Observation of a photoinduced, resonant tunneling effect in a carbon nanotube–silicon heterojunction

• Carla Aramo,
• Antonio Ambrosio,
• Michelangelo Ambrosio,
• Maurizio Boscardin,
• Paola Castrucci,
• Michele Crivellari,
• Marco Cilmo,
• Maurizio De Crescenzi,
• Francesco De Nicola,
• Emanuele Fiandrini,
• Valentina Grossi,
• Pasqualino Maddalena,
• Maurizio Passacantando,
• Sandro Santucci,
• Manuela Scarselli and
• Antonio Valentini

Beilstein J. Nanotechnol. 2015, 6, 704–710, doi:10.3762/bjnano.6.71

• obtained by growing a continuous layer of multiwall carbon nanotubes on an n-doped silicon substrate. The multiwall carbon nanostructures were grown by a chemical vapor deposition (CVD) technique on a 60 nm thick, silicon nitride layer, deposited on an n-type Si substrate. The heterojunction

• . Conclusion In this paper, we report the results of a negative differential resistance behavior generated by the incident radiation, which varies as a function of wavelength and incident power intensity for a new photosensitive device consisting of MWCNTs grown at 700 °C on a Si substrate. The junction

• still under investigation, suggest the potential use of the device for optoelectronics applications. (a) Schematic front view and (b) side view of the Si substrate produced by Fondazione Bruno Kessler (FBK) in Povo, Trento (Italy). (a) Scanning electron microscopy (SEM) image of MWCNT samples grown on

Simple approach for the fabrication of PEDOT-coated Si nanowires

• Mingxuan Zhu,
• Marielle Eyraud,
• Judikael Le Rouzo,
• Nadia Ait Ahmed,
• Florence Boulc’h,
• Claude Alfonso,
• Philippe Knauth and
• François Flory

Beilstein J. Nanotechnol. 2015, 6, 640–650, doi:10.3762/bjnano.6.65

• transmission electron microcopies, energy-dispersive X-ray analysis, and IR spectroscopy. Results and Discussion Effect of tapering on SiNW antireflection The SiNWs, as prepared from an n-type Si substrate according to the process described in the Experimental section, can be seen in Figure 1. The geometry of

• . The chosen experimental conditions resulted in a dense array of smooth Si nanowires, 2 µm in length, approximately 100 nm thick, and oriented perpendicular to the Si substrate. In this case, the space between the wires was quite small. TEM observation of the nanowires allows the dimensions to be

• -type Si substrate conductive in the anodic area. The deposition was controlled by a Solartron SI 1287 with a computer running CorrWare software. A non-aqueous medium was preferred over the classical sodium polystyrene sulfonate (NaPSS) aqueous environment in order to avoid the important silicon

Entropy effects in the collective dynamic behavior of alkyl monolayers tethered to Si(111)

• Christian Godet

Beilstein J. Nanotechnol. 2015, 6, 583–594, doi:10.3762/bjnano.6.60

• thickness (spectroscopic ellipsometry, SE), molecular packing density and possible interface oxidation of the Si substrate (X-ray photoelectron spectroscopy). The surface density of acid groups (0.4 × 1014 cm−2) and the total organic layer (acid + alkyl) coverage (2.6 × 1014 cm−2) were obtained by XPS using

Electrical properties of single CdTe nanowires

• Elena Matei,
• Camelia Florica,
• Andreea Costas,
• María Eugenia Toimil-Molares and
• Ionut Enculescu

Beilstein J. Nanotechnol. 2015, 6, 444–450, doi:10.3762/bjnano.6.45

• transport through the nanowire, a third electrical contact was made to the n++ Si substrate. A comparison of the transport properties of the nanowires with and without a passivated thin layer of PMMA was performed. This polymer passivation layer was deposited onto the wire by means of spin coating. SEM

Boosting the local anodic oxidation of silicon through carbon nanofiber atomic force microscopy probes

• Gemma Rius,
• Matteo Lorenzoni,
• Soichiro Matsui,
• Masaki Tanemura and
• Francesc Perez-Murano

