This work has been devoted to the study of phase transformations involving chemical ordering and magnetic properties evolution in bulk Fe-Pt alloys composed of nanometer-sized grains. A comprehensive study of phase transformations and ordering in Fe-Pt alloys is performed by a combination of in-situ neutron powder diffraction and thermal analysis. The dependence of ordering processes on the alloy composition and initial microstructure (homogeneous A1 phase or multilayer-type) is established. Through the use of mechanical alloying and subsequent heat treatment it has been possible to achieve the formation of chemically highly ordered L10 FePt and, in the case of the Fe-rich and Pt-rich compositions, L12 Fe3Pt and FePt3 phases, respectively. Whereas in Pt-rich alloys the decoupling effect of the FePt3 phase leads to coercivity improvement, in Fe-rich nanocomposites a peculiar nanometer scale multilayer structure gives rise to remanence enhancement due to large effects of exchange interactions between the crystallites of the phases. The structure, magnetic properties and magnetisation reversal processes of these alloys are investigated. Experimentally observed phenomena are understood on the basis of a simple two-particle interaction model. Neutron diffraction has also been used for the investigation of the magnetic structure of ordered and partially ordered nanocrystalline Fe-Pt alloys. It has been shown that the magnetic moment of Fe atoms in L10-type Fe Pt alloys is sensitive to the compositional order. The results are compared to density functional calculations.

L’ablation de cibles d’Al nanocristallines (taille moyenne des cristallites d = 3,1 et 6,2 nm) par impulsions laser ultrabrèves (200 fs) a été étudiée par l’entremise de si- mulations combinant la dynamique moléculaire et le modèle à deux températures (two- temperature model, TTM) pour des fluences absorbées allant de 100 à 1300 J/m2. Nos simulations emploient un potentiel d’interaction de type EAM et les propriétés électro- niques des cibles en lien avec le TTM sont représentées par un modèle réaliste possédant une forme distincte dans le solide monocristallin, le solide nanocristallin et le liquide. Nous avons considéré l’effet de la taille moyenne des cristallites de même que celui de la porosité et nous avons procédé à une comparaison directe avec des cibles mono- cristallines. Nous avons pu montrer que le seuil d’ablation des métaux nanocristallins est significativement plus bas, se situant à 400 J/m2 plutôt qu’à 600 J/m2 dans le cas des cibles monocristallines, l’écart étant principalement dû à l’onde mécanique plus im- portante présente lors de l’ablation. Leur seuil de spallation de la face arrière est aussi significativement plus bas de par la résistance à la tension plus faible (5,40 GPa contre 7,24 GPa) des cibles nanocristallines. Il est aussi apparu que les contraintes résiduelles accompagnant généralement l’ablation laser sont absentes lors de l’ablation de cibles d’aluminium nanocristallines puisque la croissance cristalline leur permet d’abaisser leur volume spécifique. Nos résultats indiquent aussi que le seuil de fusion des cibles nano- cristallines est réduit de façon marquée dans ces cibles ce qui s’explique par la plus faible énergie de cohésion inhérente à ces matériaux. Nos simulations permettent de montrer que les propriétés structurelles et électroniques propres aux métaux nanocristallins ont toutes deux un impact important sur l’ablation. / The ablation of nanocrystalline (mean crystallite size d = 3.1 and 6.2 nm) Al tar- gets by ultrashort (200 fs) laser pulses was studied using hybrid simulations combining molecular-dynamics and the two-temperature model (TTM) for a range of absorbed flu- ence of 100 to 1300 J/m2. Our simulations employ an EAM interatomic potential and the TTM-related electronic properties are modelled using three distinct functions to rep- resent the monocrystalline solid, the nanocrystalline solid, and the liquid in an accurate way. Comparison between targets displaying two mean grain sizes, porous targets, and monocrystalline targets are reported. This study showed a significantly reduced abla- tion threshold of 400 J/m2 instead of the 600 J/m2 obtained for the single crystals, the discrepancy being mainly accounted for by an increase in the magnitude of the pressure wave generated during ablation. The spallation threshold of the back side of the target is also reduced owing to a lower tensile strength (5.40 GPa against 7.24 GPa). This work also allowed to discover that residual stress generally associated with laser ablation is totally absent in nanocrystalline samples as crystal growth provides a mechanism for volume reduction near the melting temperature. Furthermore, our results demonstrate that the melting threshold shows an important decrease and the melting depth an im- portant increase in the nanocrystalline samples which can be explained by their lower cohesion energy. Our simulations shed light on the fact that a realistic modelling of both structural and electronic properties of the nanocrystalline target is important to produce a reliable representation of laser ablation.

