Nitrogen-Implanted Guard Rings for 600-V Quasi-Vertical GaN-on-Si Schottky Barrier Diodes With a BFOM of 0.26 GW/cm<sup>2</sup>
Xiaolu Guo, Yaozong Zhong, Yu Zhou, S. S. Su, Xin Chen, Shumeng Yan, Jianxun Liu, Xiujian Sun, Qian Sun, Hui Yang
Abstract
This work demonstrates a novel Nitrogen-implanted (N-implanted) guard ring (GR) technology for the 600-V quasi-vertical GaN-on-Si Schottky barrier diode (SBD). The GR parameters are designed and studied in detail by the TCAD simulation. With a 4.4- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> -thick GaN drift layer, seven GRs with a precise design greatly enhance the breakdown voltage of GaN SBDs from ~290 to ~600 V, and barely degrade the ON-state characteristics, including 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">${I}_{ {\scriptscriptstyle { \mathrm {ON}}}}/{I}_{ {\scriptscriptstyle { \mathrm {OFF}}}}$ </tex-math></inline-formula> of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sup> , a low ideality factor of 1.06, a low turn-on voltage of 0.64 V (at 1 A/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ), and a low-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">${R}_{ {\scriptscriptstyle { \mathrm {ON}}},{\mathrm {sp}}}$ </tex-math></inline-formula> ) of 1.40 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{m}\Omega ~\cdot ~{\mathrm {cm}}^{2}$ </tex-math></inline-formula> , leading to a record Baliga’s figure of merit (BFOM) of 0.26 GW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> among all the reported vertical GaN-on-Si SBDs. At 175 °C, the SBD with seven GRs shows a slightly increased <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${R}_{ {\scriptscriptstyle { \mathrm {ON}}},{\mathrm {sp}}}$ </tex-math></inline-formula> of 1.86 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{m}\Omega ~\cdot ~{\mathrm {cm}}^{2}$ </tex-math></inline-formula> and an excellent electrical characteristic even under a reverse bias of 380 V, implying a high-temperature operation capability of N-implanted GRs.