Skip to main content
SpringerLink
Log in

The ALD Films of Al2O3, SiNx, and SiON as Passivation Coatings in AlGaN/GaN HEMT

  • Published:
Russian Microelectronics Aims and scope Submit manuscript

Abstract

In the field-effect transistors based on the wide-band-gap nitride heterostructures, the dielectric layers are in widespread use as one of the main elements in the active regions of the devices and the passivation layers. Stringent requirements are imposed on the dielectrics in terms of the high dielectric capacitance, large band-gap energy, and the coating integrity. Furthermore, the films must withstand high electric fields and have a low surface state density in the dielectric/semiconductor interface. For these purposes, the low temperature films grown by plasma-enhanced chemical vapor deposition, atomic layer deposition (ALD), and plasma-enhanced deposition are usually used as effective coatings. The ALD films of Al2О3, SiNх (Si3N4), SiON, and ALD AlN are used most often, and offer the greatest promise for the AlGaN/GaN heterostructures. The influence of the passivation of the ALD Al2O3, SiNx, and SiON coatings of various thicknesses on the change of the charge and the density of the states of the AlGaN/GaN heterostructures is investigated. The physical parameters of the structures are estimated by the C–V characteristics measured on various frequencies and the I–V characteristics. It is demonstrated, according to the examined energy band diagrams of the structures at various control voltages, and estimation of the elemental composition of the films by the method of Auger electron spectroscopy, that the reason for the generation of a high positive charge at the deposition of the ALD Al2O3 and SiNx films is the occurrence of an additional piezoelectric charge in the buffer layer of AlGaN. It is demonstrated that use of the SiON films with the oxygen concentration in them higher than 3% does not result in the generation of an additional positive charge but can initiate current fluctuations during the measurement of the I–V characteristics. A possible mechanism of carrier transport in the space charge region resulting in such fluctuations is discussed.

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.

Similar content being viewed by others

REFERENCES

  1. Chevtchenko, S.A., Reshchikov, M.A., Fan, Q., Ni, X., Moon, Y.T., Baski, A.A., and Morkoç, H., Study of SiNx and SiO2 passivation of GaN surfaces, J. Appl. Phys., 2007, vol. 101, no. 11, p. 2740324.https://doi.org/10.1063/1.2740324

    Article  Google Scholar 

  2. Mizue, C., Hori, Y., Miczek, M., and Hashizume, T., Capacitance-voltage characteristics of Al2O3/AlGaN/ GaN structures and state density distribution at Al2O3/AlGaN Interface, Jpn. J. Appl. Phys., 2011, vol. 50, N 2R, p. 021001. https://doi.org/10.1143/JJAP.50.021001

    Article  Google Scholar 

  3. Matys, M., Stoklas, R., Blaho, M., and Adamowicz, B., Origin of positive fixed charge at insulator/AlGaN interfaces and its control by AlGaN composition, J. Appl. Phys., 2017, vol. 110, no. 24, p. 243505. https://doi.org/10.1063/1.4986482

    Article  Google Scholar 

  4. Geng, K., Chen, D., Zhou, Q., and Wang, H., AlGaN/ GaN MIS-HEMT with PECVD SiNx, SiON, SiO2 as gate dielectric and passivation layer, Electronics, 2018, vol. 7, no. 12, p. 416. https://doi.org/10.3390/electronics7120416

    Article  Google Scholar 

  5. Matys, M., Adamowicz, B., Domanowska, A., Michalewicz, A., Stoklas, R., Akazawa, M., Yatabe, Z., and Hashizume, T., On the origin of interface states at oxide/III-nitride heterojunction interfaces, J. Appl. Phys., 2016, vol. 120, no. 22, p. 225305. https://doi.org/10.1063/1.4971409

    Article  Google Scholar 

  6. Shengyin Xie, Jiayun Yin, Sen Zhang, Bo Liu, Wei Zhou, and Zhihong Feng, Trap behaviors in AlGaN–GaN heterostructures by C–V characterization, Solid-State Electron., 2009, vol. 53, no. 11, pp. 1183–1185. https://doi.org/10.1016/j.sse.2009.08.006

    Article  Google Scholar 

  7. Zubkov, V.I., Characterization of InxGa1–xAs/GaAs quantum-well heterostructures by C–V measurements: band offsets, quantum-confinement levels, and wave functions, Semiconductors, 2007, vol. 41, no. 3, pp. 320—326. https://doi.org/10.1134/S1063782607030153

    Article  Google Scholar 

  8. Miczek, M., Mizue, C., Hashizume, T., and Adamowicz, B., Effects of interface states and temperature on the C–V behavior of metal/insulator/AlGaN/GaN heterostructure capacitors, J. Appl. Phys., 2008, vol. 103, no. 10, p. 104510. https://doi.org/10.1063/1.2924334