The continuous microreactor-assisted solution deposition (MASD) process was used for the deposition of CdS thin films on fluorine-doped tin oxide (FTO) glass. The MASD system, including a T-junction micromixer and a microchannel heat exchanger is capable of isolating the homogeneous particle precipitation from the heterogeneous surface reaction. The results show a dense nanocrystallite CdS thin films with a preferred orientation at (111) plane. Focused-ion-beam was used for TEM specimen preparation to characterize the interfacial microstructure of CdS and FTO layers. The band gap of the microreactor-assisted deposited CdS film was determined at 2.44 eV. X-ray Photon Spectroscopy show the bindings of energies of Cd 3d₃/₂, Cd 3d₅/₂, S 2p₃/₂ and S 2p₁/₂ at 411.7 eV, 404.8 eV, 162.1 eV, and 163.4 eV, respectively. The film growth kinetics was studied by measuring the film thickness deposited from 1 minute to 15 minutes in physical (FIB-TEM) and optical (reflectance spectroscopy) approaches. A growth model that accounts for the residence time in the microchannel using empirical factor (η) obtained from previous reported experimental data. Applying this factor in the proposed modified growth model gives a surface reaction rate of 1.61*10⁶ cm⁴ mole⁻¹s⁻¹, which is considerable higher than the surface reaction rates obtained from the batch CBD process. With the feature of separating homogeneous and heterogeneous surface reaction, the MASD process provides the capability to tailor the surface film growth rate and avoid the saturation growth regime in the batch process. An in situ spectroscopy technique was used to measure the UV-Vis absorption spectra of CdS nanoparticles formed within the continuous flow microreactor. The spectra were analyzed by fitting the sum of three Gaussian functions and one exponential function in order to calculate the nanoparticle size. This deconvolution analysis shows the formation of CdS nanoparticles range from 1.13 nm to 1.26 nm using a residence time from 0.26 s to 3.96 s. Barrier controlled coalescence mechanism seems to be a reasonable model to explain the experimental UV-Vis data obtained from the continuous flow microreactor, with a rate constant k' value of 2.872 s⁻¹. Using CFD, low skewness value of the RTD curve at high flow rate (short τ) suggests good radial mixing at high flow rate is responsible for the formation of smaller CdS nanoparticles with a narrower size distribution. The combination of CdS nanoparticle solution with MASD process resulted in the hindrance of CdS thin film deposition. It is hypothesized that the pre-existing sulfide (S²⁻) ions and CdS nanoparticles changes the chemical species equilibrium of thiourea hydrolysis reaction. Consequently, the lack of thiourea slows down the heterogeneous surface reaction. To test the scalability of the MASD process, a flow cell and reel-to-reel (R2R)-MASD system were setup and demonstrated for the deposition of CdS films on the FTO glass (6" x 6") substrate. The film deposition kinetics was found to be sensitive to the flow conditions within the heat exchanger and the substrate flow cell. The growth kinetics of the CdS films deposited by R2R-MASD process was investigated by with a deposition time of 2.5 min, 6.3 min, and 9 min. In comparison with the continuous MASD process, the growth rate in R2R-MASD is higher, however more difficult to obtain a linear relationship with the deposition time. / Graduation date: 2012 / Access restricted to the OSU Community at author's request from Jan. 13, 2012 - Jan. 13, 2013

Made available in DSpace on 2016-12-08T15:56:18Z (GMT). No. of bitstreams: 1 KATIUSCA WESSLER MIRANDA.pdf: 4397696 bytes, checksum: da27bc7c1adc7efa3e74ecfcf87feb0e (MD5) Previous issue date: 2015-08-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This paper studied ring opening polymerizations L-lactide (LLA) and ε-caprolactone (ε-CL) by bulk polymerization and solution polymerization, in order to evaluate the influence of initiator concentration, reaction time and reaction temperature on the yield and molecular weight of both polymers. Tin octoate and methanol was employed as initiators. It was observed that LLA and ε-CL speed ring opening polymerization, increases with temperature and that the monomer/polymer conversion immediately occurs in the first hours of synthesis when 2% of initiator is used. The molar mass, determined by capillary viscometry, was approximately 7x103 g/mol, for both polymers. It was also studied the copolymerization of LLA and ε-CL by solution polymerization employing different solvents. Weight percentages of LLA/ε-CL equal to 100/0, 95/5, 90/10, 85/15 and 80/20 were studied. The toluene was the only