In this paper, we investigate the charge trapping in power AlGaN/GaN high electron mobility transistors which occurs in ON-state operation (V _DS = 40 V, V _GS = 0 V, I _DS = 0.18 A mm⁻¹). By analysing the dynamic ON-resistance (R _ON) after OFF-state and ON-state stress in devices with different SiN _x passivation stoichiometries, we find that this charge trapping can be largely suppressed by a high Si concentration passivation. Both potential probe and electroluminescence (EL) measurements further confirm that the stress can induce negative charge trapping in the gate–drain access region. It is shown that EL is generated as expected under the field plates at the gate edge, but is obscured by the field plates and is actually emitted from the device near the drain edge; hence care is required when using EL alone as a guide to the location of the high field region in the device. From temperature-dependent dynamic R _ON transient measurements, we determine that the apparent activation energy of the measured ‘trap’ response is around 0.48 eV, and infer that they are located in the heavily carbon-doped GaN layer. Using the leaky dielectric model, we explain the response in terms of the hopping transport from the same substitutional carbon acceptor buffer dopants.

在本文中，我们研究了功率 AlGaN/GaN 高电子迁移率晶体管在导通状态下发生的电荷俘获（V _DS = 40 V，V _GS = 0 V，I _DS = 0.18 A mm ^-1）。通过分析不同 SiN _x器件在关断和导通应力后的动态导通电阻 ( R _ON ) 通过钝化化学计量，我们发现这种电荷俘获可以在很大程度上被高 Si 浓度钝化抑制。电位探针和电致发光 (EL) 测量进一步证实，应力可以在栅极 - 漏极存取区域中引起负电荷俘获。结果表明，EL 在栅极边缘的场板下方按预期产生，但被场板遮挡，实际上是从靠近漏极边缘的器件发射的；因此，单独使用 EL 作为设备中高场区位置的指南时需要小心。从依赖于温度的动态- [R _ON在瞬态测量中，我们确定测得的“陷阱”响应的表观活化能约为 0.48 eV，并推断它们位于重碳掺杂的 GaN 层中。使用泄漏电介质模型，我们根据来自相同替代碳受体缓冲掺杂剂的跳跃传输来解释响应。