Beilstein J. Nanotechnol. 2015, 6, 215–222, doi:10.3762/bjnano.6.20

• relatively stiff cantilevers as specified above. The routines and conditions to perform LAO-AFM in the dynamic mode have been described in [1][19]. In brief, a target location onto the Si substrate is inspected for surface cleanliness. Then, the cantilever free oscillation is set to a low amplitude value

Synthesis of boron nitride nanotubes and their applications

• Saban Kalay,
• Zehra Yilmaz,
• Ozlem Sen,
• Melis Emanet,
• Emine Kazanc and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2015, 6, 84–102, doi:10.3762/bjnano.6.9

• first successful synthesis of patterned BNNTs was performed by catalytic CVD [56]. To produce pure and vertically aligned BNNTs, a Si substrate was coated with Al2O3 of 30 nm thickness, then MgO, Ni, or Fe catalysts was deposited on the surface of the Al2O3 by pulsed laser deposition. This substrate was

• setup, (b) stretching of dense BNNTs from the sample surface, (c) high magnification SEM image of BNNTs, (d) SEM images of slightly compressed BNNTs on a Si substrate, and (e) cross-sectional view of vertically aligned BNNTs. Figure adapted with permission from [56], copyright 2010 American Chemical

Bright photoluminescence from ordered arrays of SiGe nanowires grown on Si(111)

• D. J. Lockwood,
• N. L. Rowell,
• A. Benkouider,
• A. Ronda,
• L. Favre and
• I. Berbezier

Beilstein J. Nanotechnol. 2014, 5, 2498–2504, doi:10.3762/bjnano.5.259

• to 25 K) with excitation at 405 and 458 nm. There are four major features in the energy range of interest (980–1120 meV) at energies of 1040.7, 1082.8, 1092.5, and 1098.5 meV, which are assigned to the NW-transverse optic (TO) Si–Si mode, NW-transverse acoustic (TA), Si–substrate–TO and NW-no-phonon

• -shell NWs using a condensation process that we have developed. Three NW samples were prepared for this study: Sample (A), where the NWs are grown randomly across the Si substrate; sample (B), where the nanowires decorate the edges of 400 × 400 µm2 boxes; and sample (C), where the NWs fill 400 × 400 µm2

• spectra obtained for sample (C) with excitation at 405 and 438 nm are compared in Figure 3. The two spectra exhibit the same features, most of which arise from the Si substrate together with a few arising from instrumental effects. The main difference between them, as also observed for the other two

Si/Ge intermixing during Ge Stranski–Krastanov growth

• Alain Portavoce,
• Khalid Hoummada,
• Antoine Ronda,
• Dominique Mangelinck and
• Isabelle Berbezier

Beilstein J. Nanotechnol. 2014, 5, 2374–2382, doi:10.3762/bjnano.5.246

• intermixing during Ge island formation, the Si cap or Si substrate/island interface is abrupt, exhibiting weak Si/Ge intermixing during Si deposition. The islands keep their usual {111} and {113} surface facets under the Si cap, and Ge segregation is observed only in {113} facets. The thickness and the Ge

• preparation, the second layer of islands (the WL and a small part of a surface island are recognizable), the Si buffer, the first layer of islands, and the Si substrate. APT analysis allows one-dimensional (1D) atomic composition profiles to be determined in any direction in the analyzed volume. Figure 4

• an average thickness ≈2.7 nm) and from 5 to 30 atom % Ge, respectively. Figure 5a shows a TEM cross-sectional view of a typical dome island exhibiting {111} and {113} facets forming an angle of 54.7° and 25.2°, respectively, with the (001) surface of the Si substrate [40]. Figure 5b,c presents only

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

• using solution-processed, p-type, ZnO nanoparticles and an n-type Si substrate. p-type ZnO nanoparticles were synthesized using a chemical synthesis route and characterized by XRD and a Hall effect measurement system. The device was fabricated by forming thin film of synthesized p-ZnO nanoparticles on

• an n-Si substrate using a dip coating technique. The device was then characterized by current–voltage (I–V) and capacitance–voltage (C–V) measurements. The effect of UV illumination on the I–V characteristics was also explored and indicated the formation of a highly rectifying, nano heterojunction

