9 research outputs found
Crystallinity, thermal diffusivity, and electrical conductivity of carbon black filled polyamide 46
Polyamide 46 (PA 46) with carbon black (CB) has been subjected to a heat treatment. Crystallinity, specific heat capacity, crystalline melting peak temperature, thermal diffusivity, and electrical conductivity were measured. The crystallinity increases with duration of thermal treatment. The maximum value is dependent on the filler fraction. A lower CB content leads to a higher crystallinity at maximum tempering time. The crystalline melting peak temperature increases with decreasing filler fraction and duration of thermal
treatment due to different crystal types and/or diverging geometric forms of the crystals. Thermal diffusivity and electrical conductivity act positively proportional to each other and increase with CB content and tempering time. The thermal diffusivity decreases with increasing temperature. The volume resistance of PA 46 is lowered by heat treatment. By CB addition in combination with a tempering process, the PA 46 can be transferred into a conductor. CB is moved by PA 46 crystals into amorphous regions forming conductive pathways
Kombination von zweiphotonenbasiertem direktem Laserschreiben mit großflächiger und hochpräziser Nanopositionierung
Die Mikro- und Nanofabrikation verspricht für die nächsten Jahre ein enormes Wachstumspotenzial, insbesondere auch im Bereich der laserbasierten Fertigung. Die hochauflösende Technik des Laserschreibens mittels Zwei-Photonen-Absorption (2PA) kann zur Herstellung von dreidimensionalen Bauteilen mit minimalen Strukturbreiten von sub-100 nm verwendet werden. Mit der optischen Präzision gehen auch Forderungen an die Präzision der Mess- und Positioniersysteme einher, um den technischen Stand von zweiphotonenbasiertem Laserschreiben weiter voranzutreiben. Die an der TU Ilmenau entwickelten Nanopositionier- und Nanomessmaschinen (NPM-Maschinen) ermöglichen eine hochgenaue und metrologisch rückführbare Positionierung mit Positionierauflösungen von 0,1 nm und einer Wiederholbarkeit von unter von 1 nm. Dabei eröffnet der Positionierbereich von 25 mm × 25 mm × 5mm bzw. von 200 mm × 200 mm × 25 mm der NPM-Maschinen ganz neue Dimensionen der skalenübergreifenden Fabrikation, sodass mikro- und sub-mikrometergenaue Artefakte bei Bauteilen mit Millimeterabmessungen erzielt werden können. In der vorliegenden Arbeit wird die Erweiterung von NPM-Maschinen zu Fabrikationsmaschinen durch die Kombination mit 2PA-Laserschreiben thematisiert. Dazu wird zunächst ein Konzept zur Integration der Zwei-Photonen-Technologie in eine NPM-Maschine entwickelt und umgesetzt. Anschließend erfolgen eine Charakterisierung des Systems sowie gezielte Untersuchungen, um den Nachweis für die Synergie der beiden Techniken zu erbringen. Es konnten diverse erfolgreiche Experimente durchgeführt werden, sodass nach Untersuchungen zur Belichtungsdosis die Herstellung von großflächigen Justiermarken gezeigt wurde. Das Potential der genauen Positionierung wird durch bahnbrechende Ergebnisse zur Abstandsreduzierung zwischen zwei geschriebenen Linien, welche die Beugungsbegrenzung unterschreiten, demonstriert. Zudem zeigten erste Versuche zur dreidimensionalen Strukturierung von Hybridpolymeren das enorme Potential für zukünftige komplexe 3D-Anwendungen in einer bisher nicht möglichen Präzision. Im Fokus stand außerdem die Entwicklung und Untersuchung eines neuen Ansatzes zur Mikro- und Nanofabrikation mit hohem Durchsatz, der auf einer Verbindung von zweiphotonenbasiertem Laserschreiben mit Feldemissionslithographie zur Herstellung von Mastern für anschließende Nanoprägelithographie basiert.Micro- and nanofabrication are promising technologies, especially in the field of laserbased manufacturing. The high-resolution technique of laser writing by means of two-photon absorption (2PA) can be used to produce three-dimensional components with minimum structure widths of sub-100 nm. The optical precision is accompanied by demands on the precision of the measuring and positioning systems in order to enhance the state of the art of two-photon based laser writing. The nanopositioning and nano-measuring machines (NPM machines) developed at the TU Ilmenau enable highly accurate and metrologically traceable positioning with positioning resolutions of 0,1 nm and a repeatability of less than 1 nm. With a positioning range of 25 mm × 25 mm × 5 mm respectively 200 mm × 200 mm × 25 mm, the NPM machines scope completely