Proton-Irradiation Effects and Reliability on GaN-Based MIS-HEMTs.

Area of Science:

• Materials Science
• Semiconductor Device Physics
• Radiation Effects

Background:

• High Electron Mobility Transistors (HEMTs) are crucial for high-frequency applications.
• Proton irradiation can degrade semiconductor device performance.
• Dielectric layers in HEMTs significantly influence device reliability.

Purpose of the Study:

• To evaluate the proton irradiation reliability of a bilayer dielectric (SiNx/Al2O3) MIS-HEMT.
• To compare its performance against Schottky gate HEMTs and single dielectric layer MIS-HEMTs.
• To determine the impact of dielectric choice on material and electrical degradation under proton irradiation.

Main Methods:

• Device simulations to assess material defect generation.
• Experimental and simulation-based analysis of DC and RF electrical performance.
• Comparative study of four HEMT structures under proton irradiation.

Main Results:

• Bilayer dielectric MIS-HEMTs exhibited the least structural material degradation and fewest irradiation-induced defects.
• These devices showed the smallest threshold voltage, on-current, and transconductance (Gm) degradation rates.
• The bilayer structure maintained the highest cut-off frequency and demonstrated the lowest degradation in this parameter.

Conclusions:

• The SiNx/Al2O3 bilayer dielectric MIS-HEMT demonstrates superior radiation resilience compared to other structures.
• The combination of Al2O3's high displacement energy and SiNx's passivation properties enhances proton irradiation reliability.
• Bilayer dielectric HEMTs are a promising solution for radiation-hardened electronic devices.