Search

Your search keyword '"Lukosius, M."' showing total 149 results
Start Over Author "Lukosius, M."
149 results on '"Lukosius, M."'

1. Plasma-enhanced chemical vapor deposition of amorphous Si on graphene

Author

Lupina, G., Strobel, C., Dabrowski, J., Lippert, G., Kitzmann, J., Krause, H. M., Wenger, Ch., Lukosius, M., Wolff, A., Albert, M., and Bartha, J. W.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

Plasma-enhanced chemical vapor deposition of thin a-Si:H layers on transferred large area graphene is investigated. Radio frequency (RF, 13.56 MHz) and very high frequency (VHF, 140 MHz) plasma processes are compared. Both methods provide conformal coating of graphene with Si layers as thin as 20 nm without any additional seed layer. The RF plasma process results in amorphization of the graphene layer. In contrast, the VHF process keeps the high crystalline quality of the graphene layer almost intact. Correlation analysis of Raman 2D and G band positions indicates that Si deposition induces reduction of the initial doping in graphene and an increase of compressive strain. Upon rapid thermal annealing the amorphous Si layer undergoes dehydrogenation and transformation into a polycrystalline film whereby a high crystalline quality of graphene is preserved., Comment: 9 pages, 6 figures

Published
2016
Full Text
View/download PDF

11. Reliable metal-graphene contact formation process flows in a CMOS-compatible environment

Author

Elviretti, M., Lisker, M., Lukose, R., Lukosius, M., Akhtar, F., and Mai, A.

Subjects
Process flows, Electronics devices, Metal contacts, CMOS Compatible, Contact formation, Graphene contacts, Candidate materials, Optimisations, Formation process, Photonics devices
Abstract

The possibility of exploiting the enormous potential of graphene for microelectronics and photonics must go through the optimization of the graphene-metal contact. Achieving low contact resistance is essential for the consideration of graphene as a candidate material for electronic and photonic devices. This work has been carried out in an 8′′ wafer pilot-line for the integration of graphene into a CMOS environment. The main focus is to study the impact of the patterning of graphene and passivation on metal-graphene contact resistance. The latter is measured by means of transmission line measurement (TLM) with several contact designs. The presented approaches enable reproducible formation of contact resistivity as low as 660 Ω μm with a sheet resistance of 1.8 kΩ/□ by proper graphene patterning, passivation of the channel and a post-processing treatment such as annealing.

Published
2022
Full Text
View/download PDF

29. High-Mobility Epitaxial Graphene on Ge/Si(100) Substrates

Author

Aprojanz, J., primary, Rosenzweig, Ph., additional, Nguyen, T. T. Nhung, additional, Karakachian, H., additional, Küster, K., additional, Starke, U., additional, Lukosius, M., additional, Lippert, G., additional, Sinterhauf, A., additional, Wenderoth, M., additional, Zakharov, A. A., additional, and Tegenkamp, C., additional

Published
2020
Full Text
View/download PDF

30. Modelling of Materials for Silicon-Compatible Microelectronics

Author

Dabrowski, J., Kissinger, G., Lippert, G., Lupina, G., Lukosius, M., Sana, P., and Schroeder, T.

Abstract

Ab initio density functional theory (DFT) is an established method to model the behaviour of materials at the atomic scale. At the IHP, we use it to investigate materials systems that are of interest to the most popular and cost-efficient technology, by which electronics is made today: the silicon technology. Here we report on the results obtained for various materials: (a) for strictly 2D atomic sheets (graphene), (b) for heteroepitaxial layers (oxides and nitrides), their surfaces, and the interfaces between these films, and (c) for bulk crystals (defects in silicon). The graphene sheets are intended as components of chemical sensors, optical modulators, and high-speed and high-power transistors. The chemical reactions and diffusion processes governing the nucleation and growth of graphene on perfect (flat and stepped) and defected surfaces of germanium films were simulated, and the mechanisms responsible for the observed growth modes were elucidated. The Sc oxide and nitride films constitute the topmost part of a heterostructure on which GaN diodes, lasers, and high-power transistors can be assembled. The simulations provided insight into the intermixing of oxygen and nitrogen. The substrate on which all these films and other device structures are grown, is crystalline silicon. For numerous applications it is critical that the substrate getters (collects and binds) the impurities that are unintentionally introduced by the technological process. The formation of oxygen precipitates used as the gettering centres is associated with the presence of missing atoms (vacancies) in the Si bulk. We studied the process of vacancy clustering and oxidation, we extrapolated the clustering results to infinite separation between the defects, and we discussed the implications also for the interpretation of deep level transient spectroscopy (DLTS) or for the strategy to perform numerically expensive defect calculations (as done with hybrid potentials), among others.

