TY - JOUR A1 - Lux, Helge A1 - Siemroth, Peter A1 - Sgarlata, Anna A1 - Prosposito, Paolo A1 - Schubert, Markus Andreas A1 - Casalboni, Mauro A1 - Schrader, Sigurd T1 - Synthesis of graphene-like transparent conductive films on dielectric substrates using a modified filtered vacuum arc system JF - Journal of Applied Physics N2 - Here, we present a reliable process to deposit transparent conductive films on silicon oxide, quartz, and sapphire using a solid carbon source. This layer consists of partially ordered graphene flakes with a lateral dimension of about 5 nm. The process does not require any catalytic metal and exploits a high current arc evaporation (Φ-HCA) to homogeneously deposit a layer of carbon on heated substrates. A gas atmosphere consisting of Argon or Argon/Hydrogen blend acting as a buffer influences the morphology of the growing film. scanning tunneling microscopy, transmission electron microscopy, and Raman spectra were used for a thorough characterization of the samples in order to optimize the growth parameters. The best carbon layers have a surface resistance of 5.7 × 103 Ω◻ whereas the optical transparency of the coatings is 88% with an excellent homogeneity over areas of several cm2. Such results are compatible with most semiconductor fabrication processes and make this method very promising for various industrial applications. Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-9738 SN - 1089-7550 VL - 117 IS - 19 ER - TY - GEN A1 - Beyer, Harald A1 - Hofmann, Mandy A1 - Trutz, Sebastian A1 - Lux, Helge A1 - Stissel, Sven A1 - Mehr, Wolfgang A1 - Schrader, Sigurd A1 - Siemroth, Peter T1 - Großflächige Abscheidung von Graphen - Ein wichtiger Schritt für neuartige Bauelemente T2 - Wissenschaftliche Beiträge 2013 N2 - Das wachsende Interesse an Graphen beruht auf seiner unverwechselbaren Bandstruktur und seinen damit zusammenhängenden herausragenden physikalischen Eigenschaften. Es wird daher weltweit nach einem Verfahren gesucht, Graphen großflächig und mit hoher Qualität abzuscheiden. In einer an der TH Wildau [FH] speziell für diese Aufgabe konzipierten Reaktionskammer wurde die Herstellung mittels chemischer Gasphasenabscheidung auf katalytischen Metalloberflächen für verschiedene Parameter studiert und deren Verträglichkeit mit der CMOS -Technologie untersucht. Die ersten Tests erfolgten auf Nickel, da hier eine im Volumen stattfindende katalytische Reaktion einsetzt. In weiteren Schritten fiel die Wahl auf Kupfer, da hier die Reaktion an der Oberfläche stattfindet und daher ein stabilerer Prozess realisiert werden konnte. Die Qualitätsprüfung der erzeugten Schichten erfolgte mittels Ramanspektrometrie. Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-3169 SN - 0949-8214 VL - 17 SP - 154 EP - 159 ER - TY - JOUR A1 - Fursenko, Oksana A1 - Lukosius, Mindaugas A1 - Bauer, Joachim A1 - Villringer, Claus A1 - Lux, Helge A1 - Bärwolf, Florian A1 - Lisker, Marco A1 - Mai, Andreas T1 - Diagnostic of graphene on Ge(100)/Si(100) in a 200 mm wafer Si technology environment by spectroscopic ellipsometry/reflectometry JF - Journal of Vacuum Science & Technology B N2 - Comprehensive diagnostics is a prerequisite for the application of graphene in semiconductor technologies. Here, the authors present long-term investigations of graphene on 200-mm Ge(100)/Si(100) wafers under clean room environmental conditions. Diagnostic of graphene was performed by a fast and nondestructive metrology method based on the combination of spectroscopic ellipsometry and reflectometry (SE/R), realized within a wafer optical metrology tool. A robust procedure for unambiguous thickness monitoring of a multilayer film stack, including graphene, interface layer GeOx underneath graphene, and surface roughness is developed and applied for process control. The authors found a relationship between the quality of graphene and the growth of GeOx beneath graphene. Enhanced oxidation of Ge beneath graphene was registered as a long-term process. SE/R measurements were validated and complemented using atomic force microscopy, scanning electron microscopy, Raman spectroscopy, and secondary ion mass spectrometry. This comparative study shows a high potential for optical metrology of graphene deposited on Ge/Si structures, due to its great sensitivity, repeatability, and flexibility, realized in a nondestructive way. Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-16083 VL - 37 IS - 6 PB - American Vacuum Society (AVS) ER - TY - JOUR A1 - Lux, Helge A1 - Edling, Matthias A1 - Siemroth, Peter A1 - Schrader, Sigurd T1 - Fast and Cost-Effective Synthesis of High-Quality Graphene on Copper Foils Using High-Current Arc Evaporation JF - Materials N2 - In this paper, we present an innovative and ultra-fast process for the deposition of high-quality graphene on different metal foils and thin metal films. The graphene layer can be homogeneously deposited in only 30 s process time. Due to the weak adhesion to the substrate material, the monolayer graphene is easy to transfer using the established processes. For the production, we use magnetic filtered high-current arc evaporation (Φ-HCA) with a solid, graphitic carbon source. This ultra-fast growth process can pave the way towards a cost-effective graphene synthesis for the mass production e.g., in a roll-to-roll process, avoiding time consuming established processes. KW - graphene KW - PVD KW - arc evaporation KW - copper KW - transfer KW - Φ-HCA Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-10359 SN - 1996-1944 VL - 11 IS - 5 SP - 1 EP - 10 ER - TY - THES A1 - Lux, Helge T1 - Carbon-based functional Materials for Application in Photonics, Optoelectronics and Sensorics N2 - In this work, two different processes to deposit Graphene-based transparent conductive films on arbitrary insulting substrates have been developed and examined. The first process is a PE-CVD, based on a gas mixture containing hydrocarbons (e.g. methane) inside a vacuum chamber where the insulating substrates are placed on a temperature controlled heating plate. The second process uses a pulsed filtered vacuum arc system (Phi-HCA) to homogeneously deposit a small, well defined amount of carbon on heated substrates. The substrates are tilted with respect to the particle beam and placed on a heating plate. A gas atmosphere consisting of Argon or Argon/Hydrogen decreases the particle energy and influences the morphology of the growing film. For both processes, Scanning Tunneling Microscopy (STM), Transmission Electron Microscopy (TEM) and Raman spectra have been used for a thorough characterization of the samples in order to optimize the growth parameters. Subsequently, the results (sheet resistance, Hall mobility, transmittance) have been compared with respect to the state of the art, reported in literature. The best carbon layers have a surface resistance of 5E3 Ohm_sqr while the optical transparency of the coatings is 88% with an excellent homogeneity over areas of several cm^2. Both for the PE-CVD and the Phi-HCA, the area of deposition is only limited by the respective area of the heated surface. The obtained results and the fact, that the process can be compatible with most semiconductor fabrication processes, makes them promising for various industrial applications. KW - graphene KW - carbon KW - HCA KW - PECVD KW - Raman Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-13916 ER - TY - JOUR A1 - Lux, Helge A1 - Edling, Matthias A1 - Lucci, Massimiliano A1 - Kitzmann, Julia A1 - Villringer, Claus A1 - Siemroth, Peter A1 - De Matteis, Fabio A1 - Schrader, Sigurd T1 - The Role of Substrate Temperature and Magnetic Filtering for DLC by Cathodic Arc Evaporation JF - Coatings N2 - Diamond-like carbon (DLC) films were deposited using two different types of high current arc evaporation. The first process used a magnetic particle filter to remove droplets from the plasma. For the second process, the samples were put into a metallic cage which was placed directly above the plasma source. For both processes, we varied the substrate temperature from 21 to 350 °C in order to investigate the temperature effect. The samples were characterized using SEM, AFM, XPS, Raman Spectroscopy, Ellipsometry, Photometry, and Nano Indentation in order to compare both methods of deposition and provide a careful characterization of such DLC films. We found that the sp3 content and the hardness can be precisely adjusted by changing the substrate temperature. Furthermore, in the case of unfiltered deposition, the optical constants can be shifted in the direction of higher absorbance in order to produce black and hard carbon coatings. KW - DLC KW - ta-C KW - arc evaporation KW - substrate temperature KW - hardness KW - optical constant KW - ellipsometry Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-12295 SN - 2079-6412 VL - 9 IS - 5 SP - 345 ER -