CAJ | 학술논문

通过实验测量对AlGaN/GaN HEMT表面钝化抑制电流崩塌的机理进行了深入研究.AlGaN/GaN HEMT Si3N4钝化层使用PECVD获得.文章综合考虑了钝化前后器件输出特性及泄漏电流的变化,钝化后直流电流崩塌明显减少,仍然存在小的崩塌是由于GaN缓冲层中的陷阱对电子的捕获.传输线模型测量表明,钝化后电流的增加是由于钝化消除了表面态密度进而增加了沟道载流子密度.
통과실험측량대AlGaN/GaN HEMT표면둔화억제전류붕탑적궤리진행료심입연구.AlGaN/GaN HEMT Si3N4둔화층사용PECVD획득.문장종합고필료둔화전후기건수출특성급설루전류적변화,둔화후직류전류붕탑명현감소,잉연존재소적붕탑시유우GaN완충층중적함정대전자적포획.전수선모형측량표명,둔화후전류적증가시유우둔화소제료표면태밀도진이증가료구도재류자밀도.
The effects of surface passivation on AlGaN/GaN high-electron-mobility transistors (HEMTs) have been investigated. The surface passivation layer of Si3N4 is deposited by plasma enhanced chemical vapor deposition (PECVD). The current-voltage and gate-drain diode characteristics of AlGaN/GaN HEMTs before and after passivation are analyzed. The current collapse under DC sweep has been significantly decreased after passivation and the existence of small dispersion of drain current is due to traps in the GaN buffer. The drain current increases after passivation, because surface passivation reduces the surface state density and so increases the sheet carrier density shown in Transmission Linear Model (TLM) measurement.