solvent that enabled the production of polymers and copolymers at 120 ° C. Initiator concentration equal to 0.015% and reaction time equal to 24 hours, were assessed, generating polymers with average molar mass (Mw) around 2x104 g / mol, determined by GPC. It was observed by proton and carbon 13 nuclear magnetic resonance (13 C-NMR and 1H-NMR) that reactions conducted with ε-CL concentrations lower than 15% do not yield copolymer, only PLLA. Bulk polymerization it was also studied and the main difference compared to solution polymerization is associated with the molar mass of the copolymer P(LLA-co-εCL)80/20. This product had a higher molar mass when synthesized by the first technique. After the study of copolymerization, the functionalization of nanocrystalline cellulose particles (CNC) with LLA and ε-CL, by polymerization in solution, was studied. Three compositions were analyzed: (i) PLLA-CNC, (II) P(LLA-co-εCL)85/15-CNC and (III) P(LLA-co εCL)80/20-CNC; the reactions were conducted at 120 ° C for 24 hours. It was possible to functionalize CNC particles in situ, using 80/20 LLA/ε-CL systems, with tin octoate (0.015 wt%) as catalyst and toluene as solvent (composition III). The functionalization was confirmed by Fourier transform infrared spectroscopy (FTIR). The compatibility of the P(LLA-co-εCL)80/20-CNC particle increased in toluene, confirming the reduction of hydrophilicity of these particles. Unlike occurred with the compositions (I) and (II), the composition (III) only allowed the production CNC functionalized particles. PLLA, PCL and / or P (LLA-co-εCL) were not produced. This fact indicates that the concentration of ε-CL and the presence of cellulose hydroxyl groups decreased the reactivity between the monomers. / Neste trabalho foram estudadas as reações de abertura de anel dos monômeros L-lactídeo (LLA) e ε-caprolactona (ε-CL), pela técnica de polimerização em massa com o intuito de avaliar a influência da concentração de iniciador, do tempo e da temperatura de reação sobre o rendimento reacional e a massa molar de ambos os polímeros. O iniciador empregado neste estudo foi o octoato de estanho e como co-iniciador, metanol foi empregado. Foi observado que a velocidade de reação de obtenção do poli(L-ácido láctico) (PLLA) e da poli(ε-caprolactona) (PCL) aumenta em função da temperatura e que com 2% de iniciador a conversão de monômero em polímero ocorre logo nas primeiras horas de síntese. A massa molar determinada por viscosimetria capilar foi de aproximadamente 7x103 g/mol para ambos os polímeros. Também foi estudada a obtenção de copolímeros de LLA e ε-CL por reações de polimerização em solução empregando diferentes solventes. As porcentagens mássicas de LLA/ε-CL empregadas foram 100/0, 95/5, 90/10, 85/15 e 80/20. O tolueno foi o único solvente que possibilitou a produção de polímeros e copolímeros a 120 °C. Para estas sínteses a concentração de iniciador foi igual a 0,015% e o tempo de reação foi de 24 horas, gerando polímeros com massa molar ponderal média (Mw) ao redor de 2x104 g/mol, determinadas por GPC. Foi observado por ressonância magnética nuclear de hidrogênio e de carbono 13 (RMN1H e RMN13C) que as reações conduzidas com concentrações de ε-CL inferiores à 15% não rendem copolímero, apenas PLLA é produzido. A obtenção de copolímeros pela técnica de polimerização em massa também foi estudada e a principal diferença em relação a polimerização em solução está associada à massa molar do copolímero P(LLA-co-εCL)80/20, sendo que o produto da polimerização em massa apresentou massa molar mais elevada que o obtido pela polimerização em solução. Após o estudo da obtenção dos copolímeros, foi estudada a funcionalização de partículas de celulose nanocristalina (CNC) com os monômeros de LLA e ε-CL pela técnica de polimerização em solução. Foram analisadas três composições: (I) PLLA-CNC, (II) P(LLA-co-εCL)85/15-CNC e (III) P(LLA-co-εCL)80/20-CNC; as reações foram conduzidas a 120°C durante 24 horas. Foi possível funcionalizar partículas de CNC in situ, empregando 80% de LLA, 20% de ε-CL, 0,015% de octoato de estanho e tolueno como solvente (composição III). A funcionalização foi confirmada por análises de espectroscopia de infravermelho por transformada de Fourier (FTIR). Testes de dispersão do P(LLA-co-εCL)80/20-CNC em tolueno confirmaram a diminuição da hidrofilicidade destas partículas. Ao contrário do ocorrido com as composições (I) e (II), a composição (III) permitiu somente a produção partículas de CNC funcionalizadas. PLLA, PCL e/ou P(LLA-co-εCL) não foram produzidos. Este fato indica que o aumento da concentração de ε-CL e a presença de grupos hidroxilas de celulose diminuíram a reatividade entre os monômeros.

