Purification of ethanol for highly sensitive self-assembly experiments

• Kathrin Barbe,
• Martin Kind,
• Christian Pfeiffer and
• Andreas Terfort

Beilstein J. Nanotechnol. 2014, 5, 1254–1260, doi:10.3762/bjnano.5.139

• onto glass supports. Since the sensitivity of the sensors inversely scales with the film thickness, typically thicknesses just above the level of the formation of dense films were chosen (ca. 25 nm). Adhesion of these films was promoted by prior evaporation of a chromium layer of 2 nm thickness. The

Nanocavity crossbar arrays for parallel electrochemical sensing on a chip

• Enno Kätelhön,
• Dirk Mayer,
• Marko Banzet,
• Andreas Offenhäusser and
• Bernhard Wolfrum

Beilstein J. Nanotechnol. 2014, 5, 1137–1143, doi:10.3762/bjnano.5.124

• depositing a titanium/platinum/chromium stack that features the thicknesses 7/50/7 nm by using electron beam evaporation. In the next step, 50 nm thick chromium sacrificial layers are deposited at the positions of the future intersections. These layers define the geometric features of the nanocavities

• . Afterwards, the top electrodes are fabricated from an electron-beam evaporated stack of chromium/platinum/titanium stack of the thicknesses 7/50/7 nm. Subsequently, a passivation composed of alternating layers. SiO2/Si3N4/SiO2 is deposited via plasma enhanced chemical vapor deposition [38]. In the next step

• , access holes are etched through the passivation directly down onto the chromium sacrificial layer by reactive ion etching. The chromium is then fully removed in an isotropic wet etch using chrome etch solution. Electrochemical methods Electrochemical characterization is either performed via cyclic

Designing magnetic superlattices that are composed of single domain nanomagnets

• Derek M. Forrester,
• Feodor V. Kusmartsev and
• Endre Kovács

Beilstein J. Nanotechnol. 2014, 5, 956–963, doi:10.3762/bjnano.5.109

• have been successfully doped (with, for example, vanadium or chromium [2]) to lower the saturation magnetization of the compound. In doing so the energy barrier between stable states of the magnetization remains at a surmountable level. This is of high significance for designing magnetic logic elements

Integration of ZnO and CuO nanowires into a thermoelectric module

• Dario Zappa,
• Simone Dalola,
• Guido Faglia,
• Elisabetta Comini,
• Matteo Ferroni,
• Caterina Soldano,
• Vittorio Ferrari and
• Giorgio Sberveglieri

Beilstein J. Nanotechnol. 2014, 5, 927–936, doi:10.3762/bjnano.5.106

• material for the probing tips, Chromel was used. Chromel is an alloy of nickel and chromium, which exhibits a positive absolute Seebeck coefficient of about 28.1 μV/K [39] and is commonly used with Alumel to form K-type thermocouples. The voltage ΔV, measured at the ends of the probing tips, is

Hole-mask colloidal nanolithography combined with tilted-angle-rotation evaporation: A versatile method for fabrication of low-cost and large-area complex plasmonic nanostructures and metamaterials

• Jun Zhao,
• Bettina Frank,
• Frank Neubrech,
• Chunjie Zhang,
• Paul V. Braun and
• Harald Giessen

Beilstein J. Nanotechnol. 2014, 5, 577–586, doi:10.3762/bjnano.5.68

• about 98 °C for around 3 min to fix the PS spheres on the polymer film. After drying the sample with nitrogen, the PMMA layer is now covered with well separated and randomly arranged PS spheres. Subsequently, a thin film consisting of 5 nm chromium (Cr) and 20 nm gold (Au) is evaporated on top of the

Surface assembly and nanofabrication of 1,1,1-tris(mercaptomethyl)heptadecane on Au(111) studied with time-lapse atomic force microscopy

• Tian Tian,
• Burapol Singhana,
• Lauren E. Englade-Franklin,
• Xianglin Zhai,
• T. Randall Lee and
• Jayne C. Garno

