Charge Balance Design of 1200-V E-Mode p-GaN Gate HEMT Toward Enhanced Breakdown Voltage and Dynamic Stability

This work investigates the charge balance design of the 1200-V E-mode lateral superjunction p-GaN gate HEMT (SJ-HEMT) on sapphire substrate. The charge balance is formed through the alternative p-/n-pillars; the p-pillars are thinned p-GaN stripes, and the n-pillars are 2DEG stripes. The charge balance design on the static and dynamic performance of the SJ-HEMT was investigated by tuning the width of p-/n-pillars. The SJ-HEMT with charge balance yields a BV of 2655 V and a high BV/<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${L}_{\text {GD}}$ </tex-math></inline-formula> ratio of 1.56 MV/cm. Notably, the SJ-HEMT demonstrates effective suppression of trapping effects, which exhibits a strong correlation with the gap between two p-pillars. At charge balance design, the SJ-HEMT presents an excellent dynamic <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${R}_{\text {ON}}$ </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">${R}_{\text {ON}}$ </tex-math></inline-formula> ratio of 1.28 under <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {DS}}$ </tex-math></inline-formula> stress up to 1200 V. Our study also indicates a scaling of p-/n-pillars can further improve 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">${R}_{\text {ON}}$ </tex-math></inline-formula> performance. This work underscores the merits of charge-balanced design for high-performance 1200-V E-mode GaN power transistors.