new dimensions of cross-scale fabrication, so that micro- and sub-micron precision artifacts can be achieved in components with millimeter dimensions. In this thesis, the extension from NPM machines to manufacturing machines by combining them with 2PA laser writing is discussed. Therefore, a concept for the combination of the two-photon technology with an NPM-machine is developed and successfully realized. Subsequently, the system is characterized and specific investigations are done to confirm the synergy of both technologies. An analysis of the exposure dose was done and in various experiments, the applications of the high precision and large area structuring are shown. The potential of precise positioning is demonstrated by the groundbreaking results regarding small distances between two written lines beyond the diffraction limit. In addition, first tests for three-dimensional structuring of hybrid polymers showed the enormous potential for future complex 3D applications in a precision that has not been possible so far. Additionally, a new approach for high-throughput micro- and nanofabrication based on a combination of two-photon laser writing with field emission scanning probe lithography for the production of masters for nanoimprint lithography was developed
Damping of Fe-Al Alloy Electrodeposited in an Ionic Liquid
Iron-Aluminium alloys were produced by the electro-deposition of iron-aluminium on a copper substrate. The electro-deposition process was done in the ionic liquid 1-butyl-1-methylpyrrolidinium trifluoromethylsulfonate, [Py1,4]TfO. A solution of (0.2 M FeCl2 + 2.75 M AlCl3)/ [Py1,4] TfO was used at a temperature of T=363 K because this mixture is solid at room temperature. Electrodeposited samples were studied by means of mechanical spectroscopy, differential thermal analysis and laser light microscopy. Mechanical spectroscopy studies were performed as a function of temperature, frequency and strain. The usual damping peaks for copper, low temperature grain boundary peak, recovery peak and intermediate temperature grain boundary peak were observed. In addition, a new damping peak at around 800 K which is not thermally activated was discovered. The physical mechanism controlling the appearance of this new peak is the dissolution of small precipitates or agglomerates of defects which take place at around 800 K during the warming and the subsequent re-precipitation/re-agglomeration during the cooling. This process could occur either in the copper substrate or at the Fe-Al electrodeposit.Fil: Lambri, Osvaldo Agustin F.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Exactas Ingeniería y Agrimensura. Escuela de Ingeniería Eléctrica. Laboratorio de Extensión e Investigación en Materiales; ArgentinaFil: Weidenfeller, Bernd. Technische Universitat Clausthal; AlemaniaFil: Bonifacich, Federico Guillermo. Universidad Nacional de Rosario. Facultad de Ciencias Exactas Ingeniería y Agrimensura. Escuela de Ingeniería Eléctrica. Laboratorio de Extensión e Investigación en Materiales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; ArgentinaFil: Pulletikurthi, Giridar. Technische Universitat Clausthal; AlemaniaFil: Xu, Jiayi. Technische Universitat Clausthal; AlemaniaFil: Weidenfeller, Laura. Technische Universitat Clausthal; Alemani
Two-photon direct laser writing beyond the diffraction limit using the nanopositioning and nanomeasuring machine
Since the first realization of two-photon direct laser writing (DLW) in Maruo et al. (Opt Lett 22:132-134, 1997), the manufacturing using direct laser writing techniques spread out in many laboratories all over the world. Photosensitive materials with different material properties open a new field for micro- and nanofabrication. The achievable structuring resolution using this technique is reported to be sub-100 nm (Paz et al. in J. Laser Appl. 24:042004, 2012), while a smallest linewidth of 25 nm could be shown in Tan et al. (Appl Phys Lett 90:071106, 2007). In our approach, the combination of DLW with the nanopositioning and nanomeasuring machine NMM-1 offers an improvement of the technique from the engineering side regarding the ultra-precise positioning (Weidenfeller et al. in Adv Fabr Technol Micro/Nano Opt Photon XI 10544:105440E, 2018). One big benefit besides the high positioning resolution of 0.1 nm is offered by the positioning range of 25 mm × 25 mm × 5 mm (Jäger et al. in Technisches Messen 67:319-323, 2000; Manske et al. in Meas Sci Technol 18:520-527, 2007). Thus, a