• nanoparticles were found to be +5 × 1014 cm−3, 31.63 cm2/Vs, and 395.19 Ωcm, respectively. These results clearly indicate that the synthesized ZnO nanoparticles have p-type conductivity. A Hall measurement of the n-Si substrate was also performed on a silicon wafer with dimensions 1.4 × 0.9 × 0.04 cm3. The

Properties of plasmonic arrays produced by pulsed-laser nanostructuring of thin Au films

• Katarzyna Grochowska,
• Katarzyna Siuzdak,
• Peter A. Atanasov,
• Carla Bittencourt,
• Anna Dikovska,
• Nikolay N. Nedyalkov and
• Gerard Śliwiński

Beilstein J. Nanotechnol. 2014, 5, 2102–2112, doi:10.3762/bjnano.5.219

• obtained the different velocities of the metallic (Au and Ta) film surfaces of 0.6 m/s and 1.9 m/s below and above the melting threshold, respectively [24]. Interestingly, the velocity values in the range of 20–70 m/s characteristic of the instability driven processes (i.e., film detachment from Si

• substrate, followed by dewetting and droplet formation) are in reasonable agreement with those observed in femtosecond experiments [25]. Similar to other laser-based methods, LNS results in a variety of unique properties not reproducible by other production routes. This contributes to new research on

Optical properties and electrical transport of thin films of terbium(III) bis(phthalocyanine) on cobalt

• Peter Robaschik,
• Pablo F. Siles,
• Daniel Bülz,
• Peter Richter,
• Manuel Monecke,
• Michael Fronk,
• Svetlana Klyatskaya,
• Daniel Grimm,
• Oliver G. Schmidt,
• Mario Ruben,
• Dietrich R. T. Zahn and
• Georgeta Salvan

Beilstein J. Nanotechnol. 2014, 5, 2070–2078, doi:10.3762/bjnano.5.215

• film acts as a back electrode. Samples for cs-AFM measurements were deposited on a Si substrate with a top SiO2 layer of 1 µm in order to eliminate possible leakage current. Figure 6b shows a 5 × 5 µm2 topography image of an 80 nm thick TbPc2 film which has the highest roughness, with respect to Figure

Towards bottom-up nanopatterning of Prussian blue analogues

• Virgile Trannoy,
• Marco Faustini,
• David Grosso,
• Sandra Mazerat,
• François Brisset,
• Alexandre Dazzi and
• Anne Bleuzen

Beilstein J. Nanotechnol. 2014, 5, 1933–1943, doi:10.3762/bjnano.5.204

• particles in the reaction media. Work is in progress in order to fully control this step. AFM images of a) the Si substrate b) Au10, c) Au20 and d) Au50. a) AFM and b) SEM images of the sample Au10NC. Depth distribution histogram in the c) dark and d) light areas. SEM micrographs of a) Au20NC and b) Au50NC

High speed e-beam lithography for gold nanoarray fabrication and use in nanotechnology

• Jorge Trasobares,
• François Vaurette,
• Marc François,
• Hans Romijn,
• Jean-Louis Codron,
• Dominique Vuillaume,
• Didier Théron and
• Nicolas Clément

Beilstein J. Nanotechnol. 2014, 5, 1918–1925, doi:10.3762/bjnano.5.202

• use an EBPG 5000 Plus from Vistec Lithography. The (100) Si substrate (resistivity = 10−3 Ω·cm) is cleaned with UV/ozone and native oxide etched before resist deposition. The e-beam lithography has been optimized by using a 45 nm-thick diluted (3:5 with anisole) PMMA (950 K). For the writing, we use

Synthesis of Pt nanoparticles and their burrowing into Si due to synergistic effects of ion beam energy losses

• Pravin Kumar,
• Udai Bhan Singh,
• Kedar Mal,
• Sunil Ojha,
• Indra Sulania,
• Dinakar Kanjilal,
• Dinesh Singh and
• Vidya Nand Singh

Beilstein J. Nanotechnol. 2014, 5, 1864–1872, doi:10.3762/bjnano.5.197

• substrate. The sharp feature just before Si substrate peak is a non-Bragg scattering peak. Conclusion We have reported the synthesis and the burrowing of Pt NPs due to medium-energy neon ion irradiation for Pt thin films deposited on a silicon substrate (Pt–Si). The ion fluence was kept constant (1017 ions