La thèse s'inscrit dans le cadre du projet GENOME « Gestion Optimisée de l'Energie » dont l'enjeu majeur est la conception d'un avion plus électrique. L'augmentation de l'efficacité énergétique et de la compacité des systèmes électriques de ces avions entraîne de fortes sollicitations en température. Ces sollicitations sont liées à la compacité des systèmes (réduction de masse et de volume) ainsi qu'à leur localisation par rapport aux sources chaudes (réacteur d'avion par exemple). De ce fait, les matériaux magnétiques des nouveaux convertisseurs électriques doivent pouvoir fonctionner sous des conditions de hautes températures, supérieures à 200°C. Il s'agit du polycristallin FeCoV dédié à la fabrication des tôles du stator et du rotor des génératrices rapides (situées à proximité des réacteurs) et le nanocristallin FeCuNuSiB dédié à la conception des inductances et transformateurs des convertisseurs statiques. Ce manuscrit s'intéresse à l'étude du vieillissement thermique de ces deux familles de matériaux magnétiques. Ces matériaux, fournis par la société APERAM, se déclinent sous plusieurs nuances et finitions. L'étude du vieillissement consiste en l'application de plusieurs essais de vieillissement continus sous différentes températures (jusqu'à 300 °C pour les FeCoV et 240 °C pour les nanocristallins). Plusieurs grandeurs macroscopiques magnétiques, électriques et mécaniques (pour les FeCoV) sont mesurées à chaque intervalle de vieillissement. Grâce à ces mesures macroscopiques et à des mesures complémentaires effectuées à l'échelle microscopique, des analyses sont faites et des hypothèses sont proposées afin d'expliquer les mécanismes de vieillissement de ces deux familles de matériaux et dans le but de proposer des modèles phénoménologiques fiables / The thesis takes part of the project GENOME “Gestion Optimisée de l’Energie” whose major issue is the design of the more electrical aircraft. The increase in the energy efficiency and the compactness of the electrical systems of these aircrafts lead to high temperature stresses. These thermal stresses are related to the compactness of the systems (reduction of mass and volume) as well as their location with respect to the hot sources (aircraft engine for example). Thus, the magnetic materials of the new electrical converters must be able to operate under conditions of high temperatures, above 200 °C. Typically, the FeCoV polycrystalline materials are dedicated to the fabrication of the stator and rotor sheets of the fast generators (located near the aircraft engine) and the FeCuNbSiB nanocrystalline materials are dedicated to the design of inductors and transformers of the static converters.This manuscript concerns the thermal ageing study of these two magnetic material families. These materials, supplied by the company APERAM, are available in several shades. The ageing study consists on applying several continuous ageing treatments at different temperatures (up to 300 °C for FeCoV and 240 °C for FeCuNbSiB). At each ageing step, several macroscopic properties namely: magnetic, electrical and mechanical (for the FeCoV materials) properties are measured. Using these macroscopic properties and complementary measurements carried out on a microscopic scale, analyses are made and hypotheses are proposed in order to explain the ageing mechanisms of these magnetic material families. The understanding of the magnetic ageing mechanisms is necessary towards establishing of phenomenological ageing models

The development of radio frequency integrated circuits (RFICs), especially the dream of integrating analog, digital and radio frequency (RF) components on the same chip that is commonly known as System-on-a-Chip (SoC), is crucial to mobile communications of the future. Such SoC approach offers enhanced performance, greater reliability, and substantially less power consumption of integrated circuits while reducing overall physical size and thus manufacturing cost. However, the progress has been stalled by the lack of miniaturized inductor elements. Rise of unwanted parasitic effects limits down-scaling of the inductor structures and leaves the use of magnetic coating as a viable and attractive option to enhance the inductance and thus inductance density. It is also essential to shift from perm alloy and other amorphous alloys to ferrites and hex ferrites as the core material because of their very high electrical resistivity so as to keep losses in check, a criterion that cannot be compromised on in GHz frequency applications. This is viable, however, only if the integration of the magnetic core (film), particularly a ferrite film, is fully compatible with the CMOS fabrication process. Various approaches have been taken to meet this requirement, including investigations of employing layers of ferrite materials to envelop the inductor loop. However, the deposition of thin films of ferrites, whether by PVD or CVD, usually