Published
2018

31. Pulse-induced low-power resistive switching in HfO2 metal-insulator-metal diodes for nonvolatile memory applications.

Author

Walczyk, Ch., Wenger, Ch., Sohal, R., Lukosius, M., Fox, A., Polish_hook, J., Wolansky, D., Tillack, B., Müssig, H.-J., and Schroeder, T.

Subjects
DIODES, CONDUCTION bands, HAFNIUM oxide, COMPLEMENTARY metal oxide semiconductors, VAPOR-plating, MATHEMATICAL models, ELECTRODES, ELECTRIC fields
Abstract

The conduction process as well as the unipolar resistive switching behavior of Au/HfO2/TiN metal-insulator-metal structures were investigated for future nonvolatile memory applications. With current-voltage measurements performed at different temperatures (200–400 K), the Poole–Frenkel effect as conduction process was identified. In particular, we extracted a trap energy level at [lowercase_phi_synonym]t=0.35±0.05 eV below the HfO2 conduction band to which a microscopic origin is tentatively assigned. From current-voltage measurements of Au/HfO2/TiN structures, low-power (as low as 120 μW) resistive switching was observed. The required forming process is shown to be an energy-induced phenomenon. The characteristics include electric pulse-induced resistive switching by applying pulses up to 100 μs and a retention time upon continuous nondestructive readout of more than 104 s. [ABSTRACT FROM AUTHOR]

Published
2009
Full Text
View/download PDF

32. Microscopic model for the nonlinear behavior of high-k metal-insulator-metal capacitors.

Author

Wenger, Ch., Lupina, G., Lukosius, M., Seifarth, O., Müssig, H.-J., Pasko, S., and Lohe, Ch.

Subjects
ENERGY storage, DIELECTRIC devices, CAPACITORS, EXCITON theory, ELECTRIC resistors, PERMITTIVITY
Abstract

The achievement of sufficient capacitance-voltage linearity in metal-insulator-metal (MIM) capacitors with high permittivity (high-k) dielectrics is still a challenge, as the origin of the nonlinear behavior is still unclear. Based on fundamental physical mechanisms, such as electrostriction, Coulomb interaction between electrodes, and nonlinear optical effects, a microscopic model, which describes the nonlinearities in capacitance-voltage characteristics of high-k MIM capacitors, will be presented. The extended model, which includes stacked high-k dielectrics and interfacial layers, is able to predict the quadratic voltage capacitance coefficients as a function of the dielectric constant. The calculated coefficients are in suitable agreement with the experimental values of Al2O3-, Y2O3-, HfO2-, and Pr2Ti2O7-based MIM capacitors. [ABSTRACT FROM AUTHOR]

Published
2008
Full Text
View/download PDF

33. Pulse-induced low-power resistive switching in Hf[O.sub.2] metal-insulator-metal diodes for nonvolatile memory applications

Author

Walczyk, Ch., Wenger, Ch., Sohal, R., Lukosius, M., Fox, A., D?browski, J., Wolansky, D., Tillack, B., Mussig, H.-J., and Schroeder, T.