trans-scale fabrication without any stitching or combination of different positioning systems is necessary. The immense synergy between the highly precise positioning and the DLW is demonstrated by the realization of resist lines and trenches whose center-to-center distance undergoes the modified diffraction limit for two-photon processes. The precise positioning accuracy enables a defined distance between illuminated lines. Hence, with a comparable huge width of the trenches of 1.655 [my]m due to a low effective numerical aperture of 0.16, a resist line of 30 nm between two written trenches could be achieved. Although the interrelationships for achieving such narrow trenches have not yet been clarified, much smaller resist lines and trench widths are possible with this approach in the near future
Thermal analysis of the ceramic material and evaluation of the bonding behavior of silicon-ceramic composite substrates
Abstract Thermal bonding of silicon and low-temperature cofired ceramics (LTCC) at sintering temperatures of 900 ° C represents currently the standard process in silicon-ceramic composite (SiCer) substrate fabrication. We analyse the thermal behavior of the LTCC using thermogravimetric analysis, differential scanning calorimetry and laser flash analysis. The thermal decomposition could be identified with a mass loss of 24% in the temperature range up to 1000 ° C what influences the thermal diffusivity with values from about 0.19 mm 2 s −1 before thermal treatment to below 0.10 mm 2 s −1 after thermal treatment. A specific heat capacity of 1 – 2 J (g · K) −1 is calculated. Further, an influence of low-temperature lamination of the LTCC seems to have an influence on the thermal behaviour. The sintering process was investigated with temperatures of 550 ° C, 730 ° C and 900 ° C, applied pressures of 12.2 kPa and 6.1 kPa and intermediate wetting layers of TiO 2 (normal deposition and oblique angle deposition). Optical observations, ultrasonic and scanning electron microscopy, and pull-tests are used to compare the properties of the sintered SiCer substrates. Whereas the sintering temperature has an obvious impact on the sintering behaviour of the LTCC, a direct conclusion of parameter variation on the bonding result was not observed
Tip- and laser-based 3D nanofabrication in extended macroscopic working areas
The field of optical lithography is subject to intense research and has gained enormous improvement. However, the effort necessary for creating structures at the size of 20 nm and below is considerable using conventional technologies. This effort and the resulting financial requirements can only be tackled by few global companies and thus a paradigm change for the semiconductor industry is conceivable: custom design and solutions for specific applications will dominate future development (Fritze in: Panning EM, Liddle JA (eds) Novel patterning technologies. International society for optics and photonics. SPIE, Bellingham, 2021. https://doi.org/10.1117/12.2593229). For this reason, new aspects arise for future lithography, which is why enormous effort has been directed to the development of alternative fabrication technologies. Yet, the technologies emerging from this process, which are promising for coping with the current resolution and accuracy challenges, are only demonstrated as a proof-of-concept on a lab scale of several square micrometers. Such scale is not adequate for the requirements of modern lithography; therefore, there is the need for new and alternative cross-scale solutions to further advance the possibilities of unconventional nanotechnologies. Similar challenges arise because of the technical progress in various other fields, realizing new and unique functionalities based on nanoscale effects, e.g., in nanophotonics, quantum computing, energy harvesting, and life sciences. Experimental platforms for basic research in the field of scale-spanning nanomeasuring and nanofabrication are necessary for these tasks, which are available at the Technische Universität Ilmenau in the form of nanopositioning and nanomeasuring (NPM) machines. With this equipment, the limits of technical structurability are explored for high-performance tip-based and laser-based processes for enabling real 3D nanofabrication with the highest precision in an adequate working range of several thousand cubic millimeters
Determination of materials and methods used in the manufacture of a Weltklang saxophone made in East Germany in 1960 by means of archaeometric techniques
