Advertisement

Effect of AlGaN Barrier Thickness on Trapping Characteristics in AlGaN/GaN Heterostructures

  • Apurba ChakrabortyEmail author
  • Saptarsi Ghosh
  • Subhashis Das
  • Ankush Bag
  • Dhrubes Biswas
Conference paper
Part of the Springer Proceedings in Physics book series (SPPHY, volume 215)

Abstract

Aluminum Gallium Nitride (AlGaN) barrier thickness dependent trapping characteristic of AlGaN/GaN heterostructure is investigated by frequency dependent conductance measurement. The conductance measurement in depletion region biases (−4.8 to −3.2 V) shows that the \( {\text{Al}}_{0.3} {\text{Ga}}_{0.7} {\text{N}}\left( {18\;{\text{nm}}} \right)/{\text{GaN}} \) structure suffers from both the surface (metal/AlGaN interface of gate region) and interface (AlGaN/GaN interface of channel region) trapping states, whereas the \( {\text{Al}}_{0.3} {\text{Ga}}_{0.7} {\text{N}} \left( { 25\;{\text{nm}}} \right)/{\text{GaN}} \) structure with thicker AlGaN barrier (25 nm) layer suffers from only interface trap energy states in the depletion bias region (−6.0 to −4.2 V). The calculated surface trap time constants (~2 μs) are found to be very less in \( {\text{Al}}_{0.3} {\text{Ga}}_{0.7} {\text{N}}\left( {18\;{\text{nm}}} \right)/{\text{GaN}} \) structure. This lower time constant is correlated to the electric field induced tunneling process for de-trapping of surface trap states.

Notes

Acknowledgements

Authors gratefully acknowledge project titled “ENS” sponsored by Dept. of Electronics and Information Technology (DeitY), Govt of India for providing fabrication and characterization facility.

References

  1. 1.
    A. Krost, A. Dadgar, GaN-based optoelectronics on silicon substrates. Mater. Sci. Eng. B Solid-State Mater. Adv. Technol. 93, 77–84 (2002).  https://doi.org/10.1016/S0921-5107(02)00043-0CrossRefGoogle Scholar
  2. 2.
    A. Chakraborty, D. Biswas, Comparison of trap characteristics between AlGaN/GaN and AlGaN/InGaN/GaN heterostructure by frequency dependent conductance measurement. Appl. Phys. Lett. 106, 82112 (2015).  https://doi.org/10.1063/1.4913916CrossRefGoogle Scholar
  3. 3.
    A. Chini, M. Esposto, G. Meneghesso, E. Zanoni, Evaluation of GaN HEMT degradation by means of pulsed I-V, leakage and DLTS measurements. Electron. Lett. 45, 426–427 (2009).  https://doi.org/10.1049/el.2009.0533CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Apurba Chakraborty
    • 1
    Email author
  • Saptarsi Ghosh
    • 2
  • Subhashis Das
    • 3
  • Ankush Bag
    • 3
  • Dhrubes Biswas
    • 4
  1. 1.Department of ECENIT AgartalaBarjala, JiraniaIndia
  2. 2.SSPL, DRDONew DelhiIndia
  3. 3.IIT MandiMandiIndia
  4. 4.E&ECEIIT KharagpurKharagpurIndia

Personalised recommendations