Simulation Optimization of AlGaN/GaN SBD with Field Plate Structures and Recessed Anode

Area of Science:

• Materials Science
• Electrical Engineering
• Semiconductor Physics

Background:

• Aluminum Gallium Nitride/Gallium Nitride (AlGaN/GaN) heterostructures are crucial for high-power electronics.
• Schottky Barrier Diodes (SBDs) are essential components in power switching and high-frequency applications.
• Device optimization is key to unlocking the full potential of AlGaN/GaN SBDs.

Purpose of the Study:

• To optimize AlGaN/GaN SBDs through design modifications.
• To investigate the impact of electrode spacing, etching depth, and field plate size.
• To enhance device performance metrics like forward current and breakdown voltage.

Main Methods:

• Technology Computer-Aided Design (TCAD) simulations using Silvaco software for device design and analysis.
• Fabrication of AlGaN/GaN SBD chips based on simulation-derived parameters.
• Experimental characterization of electrical behavior, including forward current, on-resistance, and breakdown voltage.

Main Results:

• A recessed anode design was found to increase forward current and decrease on-resistance.
• An etching depth of 30 nm yielded a turn-on voltage of 0.75 V and a forward current density of 216 mA/mm.
• A 3 μm field plate achieved a breakdown voltage of 1043 V and a power figure of merit (FOM) of 572.6 MW/cm².

Conclusions:

• Recessed anode and field plate structures effectively boost breakdown voltage and forward current in AlGaN/GaN SBDs.
• Optimized device designs lead to significant improvements in the power figure of merit (FOM).
• Enhanced electrical performance broadens the application scope for these high-performance diodes.