A Si/SiC Heterojunction Double-Trench MOSFET with Improved Conduction Characteristics

Area of Science:

• Materials Science
• Electrical Engineering
• Semiconductor Physics

Background:

• Conventional Silicon Carbide (SiC) devices face challenges with parasitic elements and conduction losses.
• Improving both forward and reverse conduction in high-voltage power devices is critical for efficiency and reliability.

Purpose of the Study:

• To propose and analyze a Si/SiC heterojunction double-trench Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) with enhanced conduction characteristics.
• To investigate the impact of Si/SiC heterojunction and high-k dielectric on device performance.

Main Methods:

• Utilized Technology Computer-Aided Design (TCAD) simulations to model and evaluate the proposed Si/SiC heterojunction MOSFET.
• Incorporated a high-k gate dielectric and a double-trench structure for performance optimization.

Main Results:

• Achieved a specific on-resistance (R_on,sp) of 1.78 mΩ·cm², a 20.5% reduction compared to conventional SiC DTMOS.
• Reduced third-quadrant turn-on voltage (V_on) from 2.74 V to 1.53 V, suppressing bipolar degradation.
• Maintained a comparable breakdown voltage (BV) of approximately 1380 V.

Conclusions:

• The proposed Si/SiC heterojunction MOSFET effectively improves both forward and reverse conduction characteristics.
• The device design mitigates parasitic PiN diode effects and enhances unipolar conduction, offering a promising solution for high-voltage power electronics.