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Suche nach „[Ruhl] [Günther]“ hat 141 Publikationen gefunden
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    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTAZ Spiegelau

    Zeitschriftenartikel

    Günther Ruhl, A. Gschwandtner, W. Lehnert

    Plasma enhanced atomic layer batch processing of aluminum doped titanium dioxide

    Journal of Vacuum Science & Technology A, vol. 30, no. 1

    2012

    DOI: 10.1116/1.3670876

    Abstract anzeigen

    Among many promising high-k dielectrics, TiO2 is an interesting candidate because of its relatively high k value of over 40 and its easy integration into existing semiconductor manufacturing schemes. The most critical issues of TiO2 are its low electrical stability and its high leakage current density. However, doping TiO2 with Al has shown to yield significant improvement of layer quality on Ru electrodes [S. K. Kim et al., Adv. Mater. 20, 1429 (2008)]. In this work we investigated if atomic layer deposition (ALD) of Al doped TiO2 is feasible in a batch system. Electrical characterizations were done using common electrode materials like TiN, TaN, or W. Additionally, the effect of plasma enhanced processing in this reactor was studied. For this investigation a production batch ALD furnace has been retrofitted with a plasma source which can be used for post deposition anneals with oxygen radicals as well as for directly plasma enhanced ALD. After evaluation of several Ti precursors a deposition process for AlTiOx with excellent film thickness and composition uniformity was developed. The effects of post deposition anneals, Al2O3 interlayers between electrode and TiO2, Al doping concentration, plasma enhanced deposition and electrode material type on leakage current density are shown. An optimized AlTiOx deposition process on TaN electrodes yields to leakage current density of 5 × 10−7 A/cm2 at 2 V and k values of about 35. Thus, it could be demonstrated that a plasma enhanced batch ALD process for Al doped TiO2 is feasible with acceptable leakage current density on a standard electrode material.

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    Zeitschriftenartikel

    A. Abrutis, T. Blomberg, Günther Ruhl, M. Lukosius, P. Baumann, C. Wenger

    ALD and AVD Grown Perovskite-type Dielectrics for Metal-Insulator-Metal Application

    (Invited)

    ECS Transactions, vol. 41, no. 2, pp. 53-61

    2011

    DOI: 10.1149/1.3633654

    Abstract anzeigen

    Atomic Vapor Deposition (AVD) and Atomic Layer Deposition (ALD) techniques were successfully applied for the depositions of perovskite type dielectrics, namely, Sr-Ta-O, Ti-Ta-O, Sr-Ti-O, Ba-Hf-O, Nb-Ta-O and Ce-Al-O. Thin films were investigated as alternative dielectrics for Metal-Insulator-Insulator (MIM) capacitors. Structural and electrical properties are investigated after depositing the metal oxides on 200 mm TiN/Si (100) substrates within the temperature range of 225-400 ºC. Electrical properties, investigated after sputtering Au top electrodes, revealed that the main characteristics are different for each dielectric. The highest dielectric constants were achieved for crystalline SrTiO3 (k=95), crystalline CeAlO3 (k = 60) and amorphous Ti-Ta-O (k = 50) films. However, Sr-Ta-O based MIM capacitors showed the lowest leakage current densities as well as the smallest capacitancevoltage linearity coefficients.

