Skip to main content
SpringerLink
Log in

Impact of barrier layer thickness on DC and RF performance of AlGaN/GaN high electron mobility transistors

  • Published:
Applied Physics A Aims and scope Submit manuscript

Abstract

This work investigates the impact of barrier layer thickness on DC and RF performance of a GaN HEMT device, targeting the low noise high gain application. An optimisation workflow based on the barrier layer thickness and Al mole fraction is presented for improving the RF metrics of a GaN HEMT. AlGaN/GaN HEMTs with a gate length of 400 nm were fabricated with 22% Al content and a barrier layer thickness of 23 and 20 nm, respectively. TCAD simulation studies were carried out for different barrier thickness and Al mole fraction in accordance with the fabricated devices. Increasing the barrier thickness increases the 2-DEG density which increases the maximum drain current and results in a negative shift in the threshold voltage. With a thin barrier layer, the AlGaN/GaN HEMTs exhibit a higher transconductance due to improved gate action. The fabricated devices were investigated with the help of small-signal equivalent circuit, which demonstrate higher capacitances associated with a thin barrier layer. Apart from DC characteristics and small-signal performance, the intrinsic gain (gm/gd ratio), noise performance, and large-signal performance of the device has been investigated which provides a great contribution in creating a design subspace for a specific application (depending on the performance requirement). A thin barrier layer improves the intrinsic gain of the GaN HEMT device by 74% due to a higher transconductance and comparatively lower output conductance values. An increase in Al mole fraction increases the transconductance but is dominated by an increase in the output conductance, which in turn reduces the intrinsic gain of the device. An in-depth analysis is presented by investigating and optimising the trade-offs with barrier layer thickness and Al mole fraction towards the noise performance of the devices at microwave C- and X-band.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13

Similar content being viewed by others

Data availability

The data that support the findings of this study are available in the manuscript.

References

  1. A.S. Augustine Fletcher, D. Nirmal, A survey of Gallium Nitride HEMT for RF and high power applications. Superlattices Microstruct. 109, 519–537 (2017)

    Article  ADS  Google Scholar 

  2. S. Huang et al., Ultrathin-barrier AlGaN/GaN heterostructure: a recess-free technology for manufacturing high-performance GaN-on-Si power devices. IEEE Trans. Electron Devices 65(1), 207–214 (2018)

    Article  ADS  Google Scholar 

  3. A. Asgari et al., Electron mobility, Hall scattering factor, and sheet conductivity in AlGaN/AlN/GaN heterostructures. J. Appl. Phys. 110, 113713 (2011)

    Article  ADS  Google Scholar 

  4. G. Jiang, Y. Lv, Z. Lin, Y. Liu, M. Wang, H. Zhou, The relationship between AlGaN barrier layer thickness and polarization Coulomb field scattering in AlGaN/GaN heterostructure field-effect transistors. Superlattices Microstruct. 156, 106987 (2021)

    Article  Google Scholar 

  5. B. Mounika, J. Ajayan, B. Sandip, Investigation on impact of AlxGa1-xN and InGaN back barriers and source-drain spacing on the DC/RF performance of Fe-doped recessed T-gated AlN/GaN HEMT on SiC wafer for future RF power applications. Micro Nanostruct. 175, 207504 (2023)

    Article  Google Scholar 

  6. Z. Cong, Lu. Xiaoli, X. Tang, J. Li, Z. Shi, D. Wang, Y. He, X. Ma, Y. Hao, Ferroelectric domain induced giant enhancement of two-dimensional electron gas density in ultrathin-barrier AlGaN/GaN heterostructures. Appl. Surf. Sci. 586, 152772 (2022)

    Article  Google Scholar 

  7. W. Liu, S. Yuan, X. Fan, Suppression of hole leakage by increasing thickness of the first AlGaN barrier layer for GaN/AlGaN ultraviolet light-emitting diode. Phys. Lett. A 408, 127471 (2021)

    Article  Google Scholar 

  8. V. Tilak, B. Green, V. Kaper, H. Kim, T. Prunty, J. Smart, J. Shealy, L. Eastman, Influence of barrier thickness on the high-power performance of AlGaN/GaN HEMTs. IEEE Electron Device Lett. 22(11), 504–506 (2001)

    Article  ADS  Google Scholar 

  9. F. Medjdoub, M. Alomari, J.-F. Carlin, M. Gonschorek, E. Feltin, M.A. Py, N. Grandjean, E. Kohn, Barrier-layer scaling of InAlN/GaN HEMTs. IEEE Electron Device Lett. 29(5), 422–425 (2008)

    Article  ADS  Google Scholar 

  10. A.N. Tallaricoa, N.E. Posthumab, B. Bakerootc, S. Decoutereb, E. Sangiorgia, C. Fiegnaa, Role of the AlGaN barrier on the long-term gate reliability of power HEMTs with p-GaN gate. Microelectron. Reliability 114, 113872 (2020)

