1.21. Interband tunneling current in a highly-doped nitride heterojunction

Author: Takuma Sato


We compute interband tunneling current through a highly-doped heterojunction by nextnano++ simulation and Python postprocessing. We follow the methods in the following publication, using less approximations whereever possible:

Jean-Yves Duboz and Borge Vinter. Theoretical estimation of tunnel currents in hetero-junctions: The special case of nitride tunnel junctions

This tutorial uses the Python script in the nextnanopy repository

  • nextnanopy/templates/InterbandTunneling_Duboz2019_nnp.py

to automate the simulation of the nextnano++ input file (in the sample input file folder of nextnano installation)

  • InterbandTunneling_Duboz2019_nnp.in

and post-calculation of interband tunneling current.

For the details of the formulation and the algorithm in the Python script, see

  • nextnanopy/templates/InterbandTunneling_Duboz2019_formulation.pdf


The structure is an AlGaN/GaN p-i-n junction with 2 nm GaN interlayer.

The energy overlap between the hole states and electron states increases as the bias, leading to larger tunnel current.


The Python script calculates dipole matrix elements from the simulation results:


from which we obtain the tunnel current as a function of bias:


Figure 1.21.1 Interband tunneling current in a nitride p-i-n junction. Following the paper, backward bias is taken to be positive in this plot.

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