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DNA origami method aims at the construction of nanometer sized bio-templates from a long single-stranded DNA molecule [1,2]. It allows to build a variety of different structures and functionalities arranged with a resolution of about 1 nm for devices like plasmonic antennas or optical waveguides [3]. Our contribution deals with the immobilization of DNA origami templates in well-defined micrometer structures on 6-inch silicon wafers aiming a large-scale fabrication. We present a process of surface structuring of hydrophobic diamond-like carbon and fluorocarbon-polymer layers onto hydrophilic SiO2. Further we introduce a procedure for selective DNA Origamis self-immobilization in these hydrophilic cavities.

Technologies for 3D-Wafer Level Packing (WLP) of Micro electro Mechanical Systems (MEMS) are described with respect to devices that find applications in thin packages (e.g. smart cards). An aspired final device thickness in the range of 350EL400 µm is achieved by using Cu based Through Silicon Vias (TSV's) Wafer Level Bonding (WLB) wafer thinning. In particular, two Via Last approaches using TSV's in the cap wafer and device wafer, respectively, are described. According to this, two WLB technologies are investigated: glass frit bonding as well as Silicon Direct Bonding (SDB) of Si-SiO2. The first technique has been demonstrated using a MEMS accelerometer including electrical tests and cross sectional analysis.

Ziel der elektrochemischen Abscheidung (ECD) von Aluminium (Al) und Palladium (Pd) aus ionischen Flüssigkeiten ist die Herstellung von nanoskaligen reaktiven Materialsystemen (RMS) für ein Waferbondverfahren bei Raumtemperatur. Das Schichtsystem Al/Pd ist ein hochenergetisches System, welches nach Initiierung chemisch exotherm miteinander reagiert. Durch die schnelle Reaktion erfolgt eine lokale Erhitzung, wodurch ein Fügeprozess möglich ist. Derzeit werden die RMS in einem alternierenden Sputterprozess (Kathodenzerstäubung) hergestellt, wobei die Abscheidung auf mehreren Substraten gleichzeitig große Anforderungen an die Anlagentechnik stellt.

The determination of built-in strain in semiconductor devices with nanometer spatial resolution and high sensitivity is needed for the characterization of nanoscale electronic devices. Kelvin probe force microscopy (KPFM) is an atomic force microscopy-based method that provides the spatially resolved surface potential at the sample surface, fulfilling the requirements on resolution and sensitivity. The contrast observed in KPFM imaging is often attributed to stress, but there are only a few reports on the application of KPFM for quantitative stress analysis [1]. In this contribution we focus on the application of KPFM for analysis of stress in silicon devices, such as copper through silicon vias and silicon membranes. The experimental results are compared with density functional theory calculations of strained silicon. This work provides critical insights into the quantitative determination of stress at the nanoscale that so far has gone largely unnoticed in the scanning probe microscopy community. [1] W. Li, D.Y. Li, J. Appl. Phys. 99, 073502 (2006).

Direct synthesis of poly (sodium 4-styrenesulfonate) (P(NaSS)) inside the channel of single-walled carbon nanotube (SWCNT) field-effect transistors (FETs), is shown to be highly beneficial in improving the device parameters. Starting with monomeric compounds, the FET-channel was in-situ polymerized, using the self-initiated photografting and photopolymerization process. Upon formation of the P(NaSS) polymer matrix, we report improved device-to-device consistency, lower variability in the threshold voltage, higher drain currents and higher on/off ratios. Annealing in vacuum was shown to further improve the device performance and induce an ambipolar behavior. Moreover, those FET devices showed a long-term stability even under ambient environment.

For an industrial realization of devices based on single-walled carbon nanotube (SWCNTs) such as field-effect transistors (FETs) it becomes increasingly important to consider technological aspects such as intrinsic device structure, integration process controllability as well as yield. From the perspective of a wafer-level integration technology, the influence of SWCNT length on the performance of short-channel CNT-FETs is demonstrated by means of a statistical and comparative study. Therefore, a methodological development of a length separation process based on size-exclusion chromatography was conducted in order to extract well-separated SWCNT dispersions with narrowed length distribution. It could be shown that short SWCNTs adversely affect integrability and reproducibility, underlined by a 25% decline of the integration yield with respect to long SWCNTs. Furthermore, it turns out that the significant changes in electrical performance are directly linked to a SWCNT chain formation in the transist.

