Improved T _MAX Estimation in GaN HEMTs Using an Equivalent Hot Point Approximation

Abstract

In this article, heat generation distribution and maximum device temperature of gallium-nitride (GaN) high-electron-mobility transistors (HEMTs) are investigated by using the 2-D electrothermal and finite-element method (FEM) simulations. Devices with different gate lengths and source-to-drain spacing are investigated. It is observed that the maximum device temperature (T MAX) depends on the drain-to-source spacing and is almost independent of the gate length and that the assumption of a uniform heat generation region, under the gate, is not accurate; this is contrary to conventional calculation methods. Moreover, based on the results, a new approximation is proposed to use in the FEM simulations that can estimate T MAX more accurately. This method does not require physics-based technology computer-aided design (TCAD) simulations and can work with a low mesh density. The performance is compared with prior methods. Index Terms-2-D device simulations, AlGaN, channel temperature, finite-element analysis, gallium nitride (GaN), high-electron-mobility transistors (HEMTs), hot point, selfheating, technology computer-aided design (TCAD), thermal analysis, thermal resistance. I. INTRODUCTION G ALLIUM-NITRIDE (GaN)-based high-electronmobility transistors (HEMTs) are high-performance devices that show superior performance in high-power amplifiers and switching applications [1]-[3]. The high bandgap leads to an elevated breakdown voltage [4]. The 2-D electron gas (2DEG) provides excellent electron mobility Manuscript

Design optimization of nanoscale electrothermal transport in 10 nm SOI FinFET technology node

“…Direct experimental predictions of thermal response in nanotransistors are not yet feasible. In order to analyze the performance of the 10 nm SOI FinFET, we use the FEM for thermal imaging and surface temperature detection [10,29]. The thermal properties of silicon (Si), SiO 2 and HfO 2 are extracted from [3,4].…”

“…For next-generation transistors, channel length in SOI FinFETs will be reduced to 6 nm for a long time (2026). In fact, the aggressive scaling down of nanodevices leads to high thermal resistance and low carrier mobility, which can influence the thermal stability [4,[8][9][10]. Several new technologies have emerged such as nanowires [11], tunnel FETs [12], and FinFET architectures [13].…”

“…Therefore, both the electrical and thermal behavior need to be correlated with the joule heating term. To solve these coupled phenomena, the finite element method (FEM) was used to capture the electrothermal transport in semiconductor devices [3,10].…”

Fast Unveiling of T max in GaN HEMT Devices via the Electrical Measurement-Assisted Two-Heat Source Model

“…Temperature-dependent nonlinearity on the channel resistance and the knee voltage is included in the TCAD simulations with the electron mobility modeling approach, according to the work of Farahmand et al [29]. Further details on the TCAD simulation conditions and the implementations be found in the recent publications [10], [11] of our research group. The values of most geometric parameters of the device are presented within the 3-D and 2-D illustrations in Fig.…”

Correlation-based study of FEA and IR thermography to reveal the 2DEG temperature of a multi-fingered high-power GaN HEMT

“…High-electron mobility transistors (HEMTs) based on gallium nitride (GaN) are attracting the attention of researchers day by day with the extensive advantages that they offer in a broad range of applications, such as high-power amplifiers, monolithic microwave integrated circuits (MMICs), high-performance radars, advanced satellite and space systems, emerging 5G and 6G communication, and digital and quantum computing electronics. [1][2][3][4][5][6][7][8] The main features that make GaN HEMTs so advantageous are [9][10][11][12] (i) high current capacity resulting from the higher electron mobility and the saturation velocity due to the two-dimensional electron gas (2DEG) confinement at the heterostructure, (ii) resistance to the high voltages owing to the wide bandgap of the semiconductor material, (iii) operation at high frequencies in the GHz and THz ranges, and (iv) processing high powers 13 thanks to the high current and the high voltage characteristics. GaN HEMT devices mostly operate at high power densities.…”