calls for the deposited ferrite layer to be annealed at an elevated temperature to crystallize the layer so that its magnetic characteristics are appropriate for the optimum performance of the circuit element. Such annealing is incompatible with CMOS process flow required for aggressive device geometries, as the inductor element is added after the active semiconductor circuit is processed, and any exposure of the processed circuit to elevated temperatures risks disturbing precise doping profiles employed and the integrity of the inter-layer dielectrics. What is called for is a low-temperature process for the deposition of a ferrite layer on top of the patterned inductor element – a layer of thickness such that most of the fringe field is encapsulated – while ensuring that the layer comprises crystallites of uniform size that leads to uniform magnetic behaviour. Recognizing the difficulty of meeting the various stringent requirements, it has recently been remarked that such a goal is a formidable challenge. In an attempt to address this challenge, in this work, we have adopted a counter-intuitive approach - the deposition of the desired ferrite composition on a processed die (that contains the inductor structures along with active semiconductor circuits) by immersing it into a chemical (reactant) solution, followed by a brief irradiation of microwave frequency. However, to identify the desired ferrite composition and the appropriate recipe to deposit them, a systematic effort had to be made first, to understand the inter-relationship between synthesis process, structure of resulting material, and its physical and chemical properties. Therefore, at the beginning, a general introduction in which key concepts related to the magnetic-core inductors, the microwave-irradiation-assisted synthesis of nanostructures, the ‗state of the art‘ in the field of integration of appropriate magnetic material to the RFICs, are all outlined. As a proof of concept, microwave-irradiation-assisted solution-based deposition of zinc ferrite thin films on the technologically important Si (100) substrate is demonstrated. The highlight of the process is the use of only non-toxic metal organic precursors and aqua-alcoholic solvents for the synthesis, which is complete in 10 minutes @< 100 °C, without any poisonous by-products. Effects of various process parameters such as solute concentrations, surfactant types, and their concentrations are investigated. A wide range of deposition rates (10 - 2000 nm/min) has been achieved by tweaking the process parameters. The simultaneous formation of zinc ferrite nanocrystallites (ZFNC) along with deposition of thin film is the hallmark of this synthesis technique. Unlike its bulk counterpart, both film and powder are found upon investigation to be rich in magnetic behavior– owing to plausible cationic distribution in the crystal lattice, induced by the inherently quick and far-from-equilibrium nature of the process. The accurate estimation of magnetic characteristics in film is, however, found to be difficult due to the high substrate-to-film mass ratio. The simultaneously prepared ZFNC is examined to arrive at the optimized process recipe that imparts the desired magnetic properties to the zinc ferrite system. The crystallographic cationic distribution in zinc ferrite powder is, however, difficult to study due to the nanoscale dimension of the as prepared material. To enable crystal growth, slow and rapid annealing in air at two different temperatures are employed. The effects of these annealing schemes on various attributes (magnetic properties in particular) are studied. Rapid annealing turns out to be an interesting pathway to promote rapid grain-growth without disturbing the crystallographic site occupancies. The presence of inversion, i.e., the amount of Fe3+ in the ‗A‘-sites in the spinel structure that ideally is zero in normal spinel structure of zinc ferrite, is evident in all annealed ZFNC, as determined by Riveted analysis. Such partially inverted ZFNC exhibits soft magnetic behavior with high saturation magnetization, which can easily be ―tuned‖ by choosing appropriate annealing conditions. However, a few unique strategic modifications to the same microwave-irradiation-assisted solution-based synthesis technique are tried for the formation of nanocrystalline powder with desired sizes and properties without the necessity of anneal. The approach eventually appears to pave a way for the formation of oriented structures of zinc ferrite. The effects of anneal, nevertheless, are studied with the help of neutron powder diffractometry and magnetic measurements. The magnetic ordering at various temperatures is analyzed and connected to the magnetic measurements. The study shows that long-range magnetic ordering, present even at room temperate, originates from the distribution of cations in the partially inverted spinel structures, induced by the rapid and