Self-Consistent Subband Calculations of Al_xGa_1-xN/(AlN)/GaN-Based High Electron Mobility Transistor

Abstract:

In this paper, there is an attempt to present the two dimensional electron gas (2DEG) transport characteristics of AlxGa1-xN/(AlN)/GaN-based High Electron Mobility Transistor (HEMT) using a self-consistent numerical method for calculating the conduction-band profile and subband structure. The subband calculations take into account the piezoelectric and spontaneous polarization effects and the Hartree and exchange-correlation interaction. Here the dependency of conduction band profile, subband energies, 2DEG sheet concentration and sheet resistance on various Al mole fractions of AlxGa1-xN barrier layer are presented by incorporating simulation as well as available experimental data. Introduction of very thin binary AlN layer at the heterojunction of AlxGa1-xN/GaN resulting high mobility at high sheet charge densities by increasing the effective and decreasing alloy disorder scattering. Devices based on this structure exhibit good DC and RF performance as an increase of . Owing to high 2DEG density , the proposed device leads to operate in microwave and millimeter wave applications.

• Periodical: Advanced Materials Research (Volume 159)
• Pages: 342-347
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.159.342
• Online since: December 2010
• Authors: T.R. Lenka, A.K. Panda
• Keywords: 2DEG, Gallium Nitride (GaN), HEMT, Heterostructure, Polarisation, Subband

References

[1] M. A. Huque, S A Eliza, T Rahman, H F Huq, S K Islam: Temperature dependent analytical model for current-voltage characteristics of AlGaN/GaN power HEMT, Solid State Electronics, Vol 53 (2009), pp.341-348.

DOI: 10.1016/j.sse.2009.01.004

[2] T R Lenka and A. K. Panda: Effect of Nanoscale AlN layer for improving 2DEG Transport properties in AlGaN/AlN/GaN-based HEMT, International Journal of Pure and Applied Physics, Vol. 6 (2010), No. 4.

[3] L. Shen, S. Heikman, B. Moran, R. Coffie, N. Q. Zhang, D. Buttari, I. P. Smorchkova, S. Keller, S. P. DenBaars, and U. K. Mishra: AlGaN/AlN/GaN high-power microwave HEMT, IEEE Electron. Dev. Lett., Vol. 22 (2001), no. 10, pp.457-459.

DOI: 10.1109/55.954910

[4] T. Palacios, et. al.: High-Power AlGaN/GaN HEMTs for Ka-Band Applications, IEEE Electron Dev. Lett., Vol. 26 (2005), pp.781-783.

DOI: 10.1109/led.2005.857701

[5] Y. Zhang, I. P. Smorchkova, C. R. Elsass, S. Keller, J. P. Ibbetson, S. DenBaars, U. K. Mishra, and J. Singh: Charge control and mobility in AlGaN/GaN transistors: Experimental and theoretical studies, J. Appl. Phys. Vol. 87 (2000), pp.7981-7987.

DOI: 10.1063/1.373483

[6] O. Ambacher et al.: Two-dimensional electron gases induced by spontaneous and piezoelectric polarization in undoped and doped AlGaN/GaN heterostructures, Journal of Applied Physics, Vol. 87 (2000), no. 1, p.334–344.

DOI: 10.1063/1.371866

[7] J. C. Lin, P. Y. Yang, W. C. Tsai: Simulation and analysis of metamorphic high electron mobility transistors, Microelectronics Journal, Vol. 38 (2007), pp.251-254.

DOI: 10.1016/j.mejo.2006.11.004

[8] A Brannick, N A Zakhleniuk, B K Ridley, L F Eastman, J R Shealy, and W J Schaff: Hydrodynamic simulation of surface traps in the AlGaN/GaN HEMT, Microelectronics Journal, Vol 40 (2009), pp.410-412.

DOI: 10.1016/j.mejo.2008.06.002

[9] Kyu-Seok Lee, Doo-Hyeb Yoon, Sung-Bum Bae, Mi-Ran Park, and Gil-Ho Kim: Self-Consistent Subband Calculations of AlGaN/GaN Single Heterojunctions, ETRI Journal, Vol 24 (2002), No. 4, pp.270-278.

DOI: 10.4218/etrij.02.0102.0402

[10] G. Snider, 1D Poisson Band Diagram Calculator. South Bend, IN: Univ. of Notre Dame Press.

[11] I. P. Smorchkova, S. Keller, S. Heikman, B. Heying, P. Fini, J. S. Speck, and U. K. Mishra: Two-dimensional electron-gas AlN/GaN heterostructures with extremely thin AlN barriers, Appl. Phys. Lett., Vol. 77 (2000), No. 24, pp.3998-4000.

DOI: 10.1063/1.1332408

[12] I. P. Smorchkova, L. Chen, T. Mates, L. Shen, S. Heikman, B. Moran, S. Keller, S. P. DenBaars, J. S. Speck, and U. K. Mishra: AlN/GaN and (Al, Ga)N/AlN/GaN two-dimensional electron gas structures grown by plasma-assisted molecular-beam epitaxy, J. Appl. Phys., Vol. 90 (2001).

DOI: 10.1063/1.1412273