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    Zeitschriftenartikel

    T. Blomberg, Günther Ruhl, P. Baumann, C. Wenger, C. Baristiran Kaynak

    ALD grown NbTaOx based MIM capacitors

    Microelectronic Engineering, vol. 88, no. 8, pp. 2447-2451

    2011

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    Zeitschriftenartikel

    A. Abrutis, Günther Ruhl, V. Kubilius, M. Skapas, A. Zauner, M. Lukosius, C. Wenger, C. Baristiran Kaynak

    Metal-insulator-metal capacitors with MOCVD grown Ce-Al-O as dielectric

    Microelectronic Engineering, vol. 88, no. 7, pp. 1529-1532

    2011

    DOI: 10.1016/j.mee.2011.03.044

    Abstract anzeigen

    Ce–Al–O thin films were prepared on 70 nm TiN/Si(1 0 0) substrates by pulsed injection metal organic chemical vapor deposition (PI-MOCVD) for metal–insulator–metal (MIM) applications. Depositions were carried out at 400 °C using two separate Ce and Al precursors. In order to get Ce–Al–O films with different stoichiometry, Al2O3 and CeO2 were mixed with different Ce:Al precursors’ ratios. According to the XRD analysis, the as deposited films were amorphous if more aluminum was injected than cerium, and crystalline – if they are cerium rich. Electrical properties have been investigated in MIM capacitors after e-beam evaporation of Au top electrodes. Oxides possess a dielectric constant of 10–20 in combination with leakage current densities as low as 10−5 A/cm2 at −2 V. The post deposition annealing (PDA) at 600 °C and 850 °C in N2 for 5 min lead to the diffusion of Ti from TiN bottom electrode and formation of the rutile TiO2 phase. Nevertheless, CeAlO3 films were obtained if the ratio of injected Ce:Al was 1:1. The k values increased to 60 in this case, but the leakage current density worsened to 10−3 A/cm2 at −2 V.

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    Zeitschriftenartikel

    T. Blomberg, Günther Ruhl, B. Tillack, M. Lukosius, C. Wenger, C. Baristiran Kaynak

    Single SrTiO3 and Al2O3/SrTiO3/Al2O3 based MIM capacitors: Impact of the bottom electrode material

    Microelectronic Engineering, vol. 88, no. 7, pp. 1521-1524

    2011

    DOI: 10.1016/j.mee.2011.03.022

    Abstract anzeigen

    Metal–Insulator–Metal (MIM) capacitors with atomic layer deposited (ALD) single SrTiO3 dielectric and Al2O3/SrTiO3/Al2O3 multilayer dielectric have been deposited on TaN and TiN bottom electrodes. The MIM stacks have been analyzed and compared in terms of electrical and structural properties. The results indicate that MIMs with multilayer dielectrics provide better leakage current performance than the ones with single dielectrics while capacitance density is decreased. Additional Al2O3 layers prevented the crystallization of SrTiO3 in the multilayer dielectric stack. The decreased capacitance density in MIMs with multilayer dielectric is attributed to the amorphous structure of SrTiO3 and the series capacitance of top and bottom Al2O3 layers. Furthermore, MIM capacitors with single SrTiO3 dielectric layer on TiN electrodes indicated better capacitance density compared to the one with TaN electrodes. The lower capacitance density of the single SrTiO3 dielectric on TaN electrodes is correlated to the interfacial layer formation between SrTiO3 and TaN electrodes.

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    Zeitschriftenartikel

    T. Blomberg, Günther Ruhl, B. Tillack, I. Costina, M. Lukosius, C. Wenger, C. Baristiran Kaynak

    Enhanced leakage current behavior of Sr2Ta2O7-x/SrTiO3 bilayer dielectrics for metal-insulator-metal capacitors

    Thin Solid Films, vol. 519, no. 17, pp. 5734-5739

    2011

    DOI: 10.1016/j.tsf.2011.01.001

    Abstract anzeigen

    Metal–Insulator–Metal (MIM) capacitors are one of the most essential components of radio frequency devices and analog/mixed-signal integrated circuits. In order to obtain high capacitance densities in MIM devices, high-k materials have been considered to be promising candidates to replace the traditional insulators. The challenging point is that the dielectric material must demonstrate high capacitance density values with low leakage current densities. In this work, SrTiO3 based MIM capacitors have been investigated and the electrical performance of the devices have been optimized by using bilayered systems of Sr2Ta2O7−x/SrTiO3 with different thicknesses of Sr2Ta2O7−x. Sputtering X-Ray photoelectron spectroscopy (XPS) measurements have been applied to investigate the interfaces between the thin film constituents of the MIM stacks. The optimized bilayered system provides a leakage current density of 8∗10− 8 A/cm2 at 2 V (bottom electrode injection) and a high capacitance density of 13 fF/μm2.

