Vertical GaN Schottky Barrier Diode With Record High Figure of Merit (1.1 GW/cm<sup>2</sup>) Fully Grown by Hydride Vapor Phase Epitaxy
Xinke Liu, Ping Zou, Haofan Wang, Yuheng Lin, Junye Wu, Zengfa Chen, Xinzhong Wang, Shuangwu Huang
Abstract
Vertical GaN-on-GaN Schottky barrier diode (SBD) fully grown by hydride vapor phase epitaxy (HVPE) was first demonstrated in this article. Due to the low-carbon impurity concentration grown by HVPE, the field effective mobility has been increased from 734 to 1188 cm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{{2}}\cdot \text{V}^{-{1}}\cdot \text{s}^{-{1}}$ </tex-math></inline-formula> . The fabricated device with this technology shows a low turn-on voltage of 0.52 V and a high <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ </tex-math></inline-formula> ratio of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$7.1\times 10^{{9}}$ </tex-math></inline-formula> . The specific 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> was 1.69 <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> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> at the current density of 500 A/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . High breakdown voltage <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {BR}}$ </tex-math></inline-formula> of 1370 V was achieved using He implantation technology. Among the reported vertical GaN SBDs with an indicated anode size, the highest figure of merit (FOM) ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {BR}}^{{2}}/{R}_{ \mathrm{\scriptscriptstyle ON}}{)}$ </tex-math></inline-formula> of 1.1 GW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> has been achieved to date.