Improvement Performance of p-GaN Gate High-Electron-Mobility Transistors with GaN/AlN/AlGaN Barrier Structure

• Published in: Micromachines (Basel) Vol. 15; no. 4; p. 517
• Main Authors: Liu, An-Chen, Huang, Yu-Wen, Chen, Hsin-Chu, Kuo, Hao-Chung
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.04.2024
• Subjects: Aluminum gallium nitrides; Aluminum nitride; Barrier layers; Carrier density; Current leakage; Design; Design and construction; Diffusion barriers; Diffusion layers; Electrical properties; Energy gap; epitaxy; Gallium nitrides; gate leakage current; HEMT; High electron mobility transistors; Integrated circuit fabrication; Materials; Methods; p-GaN gate; Semiconductor devices; threshold voltage; Taiwan; p-GaN gate; gate leakage current; HEMT; threshold voltage; epitaxy
• ISSN: 2072-666X; 2072-666X
• DOI: 10.3390/mi15040517

This study demonstrates a particular composited barrier structure of high-electron-mobility transistors (HEMTs) with an enhancement mode composed of p-GaN/GaN/AlN/AlGaN/GaN. The purpose of the composite barrier structure device is to increase the maximum drain current, reduce gate leakage, and achieve lower on-resistance (Ron) performance. A comparison was made between the conventional device without the composited barrier and the device with the composited barrier structure. The maximum drain current is significantly increased by 37%, and Ron is significantly reduced by 23%, highlighting the synergistic impact of the composite barrier structure on device performance improvement. This reason can be attributed to the undoped GaN (u-GaN) barrier layer beneath p-GaN, which was introduced to mitigate Mg diffusion in the capping layer, thus addressing its negative effects. Furthermore, the AlN barrier layer exhibits enhanced electrical properties, which can be attributed to the critical role of high-energy-gap properties that increase the 2DEG carrier density and block leakage pathways. These traps impact the device behavior mechanism, and the simulation for a more in-depth analysis of how the composited barrier structure brings improvement is introduced using Synopsys Sentaurus TCAD.