• polycrystalline in nature and (111) and (200) planes are clearly visible in the XRD pattern [47]. The reduced intensities and the broadening of the Pt peaks in the irradiated film confirm the Pt loss on the surface and the formation of NPs. The peak at around 2θ = 56º in the irradiated film is due to the Si

Silicon and germanium nanocrystals: properties and characterization

• Ivana Capan,
• Alexandra Carvalho and
• José Coutinho

Beilstein J. Nanotechnol. 2014, 5, 1787–1794, doi:10.3762/bjnano.5.189

• simple MOS structure, with Ge NCs embedded in the SiO2 film deposited on a Si substrate. In order to check for the existence of the deep level traps coming from the Si/SiO2 interface, temperature dependent C–V measurements have been performed. The activation energy of the electron emission has been

Growth and structural discrimination of cortical neurons on randomly oriented and vertically aligned dense carbon nanotube networks

• Christoph Nick,
• Sandeep Yadav,
• Ravi Joshi,
• Christiane Thielemann and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2014, 5, 1575–1579, doi:10.3762/bjnano.5.169

• structured on the silicon substrate. (d) The follow up growth of CNTs proceeds selectively on these spatially defined catalyst islands in a vertically aligned fashion on the Si substrate (left side), or in a randomly oriented fashion on an Au substrate (right side). SEM images of neurons cultured on randomly

Formation of Cu_xAu_1−x phases by cold homogenization of Au/Cu nanocrystalline thin films

• Alona Tynkova,
• Gabor L. Katona,
• Gabor A. Langer,
• Sergey I. Sidorenko,
• Svetlana M. Voloshko and
• Dezso L. Beke

Beilstein J. Nanotechnol. 2014, 5, 1491–1500, doi:10.3762/bjnano.5.162

• . Examples for the latter are the metallization of integrated circuits (the formation of a nanometric NiSi layer on the Si substrate [1][2]), or the production of thin chemically ordered FePt films for perpendicular magnetic data recording [3][4]. Regarding the basic understanding of such reactions the

• ), Au(25nm)/Cu(12nm), Au(10nm)/Cu(25nm) and Au(10nm)/Cu(15nm). During the deposition of metal layers the Si substrate was kept at room temperature and the Ar base pressure was set at 0.5 Pa. The rates of the deposition for Au and Cu layers were 0.85 nm/s and 0.5 nm/s, respectively. The samples were

Topology assisted self-organization of colloidal nanoparticles: application to 2D large-scale nanomastering

• Hind Kadiri,
• Serguei Kostcheev,
• Daniel Turover,
• Rafael Salas-Montiel,
• Komla Nomenyo,
• Anisha Gokarna and
• Gilles Lerondel

Beilstein J. Nanotechnol. 2014, 5, 1203–1209, doi:10.3762/bjnano.5.132

• scanning electron beam lithographic patterning of a 600 nm thick hydrogen silsesquioxane (HSQ) resist layer on a Si substrate. 20 patterns each with a size of 500 × 500 µm2 were fabricated on a Si substrate of 2 × 2 cm2. Si substrates were cleaned with acetone and then with a piranha solution for 24 h at

Nanoforging – Innovation in three-dimensional processing and shaping of nanoscaled structures

• Andreas Landefeld and
• Joachim Rösler

Beilstein J. Nanotechnol. 2014, 5, 1066–1070, doi:10.3762/bjnano.5.118

• axis [13]. The forging tools were machined by focused ion beam milling at the corner of a single crystalline Si-substrate. Varying tools in different positions were produced to allow several forging steps after each other (Figure 1). All of these tools are based on a spring principle similar to so

A nanometric cushion for enhancing scratch and wear resistance of hard films

• Katya Gotlib-Vainshtein,
• Olga Girshevitz,
• Chaim N. Sukenik,
• David Barlam and
• Sidney R. Cohen

Beilstein J. Nanotechnol. 2014, 5, 1005–1015, doi:10.3762/bjnano.5.114

• performs better than the titania on the Si substrate (Figure 4). These results suggest the beneficial influence of a softer substrate in improving the scratch resistance of the titania films. We refer to this as a “cushioning effect”. Taking the Young's modulus as a measure of the substrate compliance