Subjects
Gold -- Electric properties, Hafnium -- Electric properties, Titanium -- Electric properties, Physics
Abstract

The conduction processes as well as the unipolar resistive switching behavior of Au/Hf[O.sub.2]/TiN metal-insulator-metal structures were explored to understand their use for future nonvolatile memory applications. The current-voltage measurements obtained for Au/Hf[O.sub.2]/TiN structures explain the observed low-power resistive switching process.

Published
2009

35. Graphene Synthesis and Processing on Ge Substrates

Author

Lupina, G., primary, Lukosius, M., additional, Lippert, G., additional, Dabrowski, J., additional, Kitzmann, J., additional, Lisker, M., additional, Kulse, P., additional, Krüger, A., additional, Fursenko, O., additional, Costina, I., additional, Trusch, A., additional, Yamamoto, Y., additional, Wolff, A., additional, Schroeder, T., additional, and Mai, A., additional

Published
2017
Full Text
View/download PDF

36. Metal-Free CVD Graphene Synthesis on 200 mm Ge/Si(001) Substrates

Author

Lukosius, M., primary, Dabrowski, J., additional, Kitzmann, J., additional, Fursenko, O., additional, Akhtar, F., additional, Lisker, M., additional, Lippert, G., additional, Schulze, S., additional, Yamamoto, Y., additional, Schubert, M. A., additional, Krause, H. M., additional, Wolff, A., additional, Mai, A., additional, Schroeder, T., additional, and Lupina, G., additional

Published
2016
Full Text
View/download PDF

39. Dielectric material options for integrated capacitors

Author

Ruhl, G., Lehnert, W., Lukosius, M., Wenger, C., Baristiran Kaynak, C., Blomberg, T., Haukka, S., Baumann, P.K., Besling, W.F.A., Roest, A.L., Riou, B., Lhostis, S., Halimaou, A., Roozeboom, F., Langereis, E., Kessels, W.M.M., Zauner, A., Rushworth, S.A., Ruhl, G., Lehnert, W., Lukosius, M., Wenger, C., Baristiran Kaynak, C., Blomberg, T., Haukka, S., Baumann, P.K., Besling, W.F.A., Roest, A.L., Riou, B., Lhostis, S., Halimaou, A., Roozeboom, F., Langereis, E., Kessels, W.M.M., Zauner, A., and Rushworth, S.A.

Abstract

Future MIM capacitor generations will require significantly increased specific capacitances by utilization of high-k dielectric materials. In order to achieve high capacitance per chip area, these dielectrics have to be deposited in three-dimensional capacitor structures by ALD or AVD (atomic vapor deposition) process techniques. In this study eight dielectric materials, which can be deposited by these techniques and exhibit the potential to reach k-values of over 50 were identified, prepared and characterized as single films and stacked film systems. To primarily focus on a material comparison, preliminary processes were used for film deposition on planar test devices. Measuring leakage current density versus the dielectric constant k shows that at low voltages (=1 V) dielectrics with k-values up to 100 satisfy the typical leakage current density specification of

Published
2014

42. Resistive switching behavior in TiN/HfO2/Ti/TiN devices

Author

Walczyk, D., primary, Bertaud, T., additional, Sowinska, M., additional, Lukosius, M., additional, Schubert, M. A., additional, Fox, A., additional, Wolansky, D., additional, Scheit, A., additional, Fraschke, M., additional, Schoof, G., additional, Wolf, Ch., additional, Kraemer, R., additional, Tillack, B., additional, Korolevych, R., additional, Stikanov, V., additional, Wenger, Ch., additional, Schroeder, T., additional, and Walczyk, Ch., additional

Published
2012
Full Text
View/download PDF

49. On the role of Ti adlayers for resistive switching in HfO2-based metal-insulator-metal structures: Top versus bottom electrode integration

Author

Walczyk, Ch., primary, Wenger, Ch., additional, Walczyk, D., additional, Lukosius, M., additional, Costina, I., additional, Fraschke, M., additional, Dabrowski, J., additional, Fox, A., additional, Wolansky, D., additional, Thiess, S., additional, Miranda, E., additional, Tillack, B., additional, and Schroeder, T., additional

Published
2011
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results