Review: Electrostatically actuated nanobeam-based nanoelectromechanical switches – materials solutions and operational conditions

• Liga Jasulaneca,
• Jelena Kosmaca,
• Raimonds Meija,
• Jana Andzane and
• Donats Erts

Beilstein J. Nanotechnol. 2018, 9, 271–300, doi:10.3762/bjnano.9.29

• difficult to fabricate due to their high intrinsic stress, large surface roughness and grain size, inherent porosity, and low strength. To date, there are rather few reports on metallic NEM switches [17][18][114][115]. Molybdenum is attractive as a NEM switch material due to its high melting temperature

• layer. Another concern is the edge roughness of the as-fabricated beams that leads to variation in jump-in voltages and contact resistances for a given design [18]. To our knowledge, metal alloys used as NEM switching elements have been reported in only one study using a TiW switching element and W as

Liquid-crystalline nanoarchitectures for tissue engineering

• Baeckkyoung Sung and
• Min-Ho Kim

Beilstein J. Nanotechnol. 2018, 9, 205–215, doi:10.3762/bjnano.9.22

• modulus, porosity, surface roughness, and local anisotropy [102]. LC hydrogels and implants in nematic and smectic-A phases LC-ordered anisotropic gels have great potential to be directly applied to regenerative medicine therapeutics, due to their intrinsic tissue compatibility. Thermally or

Dopant-stimulated growth of GaN nanotube-like nanostructures on Si(111) by molecular beam epitaxy

• Alexey D. Bolshakov,
• Alexey M. Mozharov,
• Georgiy A. Sapunov,
• Igor V. Shtrom,
• Nickolay V. Sibirev,
• Vladimir V. Fedorov,
• Evgeniy V. Ubyivovk,
• Maria Tchernycheva,
• George E. Cirlin and
• Ivan S. Mukhin

Beilstein J. Nanotechnol. 2018, 9, 146–154, doi:10.3762/bjnano.9.17

• the field of photovoltaics. In case of silicon-based solar cells (SCs), reflection can be reduced from 30% (pure Si) down to 3% without deposition of multilayer antireflection coatings or involvement of complicated postgrowth techniques generally used for modification of the SC surface roughness [9

Growth model and structure evolution of Ag layers deposited on Ge films

• Arkadiusz Ciesielski,
• Lukasz Skowronski,
• Ewa Górecka,
• Jakub Kierdaszuk and
• Tomasz Szoplik

Beilstein J. Nanotechnol. 2018, 9, 66–76, doi:10.3762/bjnano.9.9

• [13][14]. The SPP wave propagation length depends on the permittivity of the metal film, but also on its surface roughness, which is responsible for scattering losses. Thin silver layers deposited on glass substrates usually exhibit an island growth [15]. One way of fabricating smooth and thermally

• stable Ag-based layers of thickness less than 15 nm on fused silica substrates is magnetron cosputtering of silver and aluminum. Surface root-mean-square (RMS) roughness of 15 nm Al-doped Ag films with an Al atomic concentration of 4% have been recently reported to be equal to 0.4 nm [16]. However, in

• conditions [18] and with a Ge nucleation film, they are smoother than layers of similar thickness deposited directly on glass [19] and have significantly lower mean grain size [20]. The reduction of scattering losses due to a temporary decrease of RMS roughness to 0.2 nm was reported for an e-beam evaporated

Beyond Moore’s technologies: operation principles of a superconductor alternative

• Igor I. Soloviev,
• Nikolay V. Klenov,
• Sergey V. Bakurskiy,
• Mikhail Yu. Kupriyanov,
• Alexander L. Gudkov and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2017, 8, 2689–2710, doi:10.3762/bjnano.8.269

Exploring wear at the nanoscale with circular mode atomic force microscopy

• Olivier Noel,
• Aleksandar Vencl and
• Pierre-Emmanuel Mazeran

Beilstein J. Nanotechnol. 2017, 8, 2662–2668, doi:10.3762/bjnano.8.266

• in contact mode before and after the wear experiment, at the same location of the sample (Figure 3A,B); 2) as the wear track depth is of the same order of magnitude as the peak-to-valley roughness, it is necessary to subtract the height of these two AFM images to highlight the wear track; 3) relevant

• image is not perfectly flat outside the wear track, but the process considerably reduces the effect of the roughness for determining the wear volume (Figure 3C); 4) once the difference image is computed, the average height is calculated as a function of the distance from the center of the circular wear

• wear volumes at the nanoscale are accessible using an image processing method. The used strategy to calculate the wear volume consists of attenuating the roughness of the surface that is of the same order as the nanometer dimension of the wear track (which may interfere in the calculation of the wear

