Fabrication of tunnel junction-based molecular electronics and spintronics devices

  • Pawan TyagiEmail author
Research Paper


Tunnel junction-based molecular devices (TJMDs) are highly promising for realizing futuristic electronics and spintronics devices for advanced logic and memory operations. Under this approach, ~2.5 nm molecular device elements bridge across the ~2-nm thick insulator of a tunnel junction along the exposed side edge(s). This paper details the efforts and insights for producing a variety of TJMDs by resolving multiple device fabrication and characterization issues. This study specifically discusses (i) compatibility between tunnel junction test bed and molecular solutions, (ii) optimization of the exposed side edge profile and insulator thickness for enhancing the probability of molecular bridging, (iii) effect of fabrication process-induced mechanical stresses, and (iv) minimizing electrical bias-induced instability after the device fabrication. This research will benefit other researchers interested in producing TJMDs efficiently. TJMD approach offers an open platform to test virtually any combination of magnetic and nonmagnetic electrodes, and promising molecules such as single molecular magnets, porphyrin, DNA, and molecular complexes.


Molecular spintronics Molecular electronics Magnetic tunnel junctions Molecular magnets Porphyrin 



Pawan Tyagi thanks Prof. Bruce J. Hinds and the Department of Chemical and Materials Engineering, University of Kentucky for enabling his PhD research work presented in this manuscript. He also thanks D.F. Li and S.M. Holmes for providing molecules used in this paper. This paper was submitted for the refereed publication after the communication with the committee at University of Kentucky. Content of this paper were assembled to support the observation of molecule induced current suppression and changes in magnetic properties on MTJs described in PT’s PhD thesis. This paper does not necessarily reflect the views of PT’s current and past affiliating institutes.


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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  1. 1.Department of Chemical and Materials EngineeringUniversity of KentuckyLexingtonUSA
  2. 2.Department of Civil and Mechanical EngineeringUniversity of the District of ColumbiaWashingtonUSA

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