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HIGH POWER PULSED HOLLOW CATHODE PLASMA SOURCE CHARACTERIZATION V. Tiron1, A. V. Nastuta1, S. Irimiciuc1, C. Costin1, G. Popa1, C. Ionita2 and R. Schrittwieser2 1Faculty of Physics, Alexandru Ioan Cuza University of Iasi, Blvd. Carol I, no. 11, 700506, Iasi, Romania 2Institute for Ion Physics and Applied Physics, Leopold-Franzens University of Innsbruck, Technikerstr. 25, A-6020, Innsbruck, Austria Hollow cathodes (HC) discharges are rather simple plasma system used as light sources or sputtering systems. Particularly, in this type of discharge a high ion density is produced by the electron pendulum effect inside the hollow cylinder cathode. The form of hollow cathodes used as sputtering sources may vary from simple disc to cylinder [1]. Sometimes an additional cavity is used for further enhancement of the pendulum effect of the electrons inside the cathode. Thus, high-density fluxes of energetic working gas ions are produced, which intensively sputter the inner cathode walls. Usually the hollow cathode discharge operates at low pressure between 1 and 10–3 mbar, in different working gases, powered by a DC power supply. Recently, high impulse power supplies were used to ignite the HC discharge [2]. The main purpose was to optimize discharge parameters for high quality thin films deposition. One way is to increase the power density on HC in order to increase the plasma density, ionization degree, sputtering rate and therefore to improve the properties of thin films deposited. In this contribution we present experimental results concerning the electrical and optical diagnostics of a high power pulsed hollow cathode (HPP-HC) plasma source and its application for the growth of Ti thin films, nanoparticles and clusters. Plasma parameters, applied voltage and discharge current, as well as plasma potential and saturation ion current, were recorded for different pulse durations, repetition frequencies, average powers and gas pressures. These parameters were studied in order to find optimum sputtering condition for quality thin film deposition. The experimental results were obtained using a Ti hollow cathode (3 cm height and 0.5 cm inner diameter) and Ar working gas in a pressure range from 10–1 to 10–3 mbar. The high power pulse hollow cathode (up to 5 kW) was characterized by very short discharge pulses (5 µs) attaining peak cathode currents of about 6 A for a maximum applied voltage of 800 V, with a pulse repetition frequency of 10 kHz. These parameters may be suitable for cluster formation and good quality thin film growth. The titanium films obtained in these experiments were investigated by means of various material surface and bulk analysis techniques (atomic force microscopy, X-ray photoelectron spectroscopy, secondary electron microscopy, X-ray diffraction). Acknowledgments: This research has been financially supported by the CEEPUS Network No. CIII-AT0063 and bilateral project Romania-Austria No. 550/2012. References: [1] R. Schrittwieser, C. Ionita, A. Murawski, C. Maszl, M. Asandulesa, A. V. Nastuta, G. B. Rusu, C. Douat, S. B. Olenici, I. Vojvodic, M. Dobromir, D. Luca, S. Jaksch and P. Scheier, J. Plasma Phys. 76 (2010), 655. [2] I. Pilch, D. Söderström, N. Brenning and U. Helmersson, Appl. Phys. Lett. 102 (2013), 033108.