Direct writing of gold nanostructures with an electron beam: On the way to pure nanostructures by combining optimized deposition with oxygen-plasma treatment

• Domagoj Belić,
• Mostafa M. Shawrav,
• Emmerich Bertagnolli and
• Heinz D. Wanzenboeck

Beilstein J. Nanotechnol. 2017, 8, 2530–2543, doi:10.3762/bjnano.8.253

• a very modest increase (EF ≈ 1.1). We note that, in this way, postdeposition O-plasma treatment may work as a leveller of compositional gradient in inhomogeneous planar FEBID structures. Furthermore, the increased roughness and SEM-brightness of the nanostructures’ surfaces, seen in Figure 4d and

Interface conditions of roughness-induced superoleophilic and superoleophobic surfaces immersed in hexadecane and ethylene glycol

• Yifan Li,
• Yunlu Pan and
• Xuezeng Zhao

Beilstein J. Nanotechnol. 2017, 8, 2504–2514, doi:10.3762/bjnano.8.250

• that can affect the drag of fluid flow. For surfaces with different oleophobicity, the boundary slip at the solid–oil interface is mostly larger than that at the solid–water interface. Roughness is a key factor for the wettability of superoleophilic/superoleophobic surfaces, and it has been found to

• affect the effective value of slip length in measurements. Moreover, there are no studies on the effect of roughness on slip at interfaces between oil and superoleophilic/superoleophobic surfaces. A theoretical description of the real surface roughness is yet to be found. Results show that the effective

• slip length is negative and decreases with an increasing root mean squared (RMS) roughness of surfaces, as the increasing roughness enhances the area with discontinuous slip at the solid–liquid interface. The underlying mechanisms are analyzed. The amplitude parameters of surface roughness could

Comparing postdeposition reactions of electrons and radicals with Pt nanostructures created by focused electron beam induced deposition

• Julie A. Spencer,
• Michael Barclay,
• Miranda J. Gallagher,
• Robert Winkler,
• Ilyas Unlu,
• Yung-Chien Wu,
• Harald Plank,
• Lisa McElwee-White and
• D. Howard Fairbrother

Beilstein J. Nanotechnol. 2017, 8, 2410–2424, doi:10.3762/bjnano.8.240

• roughness. Wnuk et al. [28] subjected deposits created from Me2Au(acac) to AH and/or atomic oxygen (AO). AH removed all of the O atoms and the majority of C atoms from the deposit while AO removed all of the C atoms far more efficiently than AH, but with some accompanying Au oxidation. However, exposure to

• -line leveling, surface roughness, profile extraction and 3D rendering was carried out with Pico Image Basic 5.0.2 software. Deposition, characterization and treatment of FEBID structures in the FIB Nova 200 system In these experiments, FEBID was performed on a FIB Nova 200 dual beam microscope (FEI

• times (TET) per pixel. The deposits were created on a 1 × 1 cm² silicon wafer (3 nm surface oxide) and spaced 5 µm apart from one another. The height and roughness characterization was done with via AFM (FastScan Bio, Bruker AXS, USA) in tapping mode and postprocessed with Gwyddion 2.44 software

Increasing the stability of DNA nanostructure templates by atomic layer deposition of Al₂O₃ and its application in imprinting lithography

• Hyojeong Kim,
• Kristin Arbutina,
• Anqin Xu and
• Haitao Liu

Beilstein J. Nanotechnol. 2017, 8, 2363–2375, doi:10.3762/bjnano.8.236

• film (Figure 5). We note that the polymer residue was not observed on the surface of the DNA nanotube master template with the ca. 5 nm thick Al2O3 film even after the 5th replication. The surface roughness of Al2O3 film grown using ALD slowly increases as the number of cycles goes up [49]. Therefore

• Information File 1). In case of the DNA origami triangles, the DNA nanostructures with the average height of 1.68 nm (n = 10) were barely seen and the height profile along the individual DNA triangles also showed the significant increase of roughness (Figure S10d, Supporting Information File 1). These results

Surfactant-induced enhancement of droplet adhesion in superhydrophobic soybean (Glycine max L.) leaves

• Oliver Hagedorn,
• Ingo Fleute-Schlachter,
• Hans Georg Mainx,
• Viktoria Zeisler-Diehl and
• Kerstin Koch

Beilstein J. Nanotechnol. 2017, 8, 2345–2356, doi:10.3762/bjnano.8.234

• of wax platelets composed of n-hexatriacontane [43]. Smaller sizes of wax crystals reduce the surface roughness and the contact angle and also increase the adherence of the droplets to the surfaces, as indicated by the hysteresis or given tilt angles [42][43]. Surfactants with a high HLB value (XP ED