• to 53% of that for the control Si substrate for the 8 nm titania on PDMS sample, and to 78% of the control for 36 nm of titania on PDMS. This compares favorably to the experimental results of Figure 10, where the friction coefficient for the 8 nm titania on PDMS is 46% that of the control, and for

• µN. Applied load vs friction force curves and µ evaluated by lateral force microscopy. FEA model for 7 nm titania layer for 10 nN force showing z-component of global stress distribution for a) PDMS substrate, and b) Si substrate. Inset shows the deformation, with z enlarged by 7× for PDMS and 70× for

Shape-selected nanocrystals for in situ spectro-electrochemistry studies on structurally well defined surfaces under controlled electrolyte transport: A combined in situ ATR-FTIR/online DEMS investigation of CO electrooxidation on Pt

• Sylvain Brimaud,
• Zenonas Jusys and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2014, 5, 735–746, doi:10.3762/bjnano.5.86

• structurally well characterized nanocrystals deposited on a Au film/Si substrate offer an attractive opportunity for performing spectro-electrochemical and in particular spectro–electrocatalytic measurements under enforced and well controlled electrolyte mass transport conditions on structurally well defined

• serving as chemically inert and stable and electrically conducting substrate, which in turn is deposited on a Si prism. The Au films have to be thin enough to be FTIR transparent and thick enough to exhibit sufficient electric conductivity and fully cover the Si substrate. The gold thin film was prepared

Analytical development and optimization of a graphene–solution interface capacitance model

• Hediyeh Karimi,
• Rasoul Rahmani,
• Reza Mashayekhi,
• Leyla Ranjbari,
• Amir H. Shirdel,
• Niloofar Haghighian,
• Parisa Movahedi,
• Moein Hadiyan and
• Razali Ismail

Beilstein J. Nanotechnol. 2014, 5, 603–609, doi:10.3762/bjnano.5.71

• -based devices, graphene with its outstanding properties such as consuming less energy and faster heat dissipating show a great promise in electrolyte-gated graphene field-effect transistors (EGFETs) [20]. An EGFET fabricated on a SiO2/Si substrate with gold source and drain electrodes and a graphene

Encapsulation of nanoparticles into single-crystal ZnO nanorods and microrods

• Jinzhang Liu,
• Marco Notarianni,
• Llew Rintoul and
• Nunzio Motta

Beilstein J. Nanotechnol. 2014, 5, 485–493, doi:10.3762/bjnano.5.56

• experiment NDs from isopropanol solution were dispersed onto both ZnO nano/microrods and a Si substrate. If a lithography technique is employed to grow ordered ZnO nanorods onto a lattice-constant-matched substrate, nanoparticles on the substrate can be avoided and the size of nanorod cavity can be well

• process (20 mM, 6 h), as evidenced by the top-view image in Figure 2b and the side-view image in Figure 1c. Among the nanorods, few show incomplete encapsulation of agglomerated NDs. as can be seen in Figure 2d. We cut the Si substrate to take side-view images. Some nanorods were fractured at the edge of

Plasma-assisted synthesis and high-resolution characterization of anisotropic elemental and bimetallic core–shell magnetic nanoparticles

• M. Hennes,
• A. Lotnyk and
• S. G. Mayr

Beilstein J. Nanotechnol. 2014, 5, 466–475, doi:10.3762/bjnano.5.54

• supplementary coating layer in chamber B, while traveling through the metallic vapor generated by SG2, which is carefully kept below supersaturation. Finally, particles are extracted in C, where they are deposited onto a Si substrate or TEM grids for further analysis. Gas dynamics and NP transport Particle

Fullerenes as adhesive layers for mechanical peeling of metallic, molecular and polymer thin films

• Maria B. Wieland,
• Anna G. Slater,
• Barry Mangham,
• Neil R. Champness and
• Peter H. Beton

Beilstein J. Nanotechnol. 2014, 5, 394–401, doi:10.3762/bjnano.5.46

• −1 correspond to the Si substrate, the peak at 720 cm−1 and the region between 1400 and 1600 cm−1 with the relatively sharp line at around 1470 cm−1 are characteristic for C60; [31][32] insert: fluorescence emission spectrum (excitation wavelength = 532 nm) of the same samples with the characteristic