El presente trabajo muestra un estudio de caracterización mediante técnicas arqueométricas, de los materiales utilizados para la fabricación de un saxofón “Weltklang” proveniente de la, por entonces, República Democrática Alemana. Para tal fin se implementaron estudios de fluorescencia de rayos X, microscopía óptica, microscopía electrónica de barrido con análisis dispersivo de energías y termogravimetría. El saxofón fue fabricado en 1960, siendo parte de la línea de saxofones Weltklang (B&S) con el número de serie 32936, y permaneció en uso hasta el año 2002. Los resultados mostraron que el material base del ejemplar era el bronce, con una composición (Cu- 28% masa Zn); la cual se ajusta a las composiciones actuales para los bronces a nivel internacional. Con respecto al plateado observable en la superficie del instrumento, los análisis realizados permitieron determinar que éste se obtuvo probablemente mediante inmersión en un baño compuesto de cianuro de plata, cianuro de potasio y carbonato de potasio; pudiéndose determinar en consecuencia no sólo el método implementado sino también la composición del compuesto utilizado para dicho tratamiento. A su vez, se encontraron diferentes tipos de imperfecciones en las muestras que corresponden principalmente al lado interior del instrumento, lo que indica la existencia de zonas falladas en el proceso de bañado, las cuales probablemente fueron reparadas por fundición local de plata sobre esas mismas áreas defectuosas. Los datos obtenidos en este estudio muestran la potencialidad del uso de técnicas arqueométricas para poder inferir los métodos utilizados para la fabricación de instrumentos musicales antiguos, y, por consiguiente, la viabilidad de la arqueometría para la reconstrucción de modos de elaboración de aquellos instrumentos musicales que puedan recuperarse en contextos arqueológicos. Al mismo tiempo, los resultados provenientes de los análisis implementados en este trabajo demuestran la aplicabilidad de la arqueometría para casos de estudios relacionados con la arqueometalurgia histórica y la arqueología industrial.The present work shows a characterization study by means of archaeometric techniques of the materials used for the manufacture of a “Weltklang” saxophone from the formerly German Democratic Republic. For fulfill this purpose, X-ray fluorescence, optical microscopy, scanning electron microscopy with dispersive energy analysis and thermogravimetry studies, were implemented. The saxophone was manufactured in 1960, being part of the Weltklang (B&S) line of saxophones with serial number 32936, and remained in use until 2002. The results showed that the base material of the sample was brass, with a composition (Cu- 28% mass Zn); which conforms to current compositions for brasses internationally. Regarding the silver layer observable on the surface of the instrument, the analyzes allowed to determine that it was probably promoted by the immersion of the instrument in a plating bath composed of silver cyanide, potassium cyanide and potassium carbonate. Therefore, the implemented method for plating the instrument and also the components of the used bath were determined. In turn, different types of imperfections were found in the samples that correspond mainly to the inner side of the instrument, which indicate the existence of faulty areas of the bathing process. These areas were probably repaired by the local deposition of melted silver above those faulty areas. The data obtained in this study show the potentiality of the use of archeometric techniques to infer the methods used in the manufacture of ancient musical instruments. Consequently, the viability of archaeometry for the reconstruction of the elaboration procedures of those musical instruments which can be recovered in archaeological contexts has been shown.Fil: Lambri, Melania Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Exactas Ingeniería y Agrimensura. Escuela de Ingeniería Eléctrica. Laboratorio de Extensión e Investigación en Materiales; Argentina. Universidad Nacional de Rosario. Facultad de Humanidades y Artes. Escuela de Antropología. Centro de Estudios de Arqueología Historica; ArgentinaFil: Weidenfeller, Laura. Ilmenau University of Technology; AlemaniaFil: Lambri, Osvaldo Agustin F.