Chapter 39
An Analytical Model for AlGaN/GaN
MOS-HEMT for High Power
Applications
Nguyen-Trung Do, Nguyen-Hoang Thoan, Tran Minh Quang,
Dao Anh Tuan, and Nguyen-Ngoc Trung
Abstract We develop a physics based analytical model for AlGaN/GaN high elec-
tron mobility transistors (HEMT and MOS-HEMT) to study the I-V characteristics,
current transfer characteristics, transconductance and drain-conductance. The model
is modified from a model first presented by Chang and Fetterman for AlGaAs/GaAs
HEMT (Chang and Fetterman in Solid-State Electron 30(5), 1987 [1], IEEE Trans
Electron Dev Ed-34(I), 1987 [2]) The linear and non-linear drain currents have been
separately calculated and merged them in order to evaluate the I-V characteristics.
The threshold voltage has been evaluated from current transfer characteristics plot
and verified from the transconductance parameter. We also consider the effect of
polarization on threshold voltage of the devices. Moreover, to prove the exactness
of our model, we compare our data with our experiment data for common HEMT,
Hasan’s MOS-HEMT and Yoon’s HEMT with short channel.
39.1 Introduction
Nowadays, the development of power devices and modern applications such as smart
phone, electric converter is helping our life became more convenience. The classic
Si-based devices has reached limitation so it’s difficult to create new one with better
performances. GaN-based high electron mobility Transistors (HEMTs) are emerging
as great candidates for high-temperature, high-power and radio-frequency (RF) elec-
tronics due to their unique capabilities of achieving higher current density, higher
breakdown voltage, higher operating temperatures and higher cut-off frequencies
compared to silicon (Si) [3]. Due to higher breakdown voltage, up to 2 × 10
6
V/cm,
GaN MOSFET and GaN/AlGaN HEMT can operate at higher temperature and power
than that of Si MOSFET and GaAs HEMT [3, 4]. Moreover, GaN is more chemical
stable and environmentally friendly than GaAs. GaN-based HEMT has a current
flow which is controlled by a metal Schottky-gate leads to a MOS structure on the
top of HEMT, which decreases gate leakage current in Schottky-gate devices and the
N.-T. Do · N.-H. Thoan · T. M. Quang · D. A. Tuan · N.-N. Trung (B )
School of Engineering Physics, Hanoi University of Scienceand Technology, Hanoi, Vietnam
e-mail: trung.nguyenngoc@hust.edu.vn
© Springer Nature Switzerland AG 2020
I. A. Parinov et al. (eds.), Advanced Materials, Springer Proceedings
in Materials 6, https://doi.org/10.1007/978-3-030-45120-2_39
477