The growth of ultrathin (

The synthesis of compounds [Mn(i5-C5H4SiMe3)(CO)3] (1), [Mn(i5-C5H3-1-SiMe3-3-Me)(CO)3] (2), [Mn(i5-C5H4tBu)(CO)3] (3), [Mn(i5-C5Me5)(CO)3] (4) and [Mn(i5-C5H7)(CO)3] (5) and their potential use as metal-organic chemical vapor deposition (MOCVD) precursors for the deposition of manganese-based layers is reported. The thermal behavior of 1-5 was studied by thermogravimetry showing that these compounds evaporate in the temperature range of 363-498 K depending on the cyclopentadienyl substituents and the type of pentadienyl used. Vapor pressure measurements indicate that all compounds possess vapor pressures between 60 and 630 Pa at 353 K. Compounds 1-5 could be successfully applied in manganese-based film deposition without activation steps prior to the MOCVD experiments. The as-deposited thin layers were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy and X-ray powder diffraction. Under comparatively mild conditions, whereas 5 possesses the lowest deposition temperature (553 K), dense and conformal layers with growth rates up to 7.0 nm min− 1 (5) could be deposited. Metal carbonyls 1 and 2 featuring a SiMe3 group produced Si-containing manganese-based films. The as-deposited layers from 1, 2, 4 and 5 contain carbon impurities (5-8.9 mol-%), while the films from 3 are carbon-free. The layers from 1 and 2 consist of mainly manganese silicate and manganese oxide, whereas those obtained from 3 to 5 are composed of manganese oxides.

Microelectromechanical system (MEMS) actuators essentially have movable silicon structures where the mechanical motion can be activated electronically. The microscanner is one of the most successfully commercialized MEMS devices which are widely used for collecting optical information, manipulating light, and displaying images. While silicon is abundant, it is also brittle and stiff and when microprocessed, defects are not uncommon. These defects result in weakness under torsional stress and this has been the key factor limiting the scanning performance of the microscanner. Here a metallic glass (MG)-based microscanner is reported with MG as the material for the moving torsion bars. The low elastic modulus, high fracture toughness, and high strength of MG offers, for the first time, an ultralarge rotating angle of 146 degrees with power consumption lowered to the microwatt range, and a smaller driving force and better actuation performance, than conventional single crystal silicon and polycrystalline silicon. The high spatial resolution and large scanning field of the MG-based microscanner are demonstrated in the tomographic imaging of a human finger. This development of an MG-based MEMS possibly opens a new field of low-powered MEMS devices with extreme actuation and enhanced sensing.

We report about a detailed comparison of the additive manufacturing methods inkjet printing (IJP) and aerosol jet printing (AJP). Both technologies are based on the direct-writing approach enabling the non-contact deposition of various materials in flexible patterns, e.g., for printed electronic applications. The deposited pattern elements were classified as (i) drops (IJP) or splats (AJP), (ii) lines, and (iii) squares. These elements can be considered as basic elements of the deposition systems and also of printed electronics. The pattern elements were deposited with IJP and AJP using the same silver nanoparticle ink. After printing, the layers were characterized regarding their morphology by optical and topographical measurement methods as well as regarding their electrical characteristics. It turned out that drops deposited with IJP and splats deposited with AJP can have similar dimensions. However, the shapes of the deposits differ widely. In the case of lines, AJP enables narrower line widths and thinner line thicknesses in comparison to IJP. In IJP, the line morphology varies depending on the direction of the deposition. Finally, the morphology of the deposited lines determines the electrical conductivity. For printed squares, the IJP layers show much higher layer thickness and a different layer topography compared with AJP as result of a higher volume per area deposition of materials.

Organic semiconductors have potential applications in the spintronics field due to the weak spin scattering mechanism in organic molecules, which implies that the spin polarization of the carriers can be maintained for a much longer time (in the range µs to ms) than in inorganic materials. Cost-efficient, wafer level fabrication of such devices is one of the main challenges in this field. Currently e-beam lithography is used for fabricating the required small electrode gap dimensions. Previously, we reported an alternative approach for fabricating laterally stacked organic trench devices using conventional optical lithography, where paramagnetic (CoPc, CuPc) and diamagnetic Alq3 molecules were evaporated to form the organic channels. It was observed that the molecules form a membrane between the electrodes. In this work, solution processing of organic materials was tested by drop-coating of water-soluble 3,4',4",4‴-copper(II) phthalocyanine-tetrasulfonic acid tetrasodium salt (TSCuPc). Using this approach it was possible to fill the trenches. A comparative study of a solution processed device and a device with evaporated channel material is presented.