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Exactas Ingeniería y Agrimensura. Escuela de Ingeniería Eléctrica. Laboratorio de Extensión e Investigación en Materiales; Argentina. Universidad Nacional de Rosario. Facultad de Humanidades y Artes. Escuela de Antropología. Centro de Estudios de Arqueología Historica; ArgentinaFil: Weidenfeller, Bernd. Clausthal University of Technology; AlemaniaFil: Bonifacich, Federico Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Exactas Ingeniería y Agrimensura. Escuela de Ingeniería Eléctrica. Laboratorio de Extensión e Investigación en Materiales; Argentina. Universidad Nacional de Rosario. Facultad de Humanidades y Artes. Escuela de Antropología. Centro de Estudios de Arqueología Historica; ArgentinaFil: Zelada, Griselda Irene. Universidad Nacional de Rosario. Facultad de Ciencias Exactas Ingeniería y Agrimensura. Escuela de Ingeniería Eléctrica. Laboratorio de Extensión e Investigación en Materiales; Argentina. Universidad Nacional de Rosario. Facultad de Humanidades y Artes. Escuela de Antropología. Centro de Estudios de Arqueología Historica; ArgentinaFil: Rocchietti, Ana Maria. Universidad Nacional de Rosario. Facultad de Humanidades y Artes. Escuela de Antropología. Centro de Estudios de Arqueología Historica; Argentin
Metrologische Nanopositionierung kombiniert mit Zwei-Photonen-Laserdirektschreiben
The extension of nanopositioning and nanomeasuring machines (NPM-machines) to fabrication machines by using a femtosecond laser for the implementation of direct laser writing by means of two-photon absorption (2PA) is a promising approach for cross-scale metrological fabrication in the field of lithographic techniques [24]. To this end, a concept for integrating two-photon technology into an NPM machine was developed and implemented, followed by a characterization of the system and targeted investigations to provide evidence for the synergy of the two techniques. On this basis, a new approach to high-throughput micro- and nano-fabrication was developed and investigated, demonstrating new possibilities in cross-scale, high-precision manufacturing [6]. This mixand-match approach is based on a combination of 2PA laser writing with field emission lithography to fabricate masters for subsequent nanoimprint lithography. Not only the advantages of the large positioning range of the NMM-1 could be highlighted, but also the advantages resulting from the highly accurate positioning. A systematic reduction of the distance between two adjacent lines resulted in a minimum photoresist width of less than 30 nm [16], which can be classified among the smallest distances between two laser-written lines described in the literature [4, 10, 20]. The center-to-center distance of the lines of about 1.695 μm at a numerical aperture of 0.16 and a wavelength of 801 nm is only about 56 % of the Rayleigh diffraction limit extended for the two-photon process. Thus, for the first time, a resist width far below the diffraction limit could be realized with conventional two-photon laser writing in positive photoresist.507514897-
Modifications to a high-precision direct laser writing setup to improve its laser microfabrication
Two-photon-absorption (2PA) techniques enables the possibility to create extremely fine structures in photosensitive materials. For direct laser writing as micro- or nanofabrication a laser system can be combined with highly precise positioning systems. These are mostly limited by a few hundreds micrometer positioning range with applications based on piezoelectric stages or even just relatively few tens micrometer positioning range with applications based on galvanometer scanners. Although these techniques are precise, but stitching methods are required for larger fabrication areas. Therefore, a setup consisting of a femtosecond laser for 2PA and a nanopositioning and nanomeasuring machine (NMM-1) was developed for high precision laser writing on lager surfaces. Further developments of the system should enable a significant improvement in high-precision and stitching free direct laser writing. In order to combine the the femtosecond laser and the NMM-1 into a functional unit, to write complex structures with highest accuracy and homogeneity, further improvements like a beam expansion for a better use of the numerical aperture of the objective and a new femtosecond laser with a integrated power measurement are realized. This showed improvements in line width for nano strucuring. Advantages and disadvantages as well as further developments of the NMM-1 system will be discussed related to current developments in the laser beam and nanopositioning system optimization.Article 119890U1198