Beilstein J. Nanotechnol. 2014, 5, 26–35, doi:10.3762/bjnano.5.3

• chlorochromate (26.89 g, 124.7 mmol) and silica gel (30 mg) were mixed and suspended in 100 mL of dry CH2Cl2. The solution of 1-octadecanol (20.13 g, 74.42 mmol) in CH2Cl2 was added into the stirred mixture. Stirring was continued for 4 h at rt, and the black chromium compounds were removed by passage through a

Preparation of electrochemically active silicon nanotubes in highly ordered arrays

• Tobias Grünzel,
• Young Joo Lee,
• Karsten Kuepper and
• Julien Bachmann

Beilstein J. Nanotechnol. 2013, 4, 655–664, doi:10.3762/bjnano.4.73

• , phosphoric acid, copper(II) chloride dihydrate, chromium(VI) oxide, ethanol, hydrochloric acid, perchloric acid, argon, and dioxygen, were purchased from commercial suppliers and used as received. Ozone was generated from dioxygen in a generator BMT 803N from BMT Messtechnik. Aluminum (99.999%) was purchased

Strong spin-filtering and spin-valve effects in a molecular V–C₆₀–V contact

• Mohammad Koleini and
• Mads Brandbyge

Beilstein J. Nanotechnol. 2012, 3, 589–596, doi:10.3762/bjnano.3.69

• different sites on the C60 molecule. It can be seen that nickel has the strongest binding energy but with zero total magnetization (MT), and thus, is probably not interesting for investigations of spin transport. On the other hand, chromium enjoys the largest MT, due to its largest unpaired electronic

Channeling in helium ion microscopy: Mapping of crystal orientation

• Vasilisa Veligura,
• Gregor Hlawacek,
• Raoul van Gastel,
• Harold J. W. Zandvliet and
• Bene Poelsema

Beilstein J. Nanotechnol. 2012, 3, 501–506, doi:10.3762/bjnano.3.57

• PE of 15 keV. This increases the scattering probability and results in a better signal-to-noise ratio for ion-channeling contrast images. Commercially available polycrystalline gold{111} films on glass, with a chromium interlayer, were flame annealed in a hydrogen flame before the samples were loaded

Mapping mechanical properties of organic thin films by force-modulation microscopy in aqueous media

• Jianming Zhang,
• Zehra Parlak,
• Carleen M. Bowers,
• Terrence Oas and
• Stefan Zauscher

Beilstein J. Nanotechnol. 2012, 3, 464–474, doi:10.3762/bjnano.3.53

• the cantilever. Sample Preparation Gold deposition Silicon wafers (Virginia semiconductor, Part 325S119656) were washed in acetone, ethanol and DI water, and completely dried before use. A 45 nm gold layer with a 5 nm chromium adhesion layer was deposited on the silicon surface by using an e-beam

Colloidal lithography for fabricating patterned polymer-brush microstructures

• Tao Chen,
• Debby P. Chang,
• Rainer Jordan and
• Stefan Zauscher

Beilstein J. Nanotechnol. 2012, 3, 397–403, doi:10.3762/bjnano.3.46

• were prepared by thermal evaporation under a vacuum of 4 × 10−7 Torr. For this purpose an adhesion layer of chromium (50 Å) followed by a layer of gold (600 Å) was evaporated onto silicon wafers. Before deposition, silicon wafers were cleaned in a mixture of H2O2/H2SO4 (1:3, v/v) at 80 °C (“piranha

Models of the interaction of metal tips with insulating surfaces

• Thomas Trevethan,
• Matthew Watkins and
• Alexander L. Shluger

Beilstein J. Nanotechnol. 2012, 3, 329–335, doi:10.3762/bjnano.3.37

• atomic resolution. Chromium and tungsten tips are used to image the NaCl(001) and MgO(001) surfaces. The interaction of the tips with the surface is simulated by using density-functional-theory calculations employing a mixed Gaussian and plane-wave basis and cluster-tip models. In each case, the apex of

• the metal cluster interacts more attractively with anions in the surfaces than with cations, over the range of typical imaging distances, which leads to these sites being imaged as raised features (bright) in constant-frequency-shift images. We compare the results of the interaction of a chromium tip

