Review of the Gate Structure for Normally Off p-GaN High-Electron-Mobility Transistors Towards High Performances

Area of Science:

• Materials Science
• Semiconductor Physics
• Power Electronics

Background:

• Gallium nitride (GaN) is a wide-bandgap semiconductor with superior properties for power electronics.
• AlGaN/GaN heterostructures are key for achieving normally off operation.
• p-GaN gate HEMTs are a focus for commercial power applications.

Purpose of the Study:

• To review the necessity of normally off operation in GaN HEMTs.
• To elaborate on the advantages and theory of p-GaN gates.
• To discuss various gate structures and optimization methods for p-GaN gate HEMTs.

Main Methods:

• Review of existing literature on p-GaN gate HEMTs.
• Analysis of different gate structures (metal, junction, hybrid) on the p-GaN layer.
• Discussion of fabrication processes and optimization strategies for threshold and breakdown voltage.

Main Results:

• p-GaN gates are crucial for achieving normally off operation in AlGaN/GaN HEMTs.
• Gate structure design significantly impacts threshold voltage.
• Optimization methods can enhance breakdown voltage and enable monolithic integration.

Conclusions:

• p-GaN gate HEMTs are vital for next-generation power systems.
• Further research into gate structures and fabrication is needed for improved performance.
• This technology holds promise for advanced power electronics.