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arXiv · 2001.07860

Investigation of laser-induced-metal phase of $\mathrm{MoTe}_{2}$ and its contact property via scanning gate microscopy

Kohei Sakanashi·Hidemitsu Ouchi·Kota Kamiya·Peter Krüger·Katsuhiko Miyamoto·Takashige Omatsu·Keiji Ueno·Kenji Watanabe·Takashi Taniguchi·Jonathan P. Bird·Nobuyuki Aoki
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Abstract

Although semiconductor to metal phase transformation of MoTe$_{2}$ by high-density laser irradiation of more than 0.3 MW/cm$^{2}$ has been reported, we reveal that the laser-induced-metal (LIM) phase is not the 1T' structure derived by a polymorphic-structural phase transition but consists instead of semi-metallic Te induced by photo-thermal decomposition of MoTe$_{2}$. The technique is used to fabricate a field effect transistor with a Pd/2H-MoTe$_{2}$/LIM structure having an asymmetric metallic contact, and its contact properties are studied via scanning gate microscopy. We confirm that a Schottky barrier (a diffusion potential) is always formed at the Pd/2H-MoTe$_{2}$ boundary and obstacles a carrier transport while an Ohmic contact is realized at the 2H-MoTe$_{2}$/LIM phase junction for both n- and p-type carriers.

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Kohei Sakanashi, Hidemitsu Ouchi, Kota Kamiya, Peter Krüger, Katsuhiko Miyamoto, Takashige Omatsu, Keiji Ueno, Kenji Watanabe, Takashi Taniguchi, Jonathan P. Bird, Nobuyuki Aoki. 2020-01-22. Investigation of laser-induced-metal phase of $\mathrm{MoTe}_{2}$ and its contact property via scanning gate microscopy. https://doi.org/10.1088/1361-6528/ab71b8

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