Active Flow Control (AFC) devices in rotor blades offer a high potential to improve the efficiency of wind turbines, e.g., by increasing rotor blade lift, improving load control or reducing acoustic emission. Thus, the energy yield can be increased and/or the rotor blades be downsized - both implying positive economic consequences. However, since AFC devices also cause additional costs in different phases of their life cycle, a life cycle-related evaluation of their profitability is necessary. The paper presents a decision theory-based procedure model, which enables not only a sophisticated evaluation of AFC concepts and devices but also the identification of needs and potentials for improvement.

Atomistic mechanisms for the atomic layer deposition using the Cu(acac)(2) (acac = acetylacetonate) precursor are studied using first-principles calculations and reactive molecular dynamics simulations. The results show that Cu(acac)(2) chemisorbs on the hollow site of the Cu(110) surface and decomposes easily into a Cu atom and the acac-ligands. A sequential dissociation and reduction of the Cu precursor [Cu(acac)(2) -> Cu(acac) -> Cu] are observed. Further decomposition of the acac-ligand is unfavorable on the Cu surface. Thus additional adsorption of the precursors may be blocked by adsorbed ligands. Molecular hydrogen is found to be nonreactive towards Cu(acac)(2) on Cu(110), whereas individual H atoms easily lead to bond breaking in the Cu precursor upon impact, and thus release the surface ligands into the gas-phase. On the other hand, water reacts with Cu(acac)(2) on a Cu2O substrate through a ligand-exchange reaction, which produces gaseous H(acac) and surface OH species. Combustion reactions with the main by-products CO2 and H2O are observed during the reaction between Cu(acac)(2) and ozone on the CuO surface. The reactivity of different co-reactants toward Cu(acac)(2) follows the order H > O-3 > H2O.

Silver(I) dithiocarbamates [Ag{S2CNR(C2H4OH)}] (3a, R = Me; 3b, R = Bu) were accessible by the reaction of AgNO3 with K{S2CNR(C2H4OH)} (2a, R = Me; 2b, R = Bu). Alternatively, 3b could be prepared by the condensation of CS2 and Ag2O with NHBu(C2H4OH) (1b). The thermal behavior of 3 was studied by thermogravimetric (TG) analysis. A two-step decomposition process leads to the formation of a-Ag2S, as evidenced by X-ray powder diffraction studies. A decomposition mechanism of 3a to form Ag2S through the release of 3-methyloxazolidine-2-thione is discussed based on TG-MS, GC-MS, and NMR experiments. Because of the better solubility of 3b, this complex was tested for Ag2S spin-coating deposition studies on different substrates (SiO2/Si, TiN/SiO2/Si, glass) with subsequent annealing at 450 °C under a N2 atmosphere. Film thickness, composition, and morphology of the as-deposited films were determined by XRD, SEM, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy, which showed the formation of 200 nm thick, conformal, adherent, monoclinic a-Ag2S layers.

Mask less fabricated 3D interconnects may have a big potential in future microelectronic applications by enhancing freedom of device design or power- and footprint saving capabilities along with performance improvements. Within this paper research activities are reported about evaluation of Aerosol Jet Printing (AJP) for feasibility of fabricating non-planar nano particle based electrical chip interconnects on a 3D-integrated System in a Package (SiP) including MEMS that is capable to wake up integrated electronics from power down mode using piezoelectric MEMS components. 3D-stacked multi-chip modules with a footprint of 9 mm x 10 mm are functional connected by AJP after single chips are mounted to printed circuit board (PCB) using underfiller adhesives. AJP, morphology of printed paths, and electrical resistances are investigated. Several challenging factors like printed line width, printed layer thickness, focus limiting standoff height of printhead, thermo-mechanical properties of printed interconnects along with SiP layout were identified and discussed during process development.

Organic semiconductors are considered as attractive materials for spintronic applications. One of the current challenges in this field resides in the cost-effective fabrication of devices with laterally stacked electrodes and their integration at the wafer level. In this work lateral devices with electrodes separated by sub-100 nm gaps were fabricated using conventional UV lithography combined with semiconductor processing. Following a metallization step for the preparation of Au or Co electrodes, organic films were evaporated in high vacuum. Typically an average film thickness of 350 nm was required to form a nanomembrane that closes the gap between the electrodes. These structures allow the systematic investigation of electric and magnetoresistive properties of diamagnetic and paramagnetic organic semiconductor materials (in this case Alq3 and cobalt phthalocyanine) as a function of the width of the electrode gap. These devices are intended to be used in magnetoresistive devices and molecular spintronics.

