sample (Figure 4b), a pronounced preferred orientation of the ZnO crystallites with the hexagonal c-axis perpendicular to the plane of the Si substrate is indicated

Surface-enhanced Raman scattering by colloidal CdSe nanocrystal submonolayers fabricated by the Langmuir–Blodgett technique

• Alexander G. Milekhin,
• Larisa L. Sveshnikova,
• Tatyana A. Duda,
• Ekaterina E. Rodyakina,
• Volodymyr M. Dzhagan,
• Ovidiu D. Gordan,
• Sergey L. Veber,
• Cameliu Himcinschi,
• Alexander V. Latyshev and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2015, 6, 2388–2395, doi:10.3762/bjnano.6.245

• ]. The fabrication details of regular arrays of Au nanoclusters and dimers on a Si substrate are presented in [29]. In addition to regular arrays of Au nanoclusters, arrays of paired Au nanoclusters or dimers were fabricated by electron beam lithography on a Si substrate covered with 75 nm of SiO2. The

• regular arrays of Au nanoclusters Typical SEM and HR-TEM images of a single monolayer of CdSe NCs deposited by the LB technique on the plasmonic substrate and on a carbon-coated Cu grid are shown in Figure 2. This demonstrates a dense, homogeneous coverage of the NCs for both the Si substrate with a Au

• nanocluster array and the Cu grid. The Raman spectrum acquired from the area where CdSe NCs are deposited on the Si substrate reveals only features inherent to crystalline Si. However, the Raman spectra of CdSe NCs deposited on the nanocluster arrays (Figure 3a) reveal a pronounced peak at about 207.5 cm−1

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

• conventionally or with a laser the flat morphology of square, line, or tip deposits on the pre-patterned SiO2/Si substrate changes (Figure 3 and Figure 4). While the laser allows for local heating, the conventional hotplate approach allows for more accurate temperature measurements. The visible onset of Cu

• nanocrystal precipitation on the deposit surface starts at around 150 °C for the Cu(hfac)2 deposits on the pre-patterned SiO2/Si substrate. Further heating to about 200 °C for 30 min did not visibly change the appearance of the Cu nanocrystal precipitation. EDX analysis after conventional heating to 200 °C

Magnetic properties of iron cluster/chromium matrix nanocomposites

• Arne Fischer,
• Robert Kruk,
• Di Wang and
• Horst Hahn

Beilstein J. Nanotechnol. 2015, 6, 1158–1163, doi:10.3762/bjnano.6.117

• mbar range during the deposition. Fex/Cr samples consist of the already mentioned Si substrate with a native oxide layer, a 10 nm Cr base layer, the Fe cluster/Cr matrix layer, a 10 nm Cr top layer and a 10 nm Au film as oxidation protection. This geometry makes sure that the Fe clusters are in contact

• interactions) become dominant. Hysteresis loops were recorded at 5 K after field cooling from 350 K, which is above the TN of Cr (311 K [16]), in an external magnetic field of μ0H = 4.5 T. A linear diamagnetic background originating from the Si substrate as well as the Au layers was subtracted. The coercivity

Fulleropeptide esters as potential self-assembled antioxidants

• Mira S. Bjelaković,
• Tatjana J. Kop,
• Jelena Đorđević and
• Dragana R. Milić

Beilstein J. Nanotechnol. 2015, 6, 1065–1071, doi:10.3762/bjnano.6.107

• mM) on a Si substrate at room temperature. The ester 1 arranged into a flower-shaped, hierarchically ordered architecture of curled leaf-like particles with diameters of up to 5 μm (Figure 3A) [25]. Figure 3B–F shows selected representative examples of SEM micrographs of typical fulleropeptide self

• compound was dispersed on a brass substrate. The dried samples obtained from dilute solutions were prepared as follows: 10 μL of 1 mM solution in the PhMe/MeOH (5:1, v/v) mixture of fullerene derivatives was deposited on the surface of a Si substrate (10 × 10 mm) and left overnight to slowly evaporate in a