Expanding the molecular-ruler process through vapor deposition of hexadecanethiol

• Alexandra M. Patron,
• Timothy S. Hooker,
• Daniel F. Santavicca,
• Corey P. Causey and
• Thomas J. Mullen

Beilstein J. Nanotechnol. 2017, 8, 2339–2344, doi:10.3762/bjnano.8.233

• attributed to C16 molecules bound to a MHDA monolayer via cupric ions. The morphology of these islands is consistent with previous AFM topographic images of solution-deposited Cu-ligated MHDA-C16 bilayers [27]. This surface morphology results in a RMS roughness of 3.2 ± 0.5 nm, which is considerably larger

• than previously reported RMS roughnesses for MHDA monolayers (ca. 0.1 nm) and MHDA bilayers (1.0 nm) [32]. Similar morphology and slightly higher coverages of the C16 islands are observed when C16 is deposited from solution at 80 °C (Figure S1, Supporting Information File 1). Given the roughness and

• deposition results in a RMS roughness of 1.3 ± 0.1 nm, which is smaller than a Cu-ligated MHDA-C16 bilayer formed via solution deposition. Further, the surface coverage of these C16 islands (69.9 ± 1.8%) is considerably higher than the C16 surface coverage for the MHDA-C16 bilayer formed via solution

Tailoring the nanoscale morphology of HKUST-1 thin films via codeposition and seeded growth

• Landon J. Brower,
• Lauren K. Gentry,
• Amanda L. Napier and
• Mary E. Anderson

Beilstein J. Nanotechnol. 2017, 8, 2307–2314, doi:10.3762/bjnano.8.230

• control the film morphology for surMOFs of HKUST-1 fabricated by codeposition and seeded deposition. Time and temperature were investigated to observe film formation, to control film thickness, and to tune morphology. Film thickness was investigated by ellipsometry, while film structure and film roughness

• film [11][12]. For surMOF film growth via LBL deposition, it was found that temperature and surface chemistry (terminal functional group of SAM) control the crystal face growth of the crystallites on the substrate [11][12][15][16][17]. This provides some degree of control over roughness, particle size

• , surface coverage, and film thickness. In juxtaposition to the LBL method that generated films and crystallites in the sub-100 nm regime, MOF film deposition from mother liquor solutions, which are used to solvothermally produce powders, yield films that have thickness, roughness, and grain sizes on the

Fabrication of gold-coated PDMS surfaces with arrayed triangular micro/nanopyramids for use as SERS substrates

• Jingran Zhang,
• Yongda Yan,
• Peng Miao and
• Jianxiong Cai

Beilstein J. Nanotechnol. 2017, 8, 2271–2282, doi:10.3762/bjnano.8.227

• shown in Figure 10a,b. The average size of the nanoparticles for a gold-film thickness of 10 and 50 nm is approximately 45 and 90 nm, respectively. The roughness of the PDMS surface with a gold film thickness of 10 and 50 nm is 1.9 and 1.2 nm, respectively, under the same measurement parameters. More

• ) with an enlarged image of the local position and the Raman spectra of R6G molecules at a concentration of 10−6 M on the commercial Q-SERS substrate. The nanoparticle diameter was found to be approximately 150 nm and the roughness of the Q-SERS substrate was 9.5 nm. The Raman intensity of the 1362 cm−1

The interplay between spin densities and magnetic superexchange interactions: case studies of mono- and trinuclear bis(oxamato)-type complexes

• Azar Aliabadi,
• Bernd Büchner,
• Vladislav Kataev and
• Tobias Rüffer

Beilstein J. Nanotechnol. 2017, 8, 2245–2256, doi:10.3762/bjnano.8.224

• of spintronic devices in detail, we focused on the synthesis of type-III complexes as models of SMMs with the aim to deposit them as thin films on surfaces. Already in 2006, we reported on the deposition of thin films of a type-III complex by spin coating [27], although the surface roughness of the

Angstrom-scale flatness using selective nanoscale etching

• Takashi Yatsui,
• Hiroshi Saito and
• Katsuyuki Nobusada

Beilstein J. Nanotechnol. 2017, 8, 2181–2185, doi:10.3762/bjnano.8.217

• obtained 0 min, 5 min, and 35 min after wet etching. In the AFM images, the surface roughness (Ra) was found to be 0.161, 0.134, and 0.100 nm, respectively (solid circles in Figure 3d). In addition, we checked the Ra where light was not irradiated with the Ca(ClO)2 solution and found that its value was

