| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2016) | |
| Thin Films | Tuesday Sessions |
| Session TF-TuE |
| Session: | Growth & Characterization of 2D Materials |
| Presenter: | Sebastian Funke, Accurion GmbH, Germany |
| Authors: | S. Funke, Accurion GmbH, Germany U. Wurstbauer, Walter Schottky Institute and Physics Department, TU München E. Parzinger, Walter Schottky Institute and Physics Department, TU München B. Miller, Walter Schottky Institute and Physics Department, TU München P. Thiesen, Accurion GmbH, Germany |
| Correspondent: | Click to Email |
Characterizing 2D-materials and Hetero-structure of MoS2 and WSe2 by Spectroscopic Imaging Ellipsometry
Sebastian Funke1, Ursula Wurstbauer2,3, Eric Parzinger 2,3, Bastian Miller2,3 , Peter H. Thiesen1
1. Accurion GmbH, Stresemanstraße 30, 37079 Göttingen, Germany
2. Walter Schottky Institute and Physics-Department, TU München, Garching 85748, Germany
3. Nanosystems Initiative Munic 80799, Germany
By stacking different 2D-materials into hetero-structures new optoelectronic devices are formed[1,2]. The advantage of these new hetero-structures compared to conventional devices may be superior material properties and its significant lower height. For the design of efficient hetero-structures the knowledge of the materials properties is essential. We show that spectroscopic imaging ellipsometry (SIE) is capable of measuring the optical properties of different types of 2D-materials. With the lateral resolution down to 1 µm SIE is able to localize and characterize small flakes of e.g. 2D-materials. It also enables the characterization of stacked materials.
In the talk we present spectral investigations on Molybdenum-disulphide from the UV- to NIR. To describe the dispersion for MoS2 an anisotropic approach is shown[3]. It reveals an anisotropic behaviour in the out-of-plane direction. Further, investigations on a hetero-structure of MoS2 and WSe2 are done as seen in Figure 1. All regions can be measured simultaneously, so a comparison of the spectral response of the single 2D-materials can be compared to the stacked response. Spectral investigations around the bandgap of MoS2 at around 650 nm will be shown and discussed for the overlapping and non-overlapping regions.
Figure 1: Heterostructure of MoS2 and WSe2. Green area denotes the overlapping hetero-structure.
References
[1] L. Britnell, R. M. Ribeiro, A. Eckmann, R. Jalil, B. D. Belle, A. Mishchenko, Y.-J. Kim, R. V. Gorbachev, T. Georgiou, S. V. Morozov,
and others, Strong light-matter interactions in heterostructures of atomically thin films, Science, 340, 1311–1314, (2013).
[2] G.-H. Lee, Y.-J. Yu, X. Cui, N. Petrone, C.-H. Lee, M. S. Choi, D.-Y. Lee, C. Lee, W. J. Yoo, K. Watanabe, T. Taniguchi, C. Nuckolls, P. Kim, and J. Hone, Flexible and Transparent MoS 2 Field-Effect Transistors on Hexagonal Boron Nitride-Graphene Heterostructures, ACS Nano, 7, 7931–7936, (2013).
[3] S. Funke, B. Miller, E. Parzinger, A. Holleitner, P. H. Thiesen, U. Wurstbauer, Spectroscopic Imaging Ellipsometry of MoS2, Journal Of Physics: Condensed Matter, accepted July 2016