Design and Simulation of a High-Performance GaN Vertical Merged P-i-N/Schottky (MPS) Diode with Multi-Drift-Layer and...

Area of Science:

• Power Electronics
• Semiconductor Devices
• Materials Science

Background:

• Gallium Nitride (GaN) vertical Merged P-i-N/Schottky (MPS) diodes are crucial for high-power applications.
• Conventional designs face trade-offs between on-resistance and breakdown voltage.
• Advanced doping profiles, passivation, and termination techniques are needed to enhance performance.

Purpose of the Study:

• To design, structurally optimize, and simulate a novel GaN vertical MPS diode.
• To investigate the impact of various parameters on diode performance metrics.
• To achieve superior performance metrics, including breakdown voltage and figure of merit.

Main Methods:

• Two-dimensional (2D) Technology Computer-Aided Design (TCAD) simulations were employed.
• Systematic simulations explored dependences on Schottky work function, doping, layer thickness, and contact ratio.
• Analysis included operating temperature and reverse recovery switching transients.

Main Results:

• The MPS architecture effectively decouples forward conduction loss from reverse blocking capability.
• Optimal doping and thickness achieved a Baliga's Figure of Merit (BFOM) of 55.36 GW·cm⁻² (BV = 6.61 kV, Ron = 0.79 mΩ·cm²), a 73% improvement.
• Positive breakdown voltage temperature coefficient and reduced reverse recovery charge (Qrr) were observed.

Conclusions:

• The proposed GaN vertical MPS diode design overcomes conventional R_on-BV trade-offs.
• The optimized device exhibits excellent performance suitable for demanding power electronic applications.
• The study highlights the potential for high-voltage, high-frequency, and high-temperature power systems.