• unchanged (0.139 nm for before and 0.138 nm for after etching; solid squares in Figure 3d). These results indicate that near-field wet etching decreased the surface roughness. We also plotted the root mean square (RMS) roughness values in Figure 3d. Although the value is not the same, they have a similar

• , further control of the selective etching at smaller scales should be achievable by controlling mean free path (i.e. the partial pressure of the gas). Schematic of the near-field etching process. Experimental setup for the near-field wet etching technique. Time dependence of surface roughness using a

Ta₂N₃ nanocrystals grown in Al₂O₃ thin layers

• Krešimir Salamon,
• Maja Buljan,
• Iva Šarić,
• Mladen Petravić and
• Sigrid Bernstorff

Beilstein J. Nanotechnol. 2017, 8, 2162–2170, doi:10.3762/bjnano.8.215

• a range of parallel Bragg sheets centred in the specular plane (qy = 0). These kind of scattering maxima are usually observed from periodic multilayers with correlated roughness among the interfaces [25][26]. The angular positions of the Bragg sheets yield the periodicity of the corresponding

• [28] and roughness according to the Nevot and Croce model [29]. In the simulations we assumed a model with the nominal multilayer structure, while the periodicity, thickness of the metallic and spacer layers, their densities and roughness were varied. The last two columns of Table 1 show the results

• films, showing that the depositions resulted in minimal imperfections of the layers. For the films annealed up to 800 °C we observed a slight increase in interface roughness and a slight decrease in density contrast between the adjacent layers for both types of MLs. Furthermore, clear Bragg peaks

A comparative study of the nanoscale and macroscale tribological attributes of alumina and stainless steel surfaces immersed in aqueous suspensions of positively or negatively charged nanodiamonds

• Colin K. Curtis,
• Antonin Marek,
• Alex I. Smirnov and
• Jacqueline Krim

Beilstein J. Nanotechnol. 2017, 8, 2045–2059, doi:10.3762/bjnano.8.205

• consistent with strong attachment of NDs and/or chemical changes to the surfaces. AFM images of the surfaces indicated slight increases in the surface roughness upon an exposure to both +ND and −ND suspensions. A suggested mechanism for these observations is that carboxylated −NDs from aqueous suspensions

• ,yi). The height profiles were quantified by the rms roughness value σ, which is virtually always dependent on the size of the area sampled below a characteristic lateral correlation length ξ. For a self-affine fractal surface the rms roughness increases with the lateral length of the sampled area as

• σ LH, where H is the roughness exponent whose value lies between 0 and 1. Fractal surfaces are often characterized by self-affine fractal dimension D = 3 − H [31][32][33]. Self-affine surfaces have an upper horizontal cut-off length (the lateral correlation length (ξ)) above which the rms roughness

Advances and challenges in the field of plasma polymer nanoparticles

• Andrei Choukourov,
• Pavel Pleskunov,
• Daniil Nikitin,
• Valerii Titov,
• Artem Shelemin,
• Mykhailo Vaidulych,
• Anna Kuzminova,
• Pavel Solař,
• Jan Hanuš,
• Jaroslav Kousal,
• Ondřej Kylián,
• Danka Slavínská and
• Hynek Biederman

Beilstein J. Nanotechnol. 2017, 8, 2002–2014, doi:10.3762/bjnano.8.200

• smoothening of the surface. The competition between the two phenomena determines the resultant roughness/smoothness of the film. If deposition is performed onto a sufficiently cold substrate, surface diffusion can be suppressed and roughening will dominate. It has been also recognized that roughening can be

Bi-layer sandwich film for antibacterial catheters

• Gerhard Franz,
• Florian Schamberger,
• Hamideh Heidari Zare,
• Sara Felicitas Bröskamp and
• Dieter Jocham

Beilstein J. Nanotechnol. 2017, 8, 1982–2001, doi:10.3762/bjnano.8.199

• layers were deposited in a water bath (temperature between 70 and 85 °C, mainly at the former value). Analysis Because the roughness of the polymeric substrates does not allow for an exact measurement of the layer thickness and the growth rate as well as the assessment of the morphology, smooth

• : Porosity can be evaluated qualitatively and quantitatively. The qualitative approach comprises visual inspection and scanning of surface areas with atomic force microscopy (AFM). When automatic evaluation procedures are applied, the roughness of the surface can be quantitatively validated. Physical methods

• involve measurement of the impedance of an incompletely isolating layer on top of an electrode. Applying AFM, the small areas of the surface can be scanned and evaluated regarding parameters like roughness and porosity. While the first parameter is the standard output of AFM and is displayed as 3D

