Characterization of 10,12-pentacosadiynoic acid Langmuir–Blodgett monolayers and their use in metal–insulator–metal tunnel devices

• Saumya Sharma,
• Mohamad Khawaja,
• Manoj K. Ram,
• D. Yogi Goswami and
• Elias Stefanakos

Beilstein J. Nanotechnol. 2014, 5, 2240–2247, doi:10.3762/bjnano.5.233

• characteristics for 20 to 30 monolayers of PDA in a Ni–PDA–Ni tunnel junction configuration, with an earlier turn-on voltage for 20 monolayer of PDA compared to that for 30 monolayer of PDA. Conclusion The Langmuir–Blodgett film deposition technique was successfully used to deposit highly conformal and less

Numerical investigation of the effect of substrate surface roughness on the performance of zigzag graphene nanoribbon field effect transistors symmetrically doped with BN

• Majid Sanaeepur,
• Arash Yazdanpanah Goharrizi and
• Mohammad Javad Sharifi

Beilstein J. Nanotechnol. 2014, 5, 1569–1574, doi:10.3762/bjnano.5.168

• impurities, here, we only consider the effect of the substrate material. Any substrate material has some surface roughness (SR). Substrate surface roughness induces a conformal surface roughness on the GNR placed on top of it [27]. It has been shown that SR decreases the mobility of both armchair and zigzag

Review of nanostructured devices for thermoelectric applications

• Giovanni Pennelli

Beilstein J. Nanotechnol. 2014, 5, 1268–1284, doi:10.3762/bjnano.5.141

• ][106][107][108]. Each polymerization step provides a conformal polymer deposition, meanwhile each etching step that follows is anisotropic. Therefore, the etching step removes the polymer on the bottom of the feature while a passivating polymer layer is preserved (or only partially removed) on the

Organic and inorganic–organic thin film structures by molecular layer deposition: A review

• Pia Sundberg and
• Maarit Karppinen

Beilstein J. Nanotechnol. 2014, 5, 1104–1136, doi:10.3762/bjnano.5.123

• free, dense and uniform, but also conformal even when deposited on complex three-dimensional (3D) structures. These features make ALD a method of choice for nanotechnology, for both material synthesis and device fabrication. The technology spectrum in which ALD can be utilized is extremely wide

• the growing film, in which case the GPC is initially lower or higher before settling to a constant value [4]. It is the sequential self-limiting nature of ALD and MLD that enables the great thickness control and conformal growth of the films, which in turn makes the two techniques, ALD and MLD, and

Growth and characterization of CNT–TiO₂ heterostructures

• Yucheng Zhang,
• Ivo Utke,
• Johann Michler,
• Gabriele Ilari,
• Marta D. Rossell and
• Rolf Erni

Beilstein J. Nanotechnol. 2014, 5, 946–955, doi:10.3762/bjnano.5.108

• shown to result in conformal Al2O3 coatings on graphene when using trimethylaluminium and ozone half-cycles, while the use of water resulted in inhomogeneous films [25]. This is due to the generation of oxygenated functional groups on the CNT surface. Also treatments of CNTs prior to ALD by using acids

• such as H3PO4 (together with a chromic acid) and HNO3 triggered conformal growth of ruthenium [26] and SiO2, TiO2, and Al2O3 (after thermal annealing) [27]. Such surface defects seem to be naturally present on multi-wall CNTs with a given surface density. They are responsible for local metal oxide

• nucleation. The density of oxygenated defects can be increased by oxygen plasma treatment. A conformal film is obtained when the nanocrystals coalesce due to lateral growth after approximately 50–100 cycles (depending on the defect density) [28]. Similar results were obtained with Al2O3 coatings by using

DNA origami deposition on native and passivated molybdenum disulfide substrates

• Xiaoning Zhang,
• Masudur Rahman,
• David Neff and
• Michael L. Norton

Beilstein J. Nanotechnol. 2014, 5, 501–506, doi:10.3762/bjnano.5.58

• atomically smooth to enable optimal patterning and imaging through atomic force microscopy (AFM) because the origami structures are very thin and conformal. A final substrate property that needs to be considered for maximal utility is that the material should possess conductive or semiconductive electronic

Atomic layer deposition, a unique method for the preparation of energy conversion devices

• Julien Bachmann

Beilstein J. Nanotechnol. 2014, 5, 245–248, doi:10.3762/bjnano.5.26

• frameworks, is conferred with a direct relevance towards energy conversion applications. The conformal coating of non-planar samples is a property that uniquely defines atomic layer deposition (ALD) [3][4][5][6][7], which is why ALD is inherently suited to the preparation of energy conversion devices. ALD

Modeling and optimization of atomic layer deposition processes on vertically aligned carbon nanotubes

• Nuri Yazdani,
• Vipin Chawla,
• Eve Edwards,
• Vanessa Wood,
• Hyung Gyu Park and
• Ivo Utke

Beilstein J. Nanotechnol. 2014, 5, 234–244, doi:10.3762/bjnano.5.25

• aligned carbon nanotube (VACNT) arrays have emerged as possible scaffolds to support large surface area ceramic layers. However, obtaining conformal and uniform coatings of ceramics on structures with high aspect ratio morphologies is non-trivial, even with atomic layer deposition (ALD). Here we implement

• a diffusion model to investigate the effect of the ALD parameters on coating kinetics and use it to develop a guideline for achieving conformal and uniform thickness coatings throughout the depth of ultra-high aspect ratio structures. We validate the model predictions with experimental data from ALD

• coatings of VACNT arrays. However, the approach can be applied to predict film conformality as a function of depth for any porous topology, including nanopores and nanowire arrays. Keywords: atomic layer deposition; vertically aligned carbon nanotubes; continuum diffusion model; conformal coating