    Article  Google Scholar 

  11. J.W. Chung, W.E. Hoke, E.M. Chumbes, T. Palacios, AlGaN/GaN HEMT With 300-GHz fmax. IEEE Electron Device Lett. 31(3), 195–197 (2010)

    Article  ADS  Google Scholar 

  12. H.S. Kima, M.J. Kangb, W.H. Janga, K.S. Seob, H. Kima, H.Y. Chaa, PECVD SiNx passivation for AlGaN/GaN HFETs with ultrathin AlGaN barrier. Solid State Electron. 173, 107876 (2020)

    Article  Google Scholar 

  13. A.H. Jarndal et al., Impact of AlGaN barrier thickness and substrate material on the noise characteristics of GaN HEMT. IEEE J. Electron Devices Soc. 10, 696–705 (2022)

    Article  Google Scholar 

  14. K. Jena et al., Impact of barrier thickness on gate capacitance—modeling and comparative analysis of GaN based MOSHEMTs. J. Semicond. 36, 034003 (2015)

    Article  ADS  Google Scholar 

  15. A. Dasgupta, S. Ghosh, Y. S. Chauhan, S. Khandelwal, ASM-HEMT: compact model for GaN HEMTs. In: IEEE International Conference on Electron Devices and Solid State Circuits (EDSSC) (2015)

  16. A. Ranjan, R. Lingaparthi, N. Dharmarasu, Investigation of thin-barrier AlGaN/GaN HEMT heterostructures for enhanced gas-sensing performance. IEEE Sens. J. 22(19), 18306–18312 (2022)

    Article  ADS  Google Scholar 

  17. S. Turuvekere, A. DasGupta, N. DasGupta, Effect of barrier layer thickness on gate leakage current in AlGaN/GaN HEMTs. IEEE Trans. Electron Devices 62(10), 3449–3452 (2015)

    Article  ADS  Google Scholar 

  18. J.P. Ibbetson, P.T. Fini, K.D. Ness, S.P. DenBaars, J.S. Speck, U.K. Mishra, Polarization effects, surface states, and the source of electrons in AlGaN/GaN heterostructure field effect transistors. Appl. Phys. Lett. 77, 250 (2000)

    Article  ADS  Google Scholar 

  19. N. Goyal, B. Iniguez, T.A. Fjeldly, Analytical modeling of bare surface barrier height and charge density in AlGaN/GaN heterostructures. Appl. Phys. Lett. (2012). https://doi.org/10.1063/1.4751859

    Article  Google Scholar 

  20. I.P. Smorchkova, C.R. Elsass, J.P. Ibbetson, R. Vetury, B. Heying, P. Fini, E. Haus, S.P. DenBaars, J.S. Speck, U.K. Mishra, Polarization-induced charge and electron mobility in AlGaN/GaN heterostructures grown by plasma-assisted molecular-beam epitaxy. J. Appl. Phys. 86, 4520–4526 (1999)

    Article  ADS  Google Scholar 

  21. S. Heikman, S. Keller, Y. Wu, J.S. Speck, S.P. DenBaars, U.K. Mishra, Polarization effects in AlGaN/GaN and GaN/AlGaN/GaN heterostructures. J. Appl. Phys. 93, 10114–10118 (2003)

    Article  ADS  Google Scholar 

  22. H.W. Jang, C.M. Jeon, K.H. Kim, J.K. Kim, S.-B. Bae, J.-H. Lee, J.W. Choi, J.-L. Lee, Mechanism of two-dimensional electron gas formation in AlxGa1− xN/GaN heterostructures. Appl. Phys. Lett. 81, 1249–1251 (2002)

    Article  ADS  Google Scholar 

  23. O. Ambacher, B. Foutz, J. Smart, J.B. Shealy, N.G. Weimann, K. Chu, M. Murphy, A.J. Sierakowski, W.J. Schaff, L.F. Eastman, Two-dimensional electron gases induced by spontaneous and piezoelectric polarization in undoped and doped AlGaN/GaN heterostructures. J. Appl. Phys. 87, 334–343 (2000)

    Article  ADS  Google Scholar 

  24. R. Khan, R.K. Bag, K. Narang, Effect of fully strained AlN nucleation layer on theAlN/SiC interface and subsequent GaN growth on 4H-SiC by MOVPE. J. Mater. Sci. 30, 18910–18918 (2019)

    Google Scholar 

  25. A.K. Visvkarma, K. Sehra, C.R. Laishram, A. Malik, S. Sharma, S. Kumar, D.S. Rawal, S. Vinayak, M. Saxena, Impact of gamma radiations on static, pulsed I-V, and RF performance parameters of AlGaN/GaN HEMT. IEEE Trans. Electron Devices 69(5), 2299–2306 (2022)