Identifying the nature of surface chemical modification for directed self-assembly of block copolymers

• Laura Evangelio,
• Federico Gramazio,
• Matteo Lorenzoni,
• Michaela Gorgoi,
• Francisco Miguel Espinosa,
• Ricardo García,
• Francesc Pérez-Murano and
• Jordi Fraxedas

Beilstein J. Nanotechnol. 2017, 8, 1972–1981, doi:10.3762/bjnano.8.198

• period of the prepattern can be larger than the final period of the self-assembled pattern, and an improvement in both line-edge and line-width roughness. There are mainly two techniques to direct the self-assembly of BCPs: graphoepitaxy and chemical epitaxy. In graphoepitaxy, the BCPs are aligned by a

Imidazolium-based ionic liquids used as additives in the nanolubrication of silicon surfaces

• Patrícia M. Amorim,
• Ana M. Ferraria,
• Rogério Colaço,
• Luís C. Branco and
• Benilde Saramago

Beilstein J. Nanotechnol. 2017, 8, 1961–1971, doi:10.3762/bjnano.8.197

• are silicon wafers b100N with 0.5 mm of thickness and a roughness below 0.1 nm. Stainless steel AISI 316L spheres with 3 mm of diameter were used as counter bodies. Methods Synthesis of ionic liquids [AMIM][Br]: 1-Methylimidazole (14.0 mL, 176 mmol) was dissolved in 50 mL of acetone in a round

Growth and characterization of textured well-faceted ZnO on planar Si(100), planar Si(111), and textured Si(100) substrates for solar cell applications

• Chin-Yi Tsai,
• Jyong-Di Lai,
• Shih-Wei Feng,
• Chien-Jung Huang,
• Chien-Hsun Chen,
• Fann-Wei Yang,
• Hsiang-Chen Wang and
• Li-Wei Tu

Beilstein J. Nanotechnol. 2017, 8, 1939–1945, doi:10.3762/bjnano.8.194

• roughness of the ZnOp(100) sample is sharper than that of the ZnOp(111) sample. In addition, as shown in Table 1, the results of XRD, SEM, and AFM certainly indicate that, for the ZnOp(100) sample, the dominant ZnO(110) grains show ridge-like structures on the surface; for the ZnOp(111) sample, the dominant

• -sized texture of the Si substrate has a limited contribution. Discussion The main grain orientation, surface morphology, AFM surface roughness (Rq) from AFM, average grain size (D), strain (ε), and CL intensity of samples ZnOp(100), ZnOp(111), and ZnOt(100) are shown in Table 1. The results clearly

• wafer surface. The surface roughness of these pyramidal structures was measured as 0.226 µm using AFM. Therefore, the average size of the pyramidal structures was taken to be approximately this value. The pyramidal structures will expose their (111) facets to the wafer surface. However, their physical

Stick–slip boundary friction mode as a second-order phase transition with an inhomogeneous distribution of elastic stress in the contact area

• Iakov A. Lyashenko,
• Vadym N. Borysiuk and
• Valentin L. Popov

Beilstein J. Nanotechnol. 2017, 8, 1889–1896, doi:10.3762/bjnano.8.189

• mode occurs in tribological systems when the thickness of the lubricant layer separating two contacting surfaces is significantly smaller than the typical size of the surface roughness. At such a system configuration, the lateral motion of the friction surface is followed by a contact interaction

(Metallo)porphyrins for potential materials science applications

• Lars Smykalla,
• Carola Mende,
• Michael Fronk,
• Pablo F. Siles,
• Michael Hietschold,
• Georgeta Salvan,
• Dietrich R. T. Zahn,
• Oliver G. Schmidt,
• Tobias Rüffer and
• Heinrich Lang

Beilstein J. Nanotechnol. 2017, 8, 1786–1800, doi:10.3762/bjnano.8.180

• roughness effects. VASE measurements are thus excellently suited to determine the orientation of (metallo)porphyrins in thin films with respect to the substrate surface. Furthermore, the substrate smoothness was shown to have an impact on the orientation of the (metallo)porphyrins with respect to the

• substrates over a period of nine months. A long-term study showed that also the optical spectra of H2TPP(OMe)4 change after ageing in air. Not only the ratio of in-plane to out-of-plane extinction coefficient changes with time, but also the roughness of the samples stored in air increases more rapidly

• leading to an increase of the nominal film thickness (both determined from the ellipsometry data). This could be explained considering that oxygen or moisture from the atmosphere diffuses into the H2TPP(OMe)4 film progressively, with a slight saturation tendency after 20 days. Increasing roughness might