TY - JOUR A1 - Nick, Christoph A1 - Joshi, Ravi A1 - Schneider, Jörg A1 - Thielemann, Christiane T1 - Three-Dimensional Carbon Nanotube Electrodes for Extracellular Recording of Cardiac Myocytes JF - Biointerphases, 2012 N2 - Three-Dimensional Carbon Nanotube Electrodes for Extracellular Recording of Cardiac Myocytes KW - nanotube electrodes KW - Kohlenstoff-Nanoröhre Y1 - 2012 U6 - https://doi.org/10.1007/s13758-012-0058-2 VL - 7 SP - 58 PB - Springer-Verl. ER - TY - JOUR A1 - Nick, Christoph A1 - Yadav, Sandeep A1 - Joshi, Ravi A1 - Schneider, Jörg A1 - Thielemann, Christiane T1 - A three-dimensional microelectrode array composed of vertically aligned ultra-dense carbon nanotube networks JF - Applied Physics Letters N2 - Electrodes based on carbon nanotubes are a promising approach to manufacture highly sensitive sensors with a low limit of signal detection and a high signal-to-noise ratio. This is achieved by dramatically increasing the electrochemical active surface area without increasing the overall geometrical dimensions. Typically, carbon nanotube electrodes are nearly planar and composed of randomly distributed carbon nanotube networks having a limited surface gain for a specific geometrical surface area. To overcome this limitation, we have introduced vertically aligned carbon nanotube (VACNT) networks as electrodes, which are arranged in a microelectrode pattern of 60 single electrodes. Each microelectrode features a very high aspect ratio of more than 300 and thus a dramatically increased surface area. These microelectrodes composed of VACNT networks display dramatically decreased impedance over the entire frequency range compared to planar microelectrodes caused by the enormous capacity increase. This is experimentally verified by electrochemical impedance spectroscopy and cyclic voltammetry. KW - Microelectrode arrays KW - Electrochemical impedance spectroscopy KW - Chemical compounds and components KW - Electrolytes KW - Signal processing KW - Mikroelektrode KW - Array KW - Kohlenstoff-Nanoröhre Y1 - 2015 U6 - https://doi.org/10.1063/1.4926330 VL - 2015 IS - 107 SP - 1 EP - 1 ER - TY - CHAP A1 - Nick, Christoph A1 - Thielemann, Christiane A1 - Joshi, Ravi A1 - Schneider, Jörg T1 - Niedrigtemperatur-Transfer von vertikal ausgerichteten Kohlenstoff Nanoröhren auf Mikrostrukturen T2 - Mikro-Nano-Integration - 3. GMM-Workshop, Stuttgart, Deutschland, 2011 N2 - Vertikal angeordnete Kohlenstoff Nanoröhren (engl. vertically aligned carbon nanotubes; VA-CNT) können seit einigen Jahren mit hoher Reproduzierbarkeit durch CVD-Verfahren bei 600 °C - 800 °C auf Katalysatorschichten aus Aluminium und Eisen hergestellt werden. Sie zeigen sehr gute Eigenschaften im Bereich der Feldemission, aber auch in sub-µm Vias. Allerdings sind die relativ hohen Temperaturen oft nicht prozesskompatibel und müssen vermieden werden um keine Degradation darunterliegender Strukturen in Kauf zu nehmen. Da die Reduzierung der CVD-Temperaturen beim Wachstum der VA-CNTs unter 600 °C zu hohen Defektraten führt, schlagen wir ein neues Verfahren zum Transfer der VA-CNTs bei niedrigen Temperaturen vor. In einer Kombination aus Flip-Chip- und Stempel-Technik werden hoch geordnete, mikrostrukturierte VA-CNTs auf temperaturempfindliche Substrate aus Kalk-Natron-Glas, Gold oder Kupfer bei Temperaturen von 100 °C transferiert. Die vertikale Struktur der Nanoröhren bleibt dabei erhalten. Eine leitende Verbindung kann durch ein leitfähiges, bio-kompatibles Polymer gewährleistet werden, was eine Erweiterung des Einsatzbereichs auf Life-Science Applikationen erlauben würde. KW - Kohlenstoff-Nanoröhre Y1 - 2011 ER - TY - CHAP A1 - Yilmazoglu, Oktay A1 - Al-Daffaie, Shihab A1 - Hartnagel, Hans A1 - Joshi, Ravi A1 - Yadav, Sandeep A1 - Schneider, Jörg A1 - Nick, Christoph A1 - Thielemann, Christiane T1 - CNT photocathodes based on GaAs high-frequency photoswitches T2 - 25th International Vacuum Nanoelectronics Conference, 9 - 13 July 2012, Jeju, South Korea N2 - A high-frequency photocathode based on carbon nanotube (CNT) blocks on semiisolating GaAs or low-temperature grown GaAs was fabricated and used for electron emission in a diode configuration. The CNT blocks can achieve high currents and current densities of I=0.5 mA and J=28 mA/cm 2 at E=2.1 V/μm, respectively. The photomodulation was achieved with a GaAs photoswitch electrically connected to the bottom of the CNT block emitter. This photocathode can find applications in high frequency tubes and optically driven X-ray sources. KW - Kohlenstoff-Nanoröhre Y1 - 2012 U6 - https://doi.org/10.1109/IVNC.2012.6316840 ER - TY - JOUR A1 - Nick, Christoph A1 - Joshi, Ravi A1 - Schneider, Jörg A1 - Thielemann, Christiane T1 - Low Temperature Substrate Transfer Technique for 3D Vertically Aligned Carbon Nanotube Architectures JF - International Journal of Surface Science and Engineering KW - nanotube architectures KW - Kohlenstoff-Nanoröhre Y1 - 2012 U6 - https://doi.org/10.1504/IJSURFSE.2012.049057 VL - 6 IS - 3 SP - 246 EP - 246 ER - TY - CHAP A1 - Nick, Christoph A1 - Joshi, Ravi A1 - Schlaak, Helmut A1 - Schneider, Jörg A1 - Thielemann, Christiane T1 - Multi electrode array with carbon nanotube electrodes for the extra-cellular detection of action potentials T2 - MikroSystemTechnik Kongress 2011, Darmstadt KW - Mehrfachelektrode KW - Elektrodenarray Y1 - 2014 ER - TY - JOUR A1 - Nick, Christoph A1 - Yadav, Sandeep A1 - Joshi, Ravi A1 - Schneider, Jörg A1 - Thielemann, Christiane T1 - Growth of Cortical Neurons Grown on Randomly Oriented and Vertically Aligned Dense Carbon Nanotube Networks JF - Beilstein Journal of Nanotechnology KW - Nervenzelle KW - Zellwachstum Y1 - 2014 VL - 5 SP - 1575 EP - 1579 ER -