SiC Schottky power diode and production method thereof

Abstract

The invention discloses a SiC Schottky power diode. The SiC Schottky power diode comprises an N-type 4H-SiC substrate, a P-type 4H-SiC isolation layer and an N-type 4H-SiC epitaxial layer from bottom to top, and the thickness of the epitaxial layer is less than 6 microns; cathode ohmic contact metal is included and positioned on two sides of the upper surface of the epitaxial layer, and an N + injection region is arranged on the epitaxial layer below the cathode ohmic contact metal; an inverted trapezoidal anode groove is included and p + injection protection regions are arranged on the epitaxial layer around the four inner corners of the inverted trapezoidal anode groove; a passivation layer is included, the first part of the passivation layer is deposited on the upper surface, which is not etched and not covered by the cathode ohmic contact metal, of the epitaxial layer, and the second part of the passivation layer is deposited in the middle of the bottom of the inverted trapezoidal anode groove; and the inverted trapezoidal anode groove, the first portion of the passivation layer, and the second portion of the passivation layer cover the anode Schottky contact metal. According to the invention, the productization of the 4H-SiC Schottky power diode with the high voltage of more than 3000V is realized.

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 epitaxy process is not enough to support the productization of devices, thus limiting the commercialization of high-voltage 4H-SiC Schottky power diodes above 3000V

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