High-Voltage E-Mode p-GaN Gate HEMT on Sapphire With Gate Termination Extension
Jiawei Cui, Yanlin Wu, Junjie Yang, Jingjing Yu, Teng Li, Xiaosen Liu, Kai Cheng, Xuelin Yang, Yilong Hao, Jinyan Wang, Bo Shen, Maojun Wang, Jin Wei
Abstract
An enhancement-mode (E-mode) p-type gallium nitride (p-GaN) gate high electron mobility transistor with a gate termination extension (GTE-HEMT) has been developed on a sapphire substrate, intended for power switching applications of kilovoltage (kV) level. The GTE-HEMT device exhibits a low ON-resistance ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${R} _{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> ) of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$19.3~\Omega \cdot $ </tex-math></inline-formula> mm, corresponding to a specific <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${R} _{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${R} _{ \mathrm{\scriptscriptstyle ON},\text {SP}}$ </tex-math></inline-formula> ) of 7.33 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{m}\Omega \cdot $ </tex-math></inline-formula> cm2. Notably, the GTE-HEMT has achieved a breakthrough by increasing the breakdown voltage (BV) to 2573 V, surpassing the conventional p-GaN gate HEMT (Conv-HEMT) with its BV of 1679 V. The enhanced BV is ascribed to the gate termination extension (GTE) that reduces the gate-edge electric field peak, similar to a junction termination extension (JTE) in traditional Si power devices. In addition, the dynamic <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${R} _{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> of the GTE-HEMT has been improved, with a normalized dynamic <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${R} _{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> (dynamic <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${R} _{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> /static <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${R} _{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> ) of 1.4 and 2.6 for 650- and 1200-V OFF-state stress, respectively. The GTE-HEMT has been benchmarked to the state-of-the-art GaN power transistors, demonstrating its potential for high-voltage applications.