• localization and reconfiguration and a tip apex that is not truly metallic. It has been demonstrated that a chromium-coated tip is capable of imaging the bulk NaCl(001) surface with atomic resolution, at relatively large tip–surface separations (i.e., >5 Å), reducing the potential for the tip to become

Combining nanoscale manipulation with macroscale relocation of single quantum dots

• Francesca Paola Quacquarelli,
• Richard A. J. Woolley,
• Martin Humphry,
• Jasbiner Chauhan,
• Philip J. Moriarty and
• Ashley Cadby

Beilstein J. Nanotechnol. 2012, 3, 324–328, doi:10.3762/bjnano.3.36

• spectrum was taken from that area. The two corresponding spectra are shown in Figure 3c. Both spectra contain several sharp features between 650 nm and 750 nm arising from photoluminescence (PL) caused by the sapphire substrate and are likely due to chromium ions [19]. The PL spectrum taken on the

• recorded to optically identify the emission as being that from a single QD [20][21]. Due to limitations in the collection optics it was not possible to see blinking in our sample. The PL contamination, caused by chromium defects in the sapphire, limits the use of this substrate to QDs with peak emission

• excitation with the 442 nm line of a He:Cd laser. The 610 nm QD emission can be clearly seen in the black spectrum. The emission above 650 nm is due to chromium contamination in the sapphire substrate. (a) The automation algorithm identifies the experimental cells from the macroscopic reference grid, (b

Analysis of fluid flow around a beating artificial cilium

• Mojca Vilfan,
• Gašper Kokot,
• Andrej Vilfan,
• Natan Osterman,
• Blaž Kavčič,
• Igor Poberaj and
• Dušan Babič

Beilstein J. Nanotechnol. 2012, 3, 163–171, doi:10.3762/bjnano.3.16

• in a cleaning solution (H2O/HNO3/HCl = 2:1:3) and etched with a standard chromium etchant (Sigma-Aldrich). The remaining photoresist was then removed with acetone and with delicate mechanical force, revealing the remaining nickel anchoring sites on the slide. The nickel dots were 5 μm in diameter and

X-ray spectroscopy characterization of self-assembled monolayers of nitrile-substituted oligo(phenylene ethynylene)s with variable chain length

• Hicham Hamoudi,
• Ping Kao,
• Alexei Nefedov,
• David L. Allara and
• Michael Zharnikov

Beilstein J. Nanotechnol. 2012, 3, 12–24, doi:10.3762/bjnano.3.2

• protocols [69]. The purity of all the compounds was checked by NMR. The gold substrates were prepared by thermal evaporation of 100–200 nm of gold (99.99% purity) onto polished single crystal silicon (100) wafers (Silicon Sense) primed with either a 5 nm titanium or a 5 nm chromium adhesion layer. The

Self-assembled monolayers and titanium dioxide: From surface patterning to potential applications

• Yaron Paz

Beilstein J. Nanotechnol. 2011, 2, 845–861, doi:10.3762/bjnano.2.94

• through-mask exposure techniques. Indeed, exposure of OTS-coated TiO2 to 254 nm light through a quartz mask covered with chromium stripes (40 µm in width and distance) caused a complete degradation of the alkyl chains, including those in the “dark” regions [67]. This does not necessarily contradict the

Plasmonic nanostructures fabricated using nanosphere-lithography, soft-lithography and plasma etching

• Manuel R. Gonçalves,
• Taron Makaryan,
• Fabian Enderle,
• Stefan Wiedemann,
• Alfred Plettl,
• Othmar Marti and
• Paul Ziemann

Beilstein J. Nanotechnol. 2011, 2, 448–458, doi:10.3762/bjnano.2.49

• for reactive ion etching, a film of chromium was evaporated on top of the PS beads. The mask obtained was in the form of a hexagonal array of triangular structures. Measurements of the topography by atomic force microscopy (WITec Alpha 300 AFM in AC mode) typically gave larger thickness values than