High-κ Dielectric on ReS₂: In-Situ Thermal Versus Plasma-Enhanced Atomic Layer Deposition of Al₂O₃



We report an excellent growth behavior of a high-κ dielectric on ReS₂ , a two-dimensional (2D) transition metal dichalcogenide (TMD). The atomic layer deposition (ALD) of an Al₂O₃ thin film on the UV-Ozone pretreated surface of ReS₂ yields a pinhole free and conformal growth. In-situ half-cycle X-ray photoelectron spectroscopy (XPS) was used to monitor the interfacial chemistry and ex-situ atomic force microscopy (AFM) was used to evaluate the surface morphology. A significant enhancement in the uniformity of the Al₂O₃ thin film was deposited via plasma-enhanced atomic layer deposition (PEALD), while pinhole free Al₂O₃ was achieved using a UV-Ozone pretreatment. The ReS₂ substrate stays intact during all different experiments and processes without any formation of the Re oxide. This work demonstrates that a combination of the ALD process and the formation of weak S-O bonds presents an effective route for a uniform and conformal high-κ dielectric for advanced devices based on 2D materials. © 2019 by the authors.


Includes supplementary information


Atomic layer deposition (Plasma-enhanced), Rhenium sulfide, X-ray photoelectron spectroscopy, Aluminum oxide, Atomic force microscopy, Indium compounds, Morphology, Ozone, Photoelectrons, Photons, Rhenium compounds, Sulfur compounds, Thin films, Transition metals


A Semiconductor Research Corporation (SRC) program sponsored by NIST through award number 70NANB17H041.


CC BY 4.0 (Attribution), ©2019 The Authors