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    Zeitschriftenartikel

    S. Rushworth, Günther Ruhl, M. Lukosius, P. Baumann, C. Wenger, C. Baristiran Kaynak

    Atomic Vapor Depositions of Ti–Ta–O thin films for Metal–Insulator–Metal applications

    Thin Solid Films, vol. 519, no. 11, pp. 3831-3834

    2011

    DOI: 10.1016/j.tsf.2011.01.239

    Abstract anzeigen

    Atomic Vapor Deposition technique was applied for the depositions of Ti–Ta–O oxide films for Metal–Insulator–Metal capacitors used in back-end of line for Radio Frequency applications. Composition, crystallinity, thermal stability and electrical properties were studied. Ti–Ta–O films, with the ratio of Ta/Ti ~ 1.5, deposited at 400 °C on TiN electrodes, were amorphous and possessed a dielectric constant of 50 with low voltage linearity coefficients and leakage currents densities as low as 10− 7 A/cm2 at 1 V. The films, deposited on Si wafers, were amorphous up to the annealing temperature of 700 °C and crystallized in orthorhombic Ta2O5 phase at higher temperatures.

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    Zeitschriftenartikel

    S. Rushworth, Günther Ruhl, M. Lukosius, C. Wenger, C. Baristiran Kaynak

    Electrical characteristics of Ti-Ta-O based MIM capacitors

    Journal of Vacuum Science & Technology B, vol. 29, no. 1

    2011

    DOI: 10.1116/1.3534020

    Abstract anzeigen

    Amorphous Ti–Ta–O thin films were deposited by the atomic-vapor deposition technique for metal-insulator-metal (MIM) applications. Depositions were carried out at 400 °C on 200-mm Si (100) wafers using TiN and TaN as bottom electrode materials. The comparison of electrical properties of MIM capacitors was done after physical-vapor deposited growth of different top electrodes, namely, Au, TiN, TaN, and Ti. Capacitance-voltage measurements revealed that the dielectric constant of 50 can be reached if Ti–Ta–O layers are deposited on TiN and if Au, TaN, or Ti is used as the top electrode. The k value is reduced to 37 if TaN is used as bottom electrode. However, if TiN is used as the top electrode, the k value of the stack is reduced by a factor of 3, from 50 to 17, independent of whether TiN or TaN are used as bottom electrodes. The lowest leakage current values (∼10−8 A/cm2) were observed when gold was used as the top electrode, whereas it increased by 3 orders of magnitude if the top electrode was changed to TiN and even more if the top electrode was changed to TaN or Ti.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTAZ Spiegelau

    Patent

    D. Groteloh, M. Melzl, M. Hammer, A. Strasser, Günther Ruhl, R. Goellner

    Method of processing a contact pad, method of manufacturing a contact pad, and integrated circuit element

    2010

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    Zeitschriftenartikel

    S. Rushworth, Günther Ruhl, B. Tillack, I. Costina, M. Lukosius, C. Wenger, C. Baristiran Kaynak

    Investigations of thermal annealing effects on electrical and structural properties of SrTaO based MIM capacitor

    Microelectronic Engineering, vol. 87, no. 12, pp. 2561-2564

    2010

    DOI: 10.1016/j.mee.2010.07.015

    Abstract anzeigen

    The annealing effects on dielectric and electrode materials in Ti/SrTaO/TaN/TiN/Ti/Si metal–insulator–metal (MIM) capacitors were studied. The electrical and structural properties were investigated after subjecting the samples to annealing temperatures of 500 °C, 700 °C and 900 °C. The electrical results revealed that the dielectric constant (k value) of Sr–Ta–O increased from 18 to 50 with increasing annealing temperature. This improvement in k value can be associated to the crystallization of dielectric layer. However, the leakage current density increased several orders of magnitudes with increase of the annealing temperatures. This observation was attributed to crystallization of dielectric, degradation of TaN electrode and out-diffusion of Si from the substrate.

