An Improved 4H-SiC Trench Gate MOSFETs Structure with Low On-Resistance and Reduced Gate Charge

Abstract:

In this paper, an improved 4H-SiC trench-gate metal-oxide-semiconductor field effect transistors (UMOSFETs) structure with low on-resistance and reduced gate charge is proposed. The added n-type region in the improved structure reduces on-resistance of the device significantly while maintaining same breakdown voltage. The gate of the improved structure is designed as a p-n junction to reduce the gate-charge. The specific on-resistances of the improved 4H-SiC UMOSFETs is 1.87 mΩ.cm² at V_GS=18 V and V_DS=10 V, compared with 4.48 mΩ.cm² for the conventional p⁺ shielding UMOSFETs structure with same breakdown voltage. The on-resistance and figure of merit (FOM = V_BR²/R_on) improve by 58.3% and 103.6%, respectively. Compared with the conventional structure, the results show that gate-drain charge of the improved structure can be improved by 23.8%.

• Periodical: Materials Science Forum (Volume 954)
• Pages: 151-156
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.954.151
• Online since: May 2019
• Authors: Kai Tian, Jing Hua Xia, Jin Wei Qi, Shen Hui Ma, Fei Yang, Anping Zhang*
• Keywords: Breakdown Voltage, Figure-of-Merit, Gate-Drain Charge, Silicon Carbide, Specific On-Resistance, Trench-Gate MOSFETs

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