Journal of Materials Science: Materials in Electronics

, Volume 29, Issue 22, pp 19353–19358 | Cite as

Reduction of leakage current at the SiNx/GaN interface in GaN Schottky diodes

  • Sowmya KolliEmail author
  • Mahendra Sunkara
  • Bruce Alphenaar


The breakdown characteristics for a GaN wrapround field plate diode are compared to those of a planar diode and a mesa diode to determine the improvement due to the field plate geometry. Mesa diodes exhibit a higher breakdown voltage compared to planar diodes, in agreement with simulation models. Wraparound field plate diodes, however, show high leakage current resulting in lower breakdown values than predicted. It is found that the extra leakage is caused by damage from the plasma enhanced chemical vapor deposition of the SiNx used to form the field plate. To mitigate the leakage current, atomic layer deposition was used to put down a protective Al2O3 prior to SiNx deposition. This significantly reduced the leakage current and raised the breakdown voltage of the wraparound Schottky diodes.



Authors acknowledge the support from endowment for Renewable and Sustainable Energy Research at Conn Center for Renewable Energy Research, University of Louisville.

Supplementary material

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Supplementary material 1 (PNG 186 KB)
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Supplementary material 2 (PNG 75 KB)


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Sowmya Kolli
    • 1
    Email author
  • Mahendra Sunkara
    • 2
  • Bruce Alphenaar
    • 1
  1. 1.Department of Electrical and Computer EngineeringUniversity of LouisvilleLouisvilleUSA
  2. 2.Department of Chemical EngineeringUniversity of LouisvilleLouisvilleUSA

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