In this study, p-GaN HEMTs with an indium-tin-oxide (ITO) electrode fabricated on the two different Mg concentration, i.e., $1 \mathbf {\mathrm {\times }} 10 ^{19}$ cm ⁻³ and $8 \mathbf {\mathrm {\times }} 10 ^{19\,\,}$ cm ⁻³ ,in p-GaN layer are investigated for the first time under the forward gate bias to understand the stability of the forward gate bias breakdown and ${\mathrm {V}}_{TH}$ shift stability. First of all, a Mg concentration in p-GaN layer results in a better Ohmic characteristic between the ITO and p-GaN contact. Furthermore, the fabricated device with a high Mg concentration of p-GaN layer shows a better forward gate breakdown voltage, which can be attributed to the better Ohmic characteristic between p-GaN and ITO electrode. Last, an obvious negative ${\mathrm {V}}_{TH}$ shift is observed, which is most probably related to the hole injections/trapping effects. In sum, the gate breakdown characteristic in p-GaN HEMTs with ITO electrode can be further improved while using high Mg concentration of p-GaN layer while an obvious a negative ${\mathrm {V}}_{TH}$ shift under a forward gate bias is observed, indicating a trade-off between the gate breakdown voltage and ${\mathrm {V}}_{TH}$ instability needs to be carefully considered to optimize the forward gate bias stability in p-GaN HEMTs with an ITO electrode.

中文翻译：

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在正向栅极偏置下具有铟锡氧化物栅极的 p-GaN HEMT 的稳定性研究

在这项研究中，p-GaN HEMTs 与氧化铟锡 (ITO) 电极在两种不同的镁浓度上制造，即， $1 \mathbf {\mathrm {\times }} 10 ^{19}$ cm ^-3和 $8 \mathbf {\mathrm {\times }} 10 ^{19\,\,}$ cm ^-3 , 在 p-GaN 层中首次在正向栅极偏压下进行研究，以了解正向栅极偏压击穿的稳定性和 ${\mathrm {V}}_{TH}$ 换档稳定性。首先，p-GaN层中的Mg浓度导致ITO和p-GaN接触之间更好的欧姆特性。此外，具有高 Mg 浓度 p-GaN 层的制造器件显示出更好的正向栅极击穿电压，这可归因于 p-GaN 和 ITO 电极之间更好的欧姆特性。最后，一个明显的负面 ${\mathrm {V}}_{TH}$ 观察到偏移，这很可能与空穴注入/捕获效应有关。总之，在使用高镁浓度的 p-GaN 层的同时，具有 ITO 电极的 p-GaN HEMT 的栅极击穿特性可以进一步提高，而明显的负 ${\mathrm {V}}_{TH}$ 观察到正向栅极偏置下的偏移，表明栅极击穿电压和 ${\mathrm {V}}_{TH}$ 需要仔细考虑不稳定性，以优化具有 ITO 电极的 p-GaN HEMT 的正向栅极偏置稳定性。