Optimization Conditions for High-Power AlGaN/InGaN/GaN/AlGaN High-Electron-Mobility Transistor Grown on SiC...

Area of Science:

• Materials Science
• Semiconductor Physics
• Electrical Engineering

Background:

• High Electron Mobility Transistors (HEMTs) based on AlGaN/GaN heterostructures are crucial for high-power and high-frequency applications.
• Optimizing the device structure is essential for improving performance metrics like breakdown voltage and current handling.

Purpose of the Study:

• To determine the optimal structural parameters for AlGaN/InGaN/GaN/AlGaN/SiC HEMTs.
• To investigate the impact of InGaN layer thickness and composition on breakdown voltage and other device characteristics.

Main Methods:

• Simulations were performed to analyze the breakdown voltage of AlGaN/InGaN/GaN/AlGaN/SiC HEMTs.
• The study systematically varied the In composition and thickness of the InGaN layer.

Main Results:

• Breakdown voltage is highly sensitive to In composition, increasing significantly up to 0.06 and then saturating.
• Optimal In composition for high breakdown voltage is ≥0.06.
• Breakdown voltage is less affected by thickness, remaining stable until exceeding 10 nm, after which it decreases.
• Optimal InGaN thickness is <10 nm.
• Increased In composition positively impacts drain current but also raises subthreshold swing (SS).
• InGaN layer thickness has minimal effect on SS.

Conclusions:

• The study provides critical insights into optimizing AlGaN/InGaN/GaN/AlGaN/SiC HEMT structures.
• Maintaining In composition at or above 0.06 and thickness below 10 nm is recommended for superior breakdown voltage.
• Trade-offs between breakdown voltage, SS, and drain current must be considered during device design.