Electron-beam patterned self-assembled monolayers as templates for Cu electrodeposition and lift-off

• Zhe She,
• Andrea DiFalco,
• Georg Hähner and
• Manfred Buck

Beilstein J. Nanotechnol. 2012, 3, 101–113, doi:10.3762/bjnano.3.11

• shows a compilation of AFM images comparing the structure as deposited on a MBP0 patterned Au/Si substrate with the one transferred to the epoxy glue. Parallel lines about 1 μm apart were written into the SAM by e-beam lithography. As inferred from the difference between the grooves, where the cross

• on Au/Si. Potentials of I–t curves in (a) are −0.5 V (black line), −0.6 V (red dashed line) and −0.7 V (green dotted line) and in (b) −0.7 V for 1 s, −0.35 V for 10 s on MBP0/Au/Si. For comparison an I–t curve for a clean Au/Si substrate and identical deposition conditions is shown in the inset. (c,d

• height profile along the line. Deposition conditions: −0.7 V for 1 s, −0.25 V for 20 s (a); −0.7 V for 1 s, −0.35 V for 10 s (b). SEM images of a SAM templated copper deposit on the original MBP0 coated Au/Si substrate (a) and after transfer to epoxy glue (b). The passivating line of the cross-linked SAM

Direct-write polymer nanolithography in ultra-high vacuum

• Woo-Kyung Lee,
• Minchul Yang,
• Arnaldo R. Laracuente,
• William P. King,
• Lloyd J. Whitman and
• Paul E. Sheehan

Beilstein J. Nanotechnol. 2012, 3, 52–56, doi:10.3762/bjnano.3.6

• thicknesses deposited in UHV. The lower deposition temperature also reduces the risk of thermal damage when applied to pre-fabricated devices. While heating the probe to the vacuum melting temperature of the PDDT, the tip was rasterized across the “as is” native oxide Si substrate at different speeds. We

• the relatively high speed of 20 µm/s, only a single monolayer is deposited as shown by the line average to the right of the image. Lower speeds deposit thicker polymer lines as shown by line averages in (c). The polymer deposit heights and widths of PDDT deposited onto Si substrate (non-UHV prepared

• ) as a function of scanning speed. Both the height and width decrease monotonically with tip speed. (a) Deposition onto the UHV prepared Si substrate in UHV shows the polymer lying on its side. (b) Polymer deposited across a Si step edge an atom thick. (c) The cross section [pale blue line in (b

Mechanical characterization of carbon nanomembranes from self-assembled monolayers

• Xianghui Zhang,
• André Beyer and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2011, 2, 826–833, doi:10.3762/bjnano.2.92

• position or tilt. (a) Schematic diagram of a bulge test in AFM; (b) Schematic of a biphenylthiol CNM on a window-structured Si substrate, which is suspended over an orifice; (c) AFM image of a nonpressurized CNM in contact mode and the line profile with a downward deformation of 200 nm; (d) AFM image of

Nanostructured, mesoporous Au/TiO₂ model catalysts – structure, stability and catalytic properties

• Matthias Roos,
• Dominique Böcking,
• Kwabena Offeh Gyimah,
• Gabriela Kucerova,
• Joachim Bansmann,
• Johannes Biskupek,
• Ute Kaiser,
• Nicola Hüsing and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2011, 2, 593–606, doi:10.3762/bjnano.2.63

• mode. By mechanically removing part of the Au/TiO2 film, we generated a free-standing edge of the film on the Si substrate around the sample center, whose height was measured by AFM. Evaluation of single line profiles across the step edge between the bare Si substrate and the region of the intact Au

• measurements on Au/TiO2 thin-film catalysts. These probe the entire film thickness, and even into the Si substrate, as evident from the presence of a visible Si peak. Hence, despite a similar Au loading process and process parameters, the DP process leads to significantly higher Au contents on the TiO2 film

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

• when the tip is on top of the Co wire and to about −320 mV in the case of the Si substrate. Thus, according to these results, by measuring the frequency shift on top of the Co wire at Vbias = 320 mV (horizontal black dashed line) we should detect only the magnetic signal without any electrostatic

Formation of precise 2D Au particle arrays via thermally induced dewetting on pre-patterned substrates

• Dong Wang,
• Ran Ji and
• Peter Schaaf

Beilstein J. Nanotechnol. 2011, 2, 318–326, doi:10.3762/bjnano.2.37

• symmetry (substrate B). SEM images of induced particles on the flat SiO2/Si substrate after dewetting of the 5 nm (a) and 60 nm (b) thick Au films. (c) Histograms of particle size distributions produced by the dewetting of the 5 nm, 10 nm, 20 nm, 30 nm, 40 nm, and 60 nm thick Au films on the flat SiO2/Si