The paper shows the potential of micro machined sensors for implantation and monitoring of patients. Next to well known sensors it is focused on inertial sensors and a way for further miniaturization keeping the performance and accuracy of the sensor. Furthermore the ongoing investigation of materials used for MEMS packaging and MEMS fabrication will be described. Here, special encapsulation techniques should show a miniaturization potential realized by the substitution of thick medical packages like Titanium housings.

In this work we describe the bonding and contacting of a micro machined vertically integrated 3-D micro scanner, which is a key-component for a number of scanning imaging micro systems, such as confocal microscopes on-chip or optical coherence tomography (OCT) probes for micro endoscopy. The 3-D micro scanner is composed of two electrostatic silicon MEMS micro actuators which are vertically aligned and bonded with glass and ceramic components to create hermetically sealed cavity for scanning micro lenses. In addition, the through wafer vias (TWV) technology is employed to establish electrical connection from the top to the bottom through a stack of two SOI wafers, one glass wafer and one ceramic wafer. Presented methods are of general importance for various silicon-based vertically integrated devices.

Carbon nanotube (CNT) based interconnects with an improved bottom metallization scheme were prepared and characterized. Two procedures are introduced to enhance the CNT via performance after planarization. Both, temperature annealing of the metal-CNT contact and exposing the CNT tips to HF vapor prior to the deposition of the top metallization increased the yield and reduced the resistance of the vias. For a via of 5 µm diameter and a depth of 800 nm a resistance of 8 ohm was obtained. Further, the resistance of individual CNTs was measured by means of conductive atomic force microscopy (cAFM), giving a value of 38 kohm/CNT. We highlight the capability of cAFM to accurately predict the overall electrical performance of CNT based vias. Deviations of the measured resistance compared to the theoretical limit are either attributed to defects in the CNT's atomic structure or imperfect contacts. To separate those two aspects, different methods to investigate the microstructure of the employed materials were used.

We study quasi-ballistic electron transport in metallic $(6,0)$ carbon nanotubes (CNTs) of variable length in contact with Al, Cu, Pd, Pt, Ag, and Au electrodes by using the non-equilibrium Green's function formalism in combination with either density functional theory or self-consistent extended Hückel theory. We find good agreement between both. Visualizing the local device density of states of the systems gives a descriptive link between electronic structure and transport properties. In comparison with bare finite and infinite tubes, we show that the electronic structure of short metallic CNTs is strongly modified by the presence of the metallic electrodes, which leads to pronounced size effects in the conductance. The mean conductances and linear response currents allow a ranking of the metals regarding their ability to form low-Ohmic contacts with the nanotube: ${\rm Ag}\lesssim {\rm Au}\lt {\rm Cu}\ll {\rm Pt}\approx {\rm Pd}\ll {\rm Al}$. These findings are contrasted with similar trends in contact distance, binding energy, calculated work function of the metal surfaces, and various results from literature.

Exothermic self-propagating high-temperature synthesis of intermetallic compounds attain increasing interest in the field of wafer bonding in microelectronics and microsystems technology due to local heat generation. Numerical models of self-sustaining reactions in thin multilayer films can be used to predict velocity and shape of the reaction front. This work deals with heat losses to various substrate materials and material compounds used for wafer bonding as well as the prediction of minimal numbers of bilayers required for a self-propagating reaction front. We introduced a cylindrically symmetric finite element approach. In addition to that, the effect of temperature-dependent specific heat capacities was investigated. Numerical computations were performed for Pd/Al multilayers and are compared to experimental data. It was found that the developed formalism is suitable to determine the mutual influence of heat losses and reaction properties. Furthermore, it was demonstrated that minimal numbers of bilayers can be determined more precisely by including temperature-dependent specific heat capacities.

This paper reports on the ohmic contacts of an radio-frequency micro-electro-mechanical-system (RF MEMS) switch. The structure of the MEMS is described briefly to give information about the organization of the switch device. The most significant performance data are reported, indicating very low actuation voltage below 5 V, switching time of