    Article  Google Scholar 

  9. Arulkumaran S., Egawa T., Ishikawa H., and Jimbo, T., Characterization of different –Al-content AlxGa1–xN/GaN heterostructures and high-electron-mobility transistors on sapphire, J. Vacuum Sci. Technol. B, 2003, vol. 21, no. 2, pp. 888–894. https://doi.org/10.1116/1.1556398

    Article  Google Scholar 

  10. Hashizume, T. and Hasegawa, H., Effects of nitrogen deficiency on electronic properties of AlGaN surfaces subjected to thermal and plasma processes, Appl. Surf. Sci., 2004, vol. 234, nos. 1–4, pp. 387—394. https://doi.org/10.1016/j.apsusc.2004.05.091

    Article  Google Scholar 

  11. Dinara, S.M., Jana, S.Kr., Ghosh, S., Mukhopadhyay, P., Kumar, R., Chakraborty, A., Bhattacharya, S., and Biswas, D., Enhancement of two dimensional electron gas concentrations due to Si3N4 passivation on Al0.3Ga0.7N/GaN heterostructure: Strain and interface capacitance analysis, AIP Adv., 2015, vol. 5, no. 4, p. 047136. https://doi.org/10.1063/1.4919098

    Article  Google Scholar 

  12. Sameer, J.J., Surface and mechanical stress effects in AlGaN/GaN high electron mobility transistors, Ph. D. Thesis, Massachusetts Inst. Technol., 2017. https:// dspace.mit.edu/handle/1721.1/111325.

  13. Mosca, R., Gombia, E., Passaseo, A., Tasco, V., Peroni, M., and Romanini, P., DLTS characterization of silicon nitride passivated AlGaN/GaN heterostructures, Superlatt. Microstruct., 2004, vol. 36, nos. 4–6, pp. 425–433. https://doi.org/10.1016/j.spmi.2004.09.006

    Article  Google Scholar 

  14. Hori, Y., Mizue, C., and Hashizume, T., Process conditions for improvement of electrical properties of Al2O3/n-GaN structures prepared by atomic layer deposition, Jpn. J. Appl. Phys., 2010, vol. 49, no. 8R, p. 080201. https://doi.org/10.1143/JJAP.49.080201

    Article  Google Scholar 

  15. Hashizume, T., Alekseev, E., Pavlidis, D., Boutros, K.S., and Redwing, J., Capacitance-voltage characterization of AlN/GaN metal-insulator-semiconductor structures grown on sapphire substrate by metalorganic chemical vapor deposition, J. Appl. Phys., 2000, vol. 88, no. 4, p. 1983–1986. https://doi.org/10.1063/1.1303722

    Article  Google Scholar 

  16. Eller, B.S., Yang, J., and Nemanich, R.J., Electronic surface and dielectric interface states on GaN and AlGaN, J. Vacuum Sci. Technol. A, 2013, vol. 31, no. 5, p. 050807. https://doi.org/10.1116/1.4807904

    Article  Google Scholar 

  17. Dusza, J. and Steen, M., Microhardness load/size effect in individual grains of a gas pressure sintered silicon nitride, J. Am. Ceram. Soc., 1998, vol. 81, no. 11, pp. 3022–3024.

    Article  Google Scholar 

  18. Yakovleva, N.I., Nikonov, A.V., Boltar, K.O., and Sednev, M.V., Analysis of current-voltage characteristics in UV AlGaN heterostructure FPAS, Usp. Prikl. Fiz., 2018, vol. 6, no. 1, pp. 44–55.

    Google Scholar 

  19. Monroe, D., Hopping exponential band tails, Phys. Rev. Lett., 1985, vol. 54, no. 2, pp. 146–149. https://doi.org/10.1103/PhysRevLett.54.146

    Article  Google Scholar 

  20. Bochkareva, N.I., Voronenkov, V.V., Gorbunov, R.I., Shreter, Y.G., Virko, M.V., Kogotkov, V.S., Leonidov, A.A., Vorontsov-Velyaminov, P.N., and Sheremet, I.A., Hopping conductivity and dielectric relaxation in Schottky barriers on GaN, Semiconductors, 2017, vol. 51, no. 9, pp. 1186–1193. https://doi.org/10.1134/S1063782617090068

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. AO NPP Pulsar, 105187, Moscow, Russia

    K. L. Enisherlova, E. M. Temper, Yu. V. Kolkovsky, B. K. Medvedev & S. A. Kapilin

Authors
  1. K. L. Enisherlova
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. E. M. Temper
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Yu. V. Kolkovsky
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. B. K. Medvedev
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. S. A. Kapilin
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to K. L. Enisherlova.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Enisherlova, K.L., Temper, E.M., Kolkovsky, Y.V. et al. The ALD Films of Al2O3, SiNx, and SiON as Passivation Coatings in AlGaN/GaN HEMT. Russ Microelectron 49, 603–611 (2020). https://doi.org/10.1134/S106373972008003X

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1134/S106373972008003X

Keywords:

Search

Navigation