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An Analytical Compact Direct-Current and Capacitance Model for AlGaN/GaN High Electron Mobility Transistors

Published online by Cambridge University Press:  01 February 2011

Miao Li
Affiliation:
[email protected], Institute of Microelectronics, Institute of Microelectronics, Institute of Microelectronics, Tsinghua Univ., Beijing, 100084, China, People's Republic of, 86-10-62772373, 86-10-62771130
Xiaoxu Cheng
Affiliation:
[email protected], Institute of Microelectronics, Institute of Microelectronics, Tsinghua Univ., Beijing, 100084, China, People's Republic of
Yan Wang
Affiliation:
[email protected], Institute of Microelectronics, Institute of Microelectronics, Tsinghua Univ., Beijing, 100084, China, People's Republic of
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Abstract

We develop an analytical model for the Direct-Current (DC) and capacitance-voltage (CV) characteristics of AlGaN/GaN High Electron Mobility Transistors (HEMTs), providing accurate predictions of the transconductance and the gate capacitance in both linear and velocity saturation regions. The models provide an accurate and smooth connection in the area near the knee point for the DC characteristics, which is attributed to precise descriptions of the channel charge. An accurate model for the low-field mobility of the two dimensional electron gases (2DEG) has been developed, considering the nonmonotonic dependence of the carrier velocity on the electric field perpendicular to the channel for the first time. The calculated transconductance and output conductance are proved accurate and to have high order continuity, especially in large voltage biases, which is hard for some other analytical or numeral models. The gate capacitance has been obtained analytically and verified by experimental data. The slight decrease in the measured gate-to-source capacitance over the velocity saturation region which indicates the results of neutralization of donors and the contribution of the free electron in the AlGaN layer has been modeled accurately and smoothly for the first time. The predicted cut-off frequency is in excellent agreements with measured data over the full range of applied biases. The models are implemented into the HSPICE simulator for the DC, AC and transient simulations, with good speed and convergence characteristics.

Type
Research Article
Copyright
Copyright © Materials Research Society 2008

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References

REFERENCES

[1] Ramvall, P. Aoyagi, Y. Kuramata, A. Hacke, P. and Horino, K. Appl. Phys. Lett. 74, 3866 (1999).Google Scholar
[2] Kaper, V. Thompson, R. Prunty, T. and Shealy, J. R. IEEE Trans. MTT. 53, 55 (2005).Google Scholar
[3] Kaper, V. Thompson, R. Prunty, T. and Shealy, J. R. 11th GAAS Symposium-Munich (2003).Google Scholar
[4] Shealy, J. B. Smart, J. and Shealy, J. R. IEEE Microwave and Wireless Components Letters 11(6), 244 (2001).Google Scholar
[5] Gangwani, P. et al. , Solid-State Elec. 51, 130 (2007).Google Scholar
[6] Chattopadhyay, M. and Tokekar, S. Solid-State Elec. 50, 220 (2006).Google Scholar
[7] Li, M. and Wang, Y. IEEE TED. 55, 261 (2008).Google Scholar
[8] Li, M. and Wang, Y. Chin. Phys. Lett. 24, 2998 (2007).Google Scholar
[9] George, G. and Hauser, J. IEEE TED. 37, 1193 (1990).Google Scholar
[10] Wu, Y. et al. , IEEE Elec. Dev. Lett. 18, 290 (1997).Google Scholar
[11] Haldar, Rashmi S. and Gupta, R. S. Microwave and Optical Tech. Lett. 29, 117 (2001).Google Scholar
[12] Asgaria, A. Kalafia, M. and Faraone, L. Physica E 28, 491 (2005).Google Scholar
[13] Aktas, O. Fan, Z. Mohammad, S. Botchkarev, A. and Morkoc, H. Appl. Phys. Lett. 69, 3872 (1996).Google Scholar
[14] Lee, J. W. and Webb, K. J. IEEE Trans. MTT. 52, 2 (2004).Google Scholar
[15] Moon, J. S. et al. , IEEE Elec. Dev. Lett. 23, 637 (2002).Google Scholar