This work studies the avalanche characteristics of the 1.2 kV vertical GaN p-n diodes with implanted edge termination, based on quasi-static current-voltage (I-V) sweeps and unclamped inductive switching (UIS) tests. The UIS tests reveal a ~1.7 kV avalanche breakdown voltage ( $BV_{{\text {AVA}}}{)}$ , 51 A maximum avalanche current ( ${I}_{{\text {AVA}}}{)}$ , and 63 mJ maximum avalanche energy ( ${E}_{{\text {AVA}}}$ ). The ${I}_{{\text {AVA}}}$ and ${E}_{{\text {AVA}}}$ are the highest reported in high-voltage GaN power devices. A lower $BV_{{\text {AVA}}}$ is observed in the I-V curves and a trap mediated avalanche model is proposed to explain it. The $BV_{{\text {AVA}}}$ in I-V curves is believed to be induced by avalanche-assisted trap-filling in the edge termination region, while the $BV_{{\text {AVA}}}$ in the UIS test reflects the robust avalanche at the main p-n junction. These results provide important new insights on the avalanche breakdown in GaN devices and address some seemingly contrary observations of vertical GaN p-n diodes published recently.

中文翻译：

---

大面积 1.2 kV 垂直 GaN pn 二极管中的陷阱介导雪崩

本工作基于准静态电流-电压研究了 1.2 kV 垂直 GaN pn 二极管的雪崩特性，该二极管具有注入边缘终止（四) 扫描和非钳位感应开关 (UIS) 测试。UIS 测试显示 ~1.7 kV 雪崩击穿电压 ( $BV_{{\text {AVA}}}{)}$ , 51 A 最大雪崩电流 ( ${I}_{{\text {AVA}}}{)}$ , 和 63 mJ 最大雪崩能量 ( ${E}_{{\text {AVA}}}$ ）。这 ${I}_{{\text {AVA}}}$ 和 ${E}_{{\text {AVA}}}$ 是高压 GaN 功率器件中报道的最高值。一个较低的 $BV_{{\text {AVA}}}$ 在观察到 四曲线和陷阱介导的雪崩模型被提出来解释它。这 $BV_{{\text {AVA}}}$ 在 四 曲线被认为是由边缘终止区域中的雪崩辅助陷阱填充引起的，而 $BV_{{\text {AVA}}}$ 在 UIS 测试中反映了主 pn 结处的强大雪崩。这些结果为 GaN 器件中的雪崩击穿提供了重要的新见解，并解决了最近发表的垂直 GaN pn 二极管的一些看似相反的观察结果。