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    Beitrag (Sammelband oder Tagungsband)

    J.-M. Batke, Günther Ruhl, M. Krenzer

    Development of a TiN-CVD process with very high step coverage

    Proceedings of the IEEE/SEMI Advanced Semiconductor Manufacturing Conference 2009 (ASMC '09 ; 10-12 May 2009, Berlin, Germany)

    2009

    ISBN: 978-1424436156

    DOI: 10.1109/ASMC.2009.5155948

    Abstract anzeigen

    Current high-aspect ratio devices require deposition processes for conducting barrier and electrode films in vias and trenches with increasingly high aspect ratios. In this work we studied the extension of a CVD-TiN process based on the thermal deposition from TDEAT and NH3 in combination with subsequent plasma treatment. We investigated the process parameter space (including deposition temperature, pressure, NH3/TDEAT ratio and total gas flow) applying a DoE with respect to step coverage, deposition rate and electrical resistivity. One challenge is the quantitative determination of step coverage, which we overcame by using mapping Auger Electron Spectroscopy.

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    Zeitschriftenartikel

    Günther Ruhl, S. Pasko, H.-J. Müssig, M. Lukosius, C. Wenger, C. Lohe

    Influence of the electrode material on HfO2 metal-insulator-metal capacitors

    Journal of Vacuum Science & Technology B, vol. 27, no. 1, pp. 286-289

    2009

    DOI: 10.1116/1.3071843

    Abstract anzeigen

    TaN and TiN are investigated as bottom electrode materials for metal-insulator-metal (MIM) capacitor applications. Atomic vapor deposited HfO2 films are used as high-k dielectric. The influence of the interfacial layer between HfO2 and the bottom electrode on the electrical performance of MIM capacitors is evaluated. The capacitance density as well as the capacitance voltage linearity of high-k MIM capacitors is affected by the electrode material. There is also an impact by TaN and TiN on leakage current density and breakdown strength of the devices.

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    Zeitschriftenartikel

    L. Pfitzner, S. Petersen, G. Roeder, V. Yanev, C. Manke, Günther Ruhl, M. Schellenberger, P. Baumann, A. Gschwandtner, H. Ryssel, P. Petrik

    Characterization of Ru and RuO2 thin films prepared by pulsed metal organic chemical vapor deposition

    Current Topics in Solid State Physics, vol. 5, no. 5, pp. 1231-1234

    2008

    DOI: 10.1002/pssc.200777865

    Abstract anzeigen

    Ultra‐thin ruthenium (Ru) layers were fabricated by pulsed metal organic chemical vapor deposition in an Aixtron Tricent reactor using a metal‐organic Ru precursor. Layer deposition was performed on different metal barrier combinations and on Al2O3 dielectric layers used in the fabrication of advanced Metal‐Insulator‐Metal (MIM) capacitor structures and on thermal SiO2 as reference structure. Ru layers with a thickness of 10 nm were characterized by Spectroscopic Ellipsometry (SE) and additional reference methods such as Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), and X‐Ray Reflectometry (XRR). As deposited and in situ annealed Ru layers were characterized by SE applying Drude‐Lorentz‐ and Effective Medium Approximation (EMA) models. It was shown that the deposited layers consist of a Ru‐RuO2 bilayer structure. By in situ annealing, the RuO2 layer thickness is reduced and highly pure Ru films are obtained. On the metal barriers the formation of a metal oxide interface, which is related to the deposition process, was determined.

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    Patent

    J. Mathuni, Günther Ruhl

    Process for the plasma etching of materials not containing silicon

    2006

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    Patent

    T. Lutz, Günther Ruhl, B. Schönherr, T. Franke, F. Gans, F. Erber, C. Ebi

    Verfahren zur Kompensation von Streu-/Reflexionseffekten in der Teilchenstrahllithographie

    2006

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    Patent

    T. Lutz, Günther Ruhl, B. Schönherr, T. Franke, F. Gans, F. Erber, C. Ebi

    Method for compensating for scatter/reflection effects in particle beam lithography

    2005

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    Patent

    Günther Ruhl, N. Falk

    Plasma-etching process for molybdenum silicon nitride layers on half-tone phase masks based on gas mixtures containing monofluoromethane and oxygen

    2004