• particles of 4 and 11. (E, F) Networks of spherical particles of 9 and 12, all prepared from 5:1 PhMe/MeOH (v/v) on a Si substrate after evaporation of a 1 mM solution. Scale bars correspond to 5 μm. Representatives of the SEM images of the self-organized rods of Fp–GABA ester 1 (A) and fulleropeptides self

Fabrication of high-resolution nanostructures of complex geometry by the single-spot nanolithography method

• Alexander Samardak,
• Margarita Anisimova,
• Aleksei Samardak and
• Alexey Ognev

Beilstein J. Nanotechnol. 2015, 6, 976–986, doi:10.3762/bjnano.6.101

• outer edges vary significantly. In the case of a monocrystalline Si substrate, the ring has a sharp edge with a small resist undercut (Figure 1a). As seen in Figure 1b, exposure of the resist on the polycrystalline Au film leads to a deep undercut and rough edges after development. The physics behind

• emission is very broad and corresponds to the normalized energy, W = E/E0 = 0.5, where E and E0 are the energy of backscattered and primary electrons, respectively. For Au, W = 0.95–0.98. As a result, in the case of the Au substrate, the rings have a much smaller outer diameter compared to the Si substrate

• (Figure 3). Even at a dose of 2.5 pC, the ring on the Au substrate is still smaller than that patterned onto the Si substrate at a dose 0.35 pC. Our experimental findings are supported by Monte Carlo simulations performed with NanoPECS software [17]. In the case of the Si substrate, most of the electrons

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

• pre-cleaned 100 nm thermal SiO2 on Si substrate and then purified. The deposition and subsequent purification was performed using a FEI NOVA 600 dual-beam system equipped with FEI and Omniprobe gas injection systems. Prior to deposition, the substrate was sonicated in isopropanol for 5 min and

Combination of surface- and interference-enhanced Raman scattering by CuS nanocrystals on nanopatterned Au structures

• Alexander G. Milekhin,
• Nikolay A. Yeryukov,
• Larisa L. Sveshnikova,
• Tatyana A. Duda,
• Ekaterina E. Rodyakina,
• Victor A. Gridchin,
• Evgeniya S. Sheremet and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2015, 6, 749–754, doi:10.3762/bjnano.6.77

• SEM image of the edge of a periodic Au nanocluster array on a Si substrate with deposited CuS NCs is presented in Figure 4a. One can see that the CuS NCs are homogeneously distributed on the Au nanocluster array and on the bare Si surface with an average thickness of about 1 ML. The Raman spectrum

• measured from the area where CuS NCs are formed on bare Si (lower part in Figure 4a) shows only one strong Raman line at 521 cm−1 related to the Si substrate (lower curve in Figure 4b). Weak Raman features located in the spectral range of 400–500 cm−1 are also typical for monocrystalline Si [21] while no

• , CuS NCs were deposited on arrays of Au nanoclusters fabricated using nanolithography on a 75 nm thick SiO2 layer. Obviously, the LSPR energy of the Au nanocluster arrays fabricated on a SiO2 layer and on a Si substrate can be different due to the difference of dielectric functions of SiO2 and Si [22

Morphological and structural characterization of single-crystal ZnO nanorod arrays on flexible and non-flexible substrates

• Omar F. Farhat,
• Mohd M. Halim,
• Mat J. Abdullah,
• Mohammed K. M. Ali and
• Nageh K. Allam

Beilstein J. Nanotechnol. 2015, 6, 720–725, doi:10.3762/bjnano.6.73

• work [17], the lattice and thermal mismatches between ZnO and a Si substrate are 15 and 60%, respectively. PET and glass substrates are amorphous, and are thus expected to result in even larger lattice and thermal mismatching with ZnO than for the Si substrate [18]. In the current study, the lattice

• -induced scattering [22]. Also, other highly intense peaks were detected in sample (b) in the region 600–890 cm−1 characteristic of the PET substrate (sub), which also can be seen in sample (a) for glass substrate (sub), yet it was not detected for the Si substrate. Conclusion Single-crystal ZnO nanorod