kinetically driven microwave synthesis. Keeping the mild nature (<200 °C) of the processing in mind, a large degree of inversion (~0.5) is a surprise and results in a very high saturation magnetization, as much as 30 emu/g at room temperature (paramagnetic in bulk), in the ZFNC system. Based on the knowledge of process-structure-property interrelationship, a recipe for the deposition of ferrite thin films by the microwave-assisted deposition technique is optimized. Successful deposition of smooth and uniform zinc ferrite thin films on various substrates is, then, demonstrated. The mystery behind the strong adherence of the film to the substrate - an unexpected outcome of a low-temperature process - is probed by XPS and the formation of silicates at the interface is identified as the probable reason. The uniformity and consistency of film composition is also examined in this chapter. Another salient feature of the process is its capability to coat any complex geometry conformally, allowing the possibility of depositing the material in a way to ―wrap around‖ the three-dimensional inductor structures of RF-CMOS. Integration of nanostructure zinc ferrite thin films onto on-chip spiral inductor structures has been demonstrated successfully. The magnetic-core inductors so obtained exhibit the highest inductance density (700 nH/mm2) and the highest Q factor (~20), reported to date, operate at 5 GHz and above, by far the highest reported to date. An increase in inductance density of as much as 20% was achieved with the use of just 1 µm thick film of zinc ferrite covering only the ―top‖ of the spiral structure, i.e., up to 20% of chip real estate can potentially be freed to provide additional functionality. The microwave-assisted solution-based deposition process described in this thesis is meant for ‗post-CMOS‘ processing, wherein the film deposited on some specific electronic components can add desired functionality to or improve the performance of a component (circuit) underneath. However, the effect of such ‗post-CMOS‘ processing on the active MOS devices, interconnects, and even inter-layer-dielectrics fabricated prior to the deposition has to be mild enough to leave the performance of delicate MOS characteristics intact. Such CMOS-compatibility of the present deposition process has been tested with a satisfactorily positive result.

No description available.

Hochfeste Leitermaterialien werden für gepulste Hochfeld-Magnetspulen benötigt, um damit die sehr hohen Magnetfelder mit einer magnetischen Flussdichte von bis zu 100 T zerstörungsfrei erzeugen zu können. Cu-Nb-Legierungen besitzen ein hohes Potential, um die widersprüchlichen Anforderungen an das Leitermaterial, wie hohe Festigkeit, hohe Leitfähigkeit und gute Verformbarkeit, zu erfüllen. Die Herstellung von Cu-Nb-Legierungen ist jedoch auf dem konventionellen Weg der Schmelzmetallurgie aufgrund der vernachlässigbar kleinen gegenseitigen Randlöslichkeit der beiden Komponenten sehr kompliziert. Die hier vorliegende Arbeit befasst sich mit Untersuchengen zur Technologie für die Herstellung von hochfesten Cu-Nb-Leitermaterialien auf der Basis der Pulvermetallurgie. Gleichermaßen ist die Entwicklung der Legierung Kerninhalt der vorliegenden Arbeit. Hierfür wurden während der einzelnen Prozessschritte sowohl die Entwicklung des Gefüges als auch die für die Anwendung relevanten Eigenschaften der Legierung untersucht und die Beziehungen zwischen Gefüge und mechanischen wie auch elektrischen Eigenschaften ermittelt.

This diploma thesis deals with measuring touches problems in industrial metrology. Thesis describes adhesive wear and tear which is caused by measuring probes when dynamical measuring is being concluded. Measuring of damaged component made of silumin and its different changes of texture by different measuring probes are evaluated. Measuring touches are made of titanium nitride, silicon nitride, zirconium, bearing chrome steel, ruby, experimental composite material and nanocrystalline diamond.

Micro- and nanostructured polymer brushes on diamond can be directly prepared by carbon templating and amplification of the latent structures by photografting of a broad variety of vinyl monomers such as styrenes, acrylates and methacrylates. Even template structures with lateral dimensions as small as 5 nm can be selectively amplified and defined polymer brush gradients of a variety of functional polymers are realizable by this technique. Furthermore, conjugation with a model protein (GFP) results in protein density gradients of high loading and improved chemical stability. The effective functionalization of chemically and biologically inert diamond surfaces with stable functional polymer brushes, the possibility of structuring by the carbon templating technique and the direct biofunctionalization are crucial steps for the development of diamond based biosensors. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.