Liu Jianhua, Guo Yufeng, Zhang Jun, Yao Jiafei, Li Man, Zhang Maolin, Chen Jing, Huang Xiaoming, Huang Chenyang
College of Electronic and Optical Engineering and College of Microelectronics, Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology, Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
Micromachines (Basel). 2021 Oct 14;12(10):1244. doi: 10.3390/mi12101244.
The AlGaN/GaN high electron mobility transistor with a step-doped channel (SDC-HEMT) is first proposed in this paper. The potential distribution and the electric field (E-field) distribution of the device are explored by the numerical approach and analytical approach simultaneously. By introducing extra dopants to the channel layer, the E-field distribution along the AlGaN/GaN heterojunction interface is reshaped, resulting in an improved breakdown characteristic. An optimized doping concentration gradient of channel layer of 2 × 10 cm/step is proposed and verified by simulations. The breakdown voltage (BV) of the optimized SDC-HEMT reaches 1486 V with a 59.8% improvement compared with conventional AlGaN/GaN HEMT. In addition, the average E-field in the region between gate and drain improves from 1.5 to 2.5 MV/cm. Based on the equivalent potential method (EPM), an analytical model of the E-field and potential distribution is presented. The veracity and effectiveness of the proposed methodology is verified by the good agreement between the simulated and modeled results.
本文首次提出了具有阶梯掺杂沟道的氮化铝镓/氮化镓高电子迁移率晶体管（SDC-HEMT）。通过数值方法和解析方法同时研究了该器件的电势分布和电场（E场）分布。通过向沟道层引入额外的掺杂剂，重塑了沿氮化铝镓/氮化镓异质结界面的电场分布，从而改善了击穿特性。提出了沟道层优化的掺杂浓度梯度为2×10 cm/步，并通过模拟进行了验证。优化后的SDC-HEMT的击穿电压（BV）达到1486 V，与传统的氮化铝镓/氮化镓HEMT相比提高了59.8%。此外，栅极和漏极之间区域的平均电场从1.5 MV/cm提高到2.5 MV/cm。基于等效电势法（EPM），给出了电场和电势分布的解析模型。模拟结果与模型结果的良好一致性验证了所提方法的准确性和有效性。