Quantum size effects in TiO₂ thin films grown by atomic layer deposition

• Massimo Tallarida,
• Chittaranjan Das and
• Dieter Schmeisser

Beilstein J. Nanotechnol. 2014, 5, 77–82, doi:10.3762/bjnano.5.7

• by the band gap being too large, has been demonstrated in many systems [3]. Atomic layer deposition (ALD) is a chemical method to grow homogeneous thin films in an atomically controlled mode, which allows for the conformal coating of complex structures with precise thickness and a high degree of

• implementation of efficient photo-electrochemical (PEC) systems is inherently related to the outstanding quality of ALD films, i.e., high purity and homogeneity, and perfect control of thickness in conformal films. It has been shown that very thin films of TiO2 may indeed improve PEC performances [8][9

• ]. Recently, TiO2 nanoparticles (NPs) with an average diameter of 2 nm showed quantum size effects on unoccupied states [10], which involved the hybridization of Ti 3d and Ti 4s orbitals with O 2p orbitals in covalent bonds. The conformal growth of ALD gives the possibility of having homogeneous films below 2

Synthesis of indium oxi-sulfide films by atomic layer deposition: The essential role of plasma enhancement

• Cathy Bugot,
• Nathanaëlle Schneider,
• Daniel Lincot and
• Frédérique Donsanti

Beilstein J. Nanotechnol. 2013, 4, 750–757, doi:10.3762/bjnano.4.85

• ], and 18.2% for (Zn,Sn)O [10]). Recently, our group has synthesized new mixed films of ZnS/In2S3 by using ALD and applied them as buffer layers in CIGS solar cells [11][12]. ALD is based on sequential self-saturated reactions that allows the conformal and uniform growth of thin films with a high control

Evolution of microstructure and related optical properties of ZnO grown by atomic layer deposition

• Adib Abou Chaaya,
• Roman Viter,
• Mikhael Bechelany,
• Zanda Alute,
• Donats Erts,
• Anastasiya Zalesskaya,
• Kristaps Kovalevskis,
• Vincent Rouessac,
• Valentyn Smyntyna and
• Philippe Miele

Beilstein J. Nanotechnol. 2013, 4, 690–698, doi:10.3762/bjnano.4.78

• growth rate calculated from all results is 2.5 Å per cycle. Results of ellipsometric measurements are presented in Table 1. SEM images of ZnO thin films grown by ALD on Si substrates at 200, 500, and 1000 cycles are shown in Figure 1a. The images indicate conformal coating of the Si substrate. A rough

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

• -standing nanoporous oxide membrane. Its mechanical stability is only sufficient for practical purposes if its thickness is beyond 100 µm. Because of the very large aspect ratio of the pores, the ALD SiO2 coating does not reach their lower extremity: in our experimental conditions, the continuous, conformal

Near-field effects and energy transfer in hybrid metal-oxide nanostructures

• Ulrich Herr,
• Balati Kuerbanjiang,
• Cahit Benel,
• Giorgos Papageorgiou,
• Manuel Goncalves,
• Johannes Boneberg,
• Paul Leiderer,
• Paul Ziemann,
• Peter Marek and
• Horst Hahn

Beilstein J. Nanotechnol. 2013, 4, 306–317, doi:10.3762/bjnano.4.34

• aluminium (TMA) and TTIP sources. In both cases, combination with water vapor allows to grow oxides of the respective metal in a layer by layer mode, and achieve a conformal coating of well-defined thickness in this way. The advantage of the ALD process is that this conformal coating can be achieved without

Ordered arrays of nanoporous gold nanoparticles

• Dong Wang,
• Ran Ji,
• Arne Albrecht and
• Peter Schaaf

Beilstein J. Nanotechnol. 2012, 3, 651–657, doi:10.3762/bjnano.3.74

• , 85748 Garching, Germany Center for Micro- and Nanotechnologies, Ilmenau University of Technology, POB 10 05 65, 98684 Ilmenau, Germany 10.3762/bjnano.3.74 Abstract A combination of a “top-down” approach (substrate-conformal imprint lithography) and two “bottom-up” approaches (dewetting and dealloying

• by using laser interference lithography [15], focused ion beam (FIB) [17], or substrate conformal imprint lithography (SCIL) [19]. During the dewetting of metal films onto prepatterned substrates, the periodic structure of the prepatterned substrates modulates the local excess chemical potential by

Approaches to nanostructure control and functionalizations of polymer@silica hybrid nanograss generated by biomimetic silica mineralization on a self-assembled polyamine layer

• Jian-Jun Yuan and
• Ren-Hua Jin

Beilstein J. Nanotechnol. 2011, 2, 760–773, doi:10.3762/bjnano.2.84

• essential for practical device fabrication that biomimetic nanostructured silica materials can be directly generated on the surface of various substrates [19]. One method is to chemically bond, or physically adsorb, long-chain amines or proteins on the substrates, in order to form the conformal molecular

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

• substrate conformal imprint lithography (SCIL) [37] and investigated by scanning electron microscopy (SEM): One with a square array of pyramidal pits (substrate type A), shown in Figure 1a, and another with an array of circular holes with square symmetry (substrate type B), shown in Figure 1b. The pits in

• , and result in the formation of precise 2D particle arrays via dewetting. In addition, the substrate conformal imprint lithography (SCIL) technique enables the production of large areas of pre-patterned substrates with high uniformity and the corresponding fabrication of large areas of ordered 2D

• square array of pyramidal pits (substrate type A), shown in Figure 1a, and an array of circular holes with square symmetry (substrate type B), shown in Figure 1b, by employing the substrate conformal imprint lithography (SCIL) and reactive ion etching (RIE, Oxford Plasmalab 100 and STS 320 PC). The SCIL