    Article  ADS  Google Scholar 

  26. A.K. Visvkarma, C. Sharma, R. Laishram, S. Kapoor, D.S. Rawal, S. Vinayak, M. Saxena, Comparative study of Au and Ni/Au gated AlGaN/GaN high electron mobility transistors. AIP Adv. 9(12), 125231 (2019)

    Article  ADS  Google Scholar 

  27. Silvaco Inc., ATLAS TCAD Tool Version 5.30.R., Santa Clara, CA, USA. User Manual (2022). www.silvaco.com. Accessed 08 Oct 2022

  28. P.K. Kaushik, S.K. Singh, A. Gupta, Impact of surface states and aluminum mole fraction on surface potential and 2DEG in AlGaN/GaN HEMTs. Nanoscale Res. Lett. 16, 159 (2021)

    Article  ADS  Google Scholar 

  29. S. Sharbati, I. Gharibshahian, T. Ebel, A.A. Orouji, W.-T. Franke, Analytical model for two-dimensional electron gas charge density in recessed-gate GaN high-electron-mobility transistors. J. Electron. Mater. 50, 3923–3929 (2021)

    Article  ADS  Google Scholar 

  30. G. Dambrine, A. Cappy, F. Heliodore, E. Playez, A new method for determining the FET small-signal equivalent circuit. IEEE Trans. Microw. Theory Technol. 36(7), 1231–1236 (1988)

    Article  Google Scholar 

  31. A. Miras, E. Legros, Very high frequency small-signal equivalent circuit for short gate-length InP HEMTs. IEEE Trans. Microw. Theory Technol. 45(7), 1018–1026 (1997)

    Article  ADS  Google Scholar 

  32. A. Anand, D.S. Rawal, R. Narang, M. Mishra, M. Saxena, M. Gupta et al., A comparative study on the accuracy of small-signal equivalent circuit modelling for large gate periphery GaN HEMT with different source to drain length and gate width. Microelectron. J. 118, 105258 (2021)

    Article  Google Scholar 

  33. R.G. Brady, C.H. Oxley, T.J. Brazil, An improved small-signal parameter-extraction algorithm for GaN HEMT devices. IEEE Trans. Microw. Theory Tech. 56(7), 1535–1544 (2008)

    Article  ADS  Google Scholar 

  34. H. Fukui, Optimal noise figure of microwave GaAs MESFET’s. IEEE Trans. Electron Devices 26(7), 1032–1037 (1979)

    Article  ADS  Google Scholar 

Download references

Acknowledgements

Authors acknowledges Department of Electronic Science, University of Delhi; Solid State Physics Laboratory, Ministry of Defence, DRDO CARS project Ref. No.:1115/TS/SPL/CARS-95/2022; DBT STAR College Laboratory at Deen Dayal Upadhyaya College, University of Delhi; University of Delhi IoE Grant Ref. No.: IoE-DU/MRP/2022/056 and Department of Science and Technology project Ref. No.: SPG/2021/003067 for providing necessary tools and financial assistance for completion of this work.

Author information

Authors and Affiliations

  1. Department of Electronic Science, University of Delhi, New Delhi, 110021, India

    Anupama Anand, Khushwant Sehra,  Chanchal & Mridula Gupta

  2. Department of Electronics, Sri Venkateswara College, University of Delhi, New Delhi, 110021, India

    Rakhi Narang

  3. Solid State Physics Laboratory, Defence Research and Development Organization, New Delhi, 110054, India

    Anupama Anand,  Chanchal,  Reeta, D. S. Rawal & M. Mishra

  4. Department of Electronics, Deen Dayal Upadhyaya College, University of Delhi, New Delhi, 110078, India

    Manoj Saxena

Authors
  1. Anupama Anand
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Khushwant Sehra
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Chanchal
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Reeta
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Rakhi Narang
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. D. S. Rawal
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. M. Mishra
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Manoj Saxena
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. Mridula Gupta
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

AA: conceptualization and design, writing—original draft preparation, formal analysis, and investigation. KS: technical inputs, original draft preparation. C and R: resources/measurement data. RN: supervision, writing—reviewing and editing, technical inputs, proofreading. DSR, MM, MS and MG: supervision, proofreading, and technical inputs. Approval of the version of the manuscript: AA, KS, C, R, DSR, RN, MM, MS, MG.

Corresponding author

Correspondence to Mridula Gupta.

Ethics declarations

Conflict of interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Consent to participate

Not applicable.

Consent for publication

Not applicable.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Anand, A., Sehra, K., Chanchal et al. Impact of barrier layer thickness on DC and RF performance of AlGaN/GaN high electron mobility transistors. Appl. Phys. A 129, 563 (2023). https://doi.org/10.1007/s00339-023-06803-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s00339-023-06803-x

Keywords

Search

Navigation