Influence of Trench Design on the Electrical Properties of 650V 4H-SiC JBS Diodes

Abstract:

This work presents a design study of customized p⁺ arrays having influence on the electrical properties of manufactured 4H-SiC Junction Barrier Schottky (JBS) diodes with designated electrical characteristics of 5 A forward and 650 V blocking capabilities. The effect of the Schottky area consuming p⁺ grid on the forward voltage drop, the leakage current and therefore the breakdown voltage was investigated. A recessed p⁺ implantation, realized through trench etching before implanting the bottom of the trenches, results in a more effective shielding of the electrical field at the Schottky interface and therefore reduces the leakage current. Customizing the p⁺ grid array in combination with the trench structure, various JBS diode variants with active areas of 1.69 mm² were fabricated whereas forward voltage drops of 1.58 V @ 5 A with blocking capabilities up to 1 kV were achieved.

• Periodical: Materials Science Forum (Volume 963)
• Pages: 549-552
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.963.549
• Online since: July 2019
• Authors: Oleg Rusch*, Jonathan Moult, Tobias Erlbacher
• Keywords: 4H-SiC, Design Study, Junction Barrier Schottky (JBS) Diode, Ohmic Contact, Schottky Barrier Lowering, Trench

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