Now showing items 1-11 of 11

    • Al₂O₃ on WSe₂ by Ozone Based Atomic Layer Deposition: Nucleation and Interface Study 

      Azcatl, Angelica; Wang, Qingxiao; Kim, Moon J.; Wallace, Robert M.
      In this work, the atomic layer deposition process using ozone and trimethylaluminum (TMA) for the deposition of Al₂O₃ films on WSe₂ was investigated. It was found that the ozone-based atomic layer deposition enhanced the ...
    • Covalent Nitrogen Doping in Molecular Beam Epitaxy-Grown and Bulk WSe₂ 

      Khosravi, Ava; Addou, Rafik; Smyth, Christopher M.; Yue, Ruoyu; Cormier, Christopher R.; Kim, Jiyoung; Hinkle, Christopher L.; Wallace, Robert M. (American Institute of Physics Inc, 2018-10-22)
      Covalent p-type doping of WSe₂ thin films grown by molecular beam epitaxy and WSe₂ exfoliated from bulk crystals is achieved via remote nitrogen plasma exposure. X-ray photoelectron and Raman spectroscopies indicate ...
    • A Crystalline Oxide Passivation on In₀․₅₃Ga₀․₄₇As (100) 

      Qin, Xiaoye; Wang, W. -E; Droopad, R.; Rodder, M. S.; Wallace, Robert M. (American Institute of Physics Inc, 2018-09-24)
      The passivation of In₀․₅₃Ga₀․₄₇As surfaces is highly desired for transistor performance. In this study, the feasibility of a crystalline oxide passivation on In₀․₅₃Ga₀․₄₇As (100) is demonstrated experimentally. The (3 × ...
    • Dual-Gate MoS₂ Transistors with Sub-10 NM Top-Gate High-K Dielectrics 

      Bolshakov, Pavel; Khosravi, Ava; Zhao, Peng; Hurley, P. K.; Hinkle, Christopher L.; Wallace, Robert M.; Young, Chadwin D.
      High quality sub-10 nm high-k dielectrics are deposited on top of MoS₂ and evaluated using a dual-gate field effect transistor configuration. Comparison between top-gate HfO₂ and an Al₂O₃/HfO₂ bilayer shows significant ...
    • Engineering The Palladium-WSe₂ Interface Chemistry for Field Effect Transistors with High-Performance Hole Contacts 

      Smyth, Christopher M.; Walsh, Lee A.; Bolshakov, Pavel; Catalano, Massimo; Addou, Rafik; Wang, Luhua; Kim, Jiyoung; Kim, Moon J.; Young, Chadwin D.; Hinkle, Christopher L.; Wallace, Robert M. (Amer Chemical Soc, 2018-12-07)
      Palladium has been widely employed as a hole contact to WSe₂ and has enabled, at times, the highest WSe₂ transistor performance. However, there are orders of magnitude variation across the literature in Pd-WSe₂ contact ...
    • Enhancing Interconnect Reliability and Performance by Converting Tantalum to 2D Layered Tantalum Sulfide at Low Temperature 

      Lo, C. -L; Catalano, Massimo; Khosravi, Ava; Ge, W.; Ji, Y.; Zemlyanov, D. Y.; Wang, Luhua; Addou, Rafik; Liu, Y.; Wallace, Robert M.; Kim, Moon J.; Chen, Z. (Wiley-VCH Verlag, 2019-06-11)
      The interconnect half-pitch size will reach ≈20 nm in the coming sub-5 nm technology node. Meanwhile, the TaN/Ta (barrier/liner) bilayer stack has to be >4 nm to ensure acceptable liner and diffusion barrier properties. ...
    • High-κ Dielectric on ReS₂: In-Situ Thermal Versus Plasma-Enhanced Atomic Layer Deposition of Al₂O₃ 

      Khosravi, Ava; Addou, Rafik; Catalano, Massimo; Kim, Jiyoung; Wallace, Robert M. (MDPI AG, 2019-03-30)
      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 ...
    • Oxidation of GaSb(100) and its Control Studied by Scanning Tunneling Microscopy and Spectroscopy 

      Makela, J.; Tuominen, M.; Yasir, M.; Kuzmin, M.; Dahl, J.; Punkkinen, M. P. J.; Laukkanen, P.; Kokko, K.; Wallace, Robert M.
      Atomic-scale knowledge and control of oxidation of GaSb(100), which is a potential interface for energy-efficient transistors, are still incomplete, largely due to an amorphous structure of GaSb(100) oxides. We elucidate ...
    • Tuning Electronic Transport in Epitaxial Graphene-Based Van Der Waals Heterostructures 

      Lin, Yu-Chuan; Li, Jun; de la Barrera, Sergio,C.; Eichfeld, Sarah M.; Nie, Yifan; Addou, Rafik; Mende, Patrick C.; Wallace, Robert M.; Cho, Kyeongjae; Feenstra, Randall M.; Robinson, Joshua A.
      Two-dimensional tungsten diselenide (WSe₂) has been used as a component in atomically thin photovoltaic devices, field effect transistors, and tunneling diodes in tandem with graphene. In some applications it is necessary ...
    • Using Photoelectron Spectroscopy in the Integration of 2D Materials for Advanced Devices 

      Addou, Rafik; Wallace, Robert M. (Elsevier Science B.V., 2019-01-31)
      The first commercial applications of two dimensional (2D) layered materials such as graphite and MoS₂ used their lubricant properties. Following the discovery of graphene and its potential applications in various fields, ...
    • UV-Ozone Functionalization of 2D Materials 

      McDonnell, Stephen J.; Wallace, Robert M. (Springer, 2018-10-04)
      Integrating two-dimensional (2D) materials into the current nanoelectronic process requires control over the deposition of gate oxides onto these materials. Atomic layer deposition (ALD) relies on surface dangling bonds ...