• substrate A have a spatial period of 513 nm and a depth of 150 nm. The holes in the substrate B have the same spatial period of 513 nm, a diameter of about 490 nm, and a depth of 120 nm. Figure 2 shows the SEM images of the Au particles formed from the 5 nm and 60 nm thick Au films on a flat SiO2/Si

• substrate. Usually, flat substrates lead to a broad distribution of particle size and spacing of the dewetted particles. Figure 2c shows the particle size distributions produced by dewetting of Au films with thicknesses from 5 nm to 60 nm on the flat substrates. Both, mean particle size and the width

Extended X-ray absorption fine structure of bimetallic nanoparticles

• Carolin Antoniak

Beilstein J. Nanotechnol. 2011, 2, 237–251, doi:10.3762/bjnano.2.28

• -hexane with surfactants, precipitated out and centrifuged once again. This can be repeated several times, until a stable dispersion of nanoparticles in n-hexane is obtained. The nanoparticles can be brought onto a naturally oxidised Si substrate using the spin coating technique, dip coating or just by

Single-pass Kelvin force microscopy and dC/dZ measurements in the intermittent contact: applications to polymer materials

• Sergei Magonov and
• John Alexander

Beilstein J. Nanotechnol. 2011, 2, 15–27, doi:10.3762/bjnano.2.2

• on the polymer films by a sharp wooden stick and we verified that a substrate-specific morphology was present at the bottom of scratches. At the scratched locations one can measure the film thickness and a relative electrical response of the polymer and Si substrate. All prepared samples were glued

• illustrated in Figure 2B which shows the dependence of phase changes as a function of DC bias voltage between a conducting probe and different locations of the F14H20 adsorbate on Si substrate. The phase-versus-DC-bias curve (colored blue) was detected when the probe was over a domain of the toroid-like self

• voltages needed for nullification of the electrostatic is the main function of KFM. The topography and surface potential images, which were recorded on the F14H20 adsorbate on Si substrate, are presented in Figure 3. These images were obtained with Asp just above (Figure 3A) and below (Figure 3B) its value

Magnetic coupling mechanisms in particle/thin film composite systems

• Giovanni A. Badini Confalonieri,
• Philipp Szary,
• Durgamadhab Mishra,
• Maria J. Benitez,
• Mathias Feyen,
• An Hui Lu,
• Leonardo Agudo,
• Gunther Eggeler,
• Oleg Petracic and
• Hartmut Zabel

Beilstein J. Nanotechnol. 2010, 1, 101–107, doi:10.3762/bjnano.1.12

• Kohlenforschung, D-45470 Mülheim an der Ruhr, Germany Institut für Werkstoffe, Ruhr-Universität Bochum, D-44780 Bochum, Germany 10.3762/bjnano.1.12 Abstract Magnetic γ-Fe2O3 nanoparticles with a mean diameter of 20 nm and size distribution of 7% were chemically synthesized and spin-coated on top of a Si

• -substrate. As a result, the particles self-assembled into a monolayer with hexagonal close-packed order. Subsequently, the nanoparticle array was coated with a Co layer of 20 nm thickness. The magnetic properties of this composite nanoparticle/thin film system were investigated by magnetometry and related

Preparation and characterization of supported magnetic nanoparticles prepared by reverse micelles

• Ulf Wiedwald,
• Luyang Han,
• Johannes Biskupek,
• Ute Kaiser and
• Paul Ziemann

Beilstein J. Nanotechnol. 2010, 1, 24–47, doi:10.3762/bjnano.1.5

• measured for CoCl2 loaded PS(1779)-P2VP(857) reverse micelles. All spectra shown in Figure 5 are normalized to the total Si-2p signal intensity of the substrate. In the initial state PS-P2VP molecules dominate the survey scan proving the continuous coverage of the Si substrate by reverse micelles. The Co

• micelle shell, strongly decreases relative to the Si substrate even after oxygen exposure for only 30 s. After 5 min exposure time, the C-1s intensity dropped below the detection limit, while after 10 min a clear Co2+ spectrum can be observed. At this stage the particles simultaneously nucleate to form Co

• Figure 11 (b) which nicely demonstrates the validity of the approach. Note that the larger error bars of Co NPs on Si substrate are due to the lower saturation magnetization of the sample (10–9 Am2). 3.3 FePt alloy particles For the magnetic characterization of FePt alloy particles we chose X-ray