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Title: Lateral Graphene p–n Junctions Realized by Nanoscale Bipolar Doping Using Surface Electric Dipoles and Self‐Organized Molecular Anions

Lateral p–n junctions take the unique advantages of 2D materials, such as graphene, to enable single‐atomic layer microelectronics. A major challenge in fabrication of the lateral p–n junctions is in the control of electronic properties on a 2D atomic sheet with nanometer precision. Herein, a facile approach that employs decoration of molecular anions of bis‐(trifluoromethylsulfonyl)‐imide (TFSI) to generate p‐doping on the otherwise n‐doped graphene by positively polarized surface electric dipoles (pointing toward the surface) formed on the surface oxygen‐deficient layer “intrinsic” to an oxide ferroelectric back gate is reported. The characteristic double conductance minimaVDirac−andVDirac+illustrated in the obtained lateral graphene p–n junctions can be tuned in the range of −1 to 0 V and 0 to +1 V, respectively, by controlling the TFSI anions and surface dipoles quantitatively. The unique advantage of this approach is in adoption of polarity‐controlled molecular ion attachment on graphene, which could be further developed for various lateral electronics on 2D materials.

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Award ID(s):
1508494 1809293 1909292
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials Interfaces
Medium: X
Sponsoring Org:
National Science Foundation
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