Perspective of low energy ion beam implantation for doping of graphene

• Applicants: Professor Dr. Hans Christian Hofsäss; Professor Dr. Martin Wenderoth
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2019 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 421708041

• Final Report Year: 2023

Final Report Abstract

The project "Perspective of low energy ion beam implantation for doping of graphene" was about further research into the possibility of doping graphene by means of ultra-low energy ion implantation and to change its properties in a targeted manner. The structural and electronic properties of undoped and doped graphene layers were investigated in detail at the atomic scale using scanning tunneling microscopy and -spectroscopy as well as spatially resolved electrical transport measurements. These results help to better understand and further develop the doping process. For the implantation of graphene, a new ion source was developed to extend the possibility of doping with new elemental species. This new ion source combines gas discharge sources with the principle of a sputtering source. As a result, elements with high melting temperatures and low vapor pressures are now also available for ion implantation. Another task was the lateral selective doping of a sample without using physical masks that can damage the graphene. For this purpose, an electrostatic mask was developed, which deflects the ions from an area of the sample during irradiation which thus continues undoped. By using such an electrostatic mask, the graphene remains undamaged. We were able to show that graphene can be successfully doped with different elements (boron, nitrogen) by ultralow energy ion implantation and that a gradient in the dopant concentration can be generated, an important intermediate step for the fabrication of p-n transitions in graphene.

Publications

• A comprehensive study of charge transport in Au-contacted graphene on Ge/Si(001). Applied Physics Letters, 117(2).
  Sinterhauf, Anna; Bode, Simeon; Auge, Manuel; Lukosius, Mindaugas; Lippert, Gunther; Hofsäss, Hans-Christian & Wenderoth, Martin
  
• High-Mobility Epitaxial Graphene on Ge/Si(100) Substrates. ACS Applied Materials & Interfaces, 12(38), 43065-43072.
  Aprojanz, J.; Rosenzweig, Ph.; Nguyen, T. T. Nhung; Karakachian, H.; Küster, K.; Starke, U.; Lukosius, M.; Lippert, G.; Sinterhauf, A.; Wenderoth, M.; Zakharov, A. A. & Tegenkamp, C.
  
• Substrate induced nanoscale resistance variation in epitaxial graphene. Nature Communications, 11(1).
  Sinterhauf, Anna; Traeger, Georg A.; Momeni, Pakdehi Davood; Schädlich, Philip; Willke, Philip; Speck, Florian; Seyller, Thomas; Tegenkamp, Christoph; Pierz, Klaus; Schumacher, Hans Werner & Wenderoth, Martin
  
• Breakdown of Universal Scaling for Nanometer-Sized Bubbles in Graphene. Nano Letters, 21(19), 8103-8110.
  Villarreal, Renan; Lin, Pin-Cheng; Faraji, Fahim; Hassani, Nasim; Bana, Harsh; Zarkua, Zviadi; Nair, Maya N.; Tsai, Hung-Chieh; Auge, Manuel; Junge, Felix; Hofsaess, Hans C.; De Gendt, Stefan; De Feyter, Steven; Brems, Steven; Åhlgren, E. Harriet; Neyts, Erik C.; Covaci, Lucian; Peeters, François M.; Neek-Amal, Mehdi & Pereira, Lino M. C.
  
• Unraveling the origin of local variations in the step resistance of epitaxial graphene on SiC: a quantitative scanning tunneling potentiometry study. Carbon, 184, 463-469.
  Sinterhauf, Anna; Traeger, Georg A.; Momeni, Davood; Pierz, Klaus; Schumacher, Hans Werner & Wenderoth, Martin
  
• Anomalies at the Dirac Point in Graphene and Its Hole-Doped Compositions. Physical Review Letters, 128(16).
  Pramanik, Arindam; Thakur, Sangeeta; Singh, Bahadur; Willke, Philip; Wenderoth, Martin; Hofsäss, Hans; Di Santo, Giovanni; Petaccia, Luca & Maiti, Kalobaran
  
• Laterally controlled ultra-low energy ion implantation using electrostatic masking. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 512, 96-101.
  Auge, M.; Junge, F. & Hofsäss, H.
  
• Sputter hot filament hollow cathode ion source and its application to ultra-low energy ion implantation in 2D materials. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 510, 63-68.
  Junge, Felix; Auge, Manuel & Hofsäss, Hans
  
• Lateral Controlled Doping and Defect Engineering of Graphene by Ultra-Low-Energy Ion Implantation. Nanomaterials, 13(4), 658.
  Junge, Felix; Auge, Manuel; Zarkua, Zviadi & Hofsäss, Hans