SiC Schottky power diode and production method thereof

Abstract

The invention discloses a SiC Schottky power diode which comprises a substrate, an isolation layer and an epitaxial layer. A cathode groove is engraved in the middle of the first region of the epitaxial layer, and an N + injection region is formed on the surface of the second region and the cathode groove; two P + injection regions are formed on the epitaxial layer at two sides of the cathode groove, a first passivation layer is covered on one P + injection region, a second passivation layer is partially covered on the other P + injection region, and an anode ohmic contact metal layer is partially covered on the other P + injection region; a cathode ohmic contact metal layer covers right above the N + injection region and fills the cathode groove; an anode schottky metal layer is stacked at the uppermost part of the first region, is electrically connected with the anode ohmic contact metal layer, and forms a PIN structure together with the two P + injection regions; and an intermediate medium is arranged between the cathode ohmic contact metal layer and the anode Schottky metal layer. According to the invention, the performance and yield of the 4H-SiC Schottky power diode under a high working voltage are improved.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, and in particular relates to a SiC Schottky power diode and a preparation method thereof. Background technique [0002] The common crystal types of SiC (silicon carbide) are 3C, 4H and 6H. Among them, 4H-SiC is the best choice for manufacturing power electronic power devices because of its good quality and low price. [0003] 4H-SiC Schottky power diodes are suitable for power systems such as rectification and inverters, and are one of the indispensable new power components in energy conversion systems for new industries such as electric vehicles, industrial control, and high-speed rail. With the continuous improvement of power capacity, the operating voltage and operating current of 4H-SiC Schottky power diodes will also be further increased. [0004] In the existing 4H-SiC power Schottky power diodes, in order to achieve higher operating voltage (greater than 3000V), most of them are a...

AI Technical Summary

Problems solved by technology

However, when the thickness of the epitaxial layer is greater than 20 μm, the SiC epitaxial process will greatly reduce the performance and yield of the 4H-SiC Schottky power diode, which is not conducive to the productization of the device

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