SiC DMOSFET device integrated with HJD and preparation method thereof

The invention discloses a SiC DMOSFET device integrated with an HJD and a preparation method of the SiC DMOSFET device. The SiC DMOSFET device comprises a metalized drain electrode, an N + substrate region and an N-epitaxial region which are sequentially arranged in a stacked mode from bottom to top. The first P-base region and the second P-base region are arranged in the N-epitaxial region; the first P + injection region and the fourth P + injection region are respectively arranged in the first P-base region and the second P-base region, and the second P + injection region and the third P + injection region are arranged in the N-epitaxial region; the first N + injection region and the second N + injection region are respectively arranged in the first P-base region and the second P-base region; the N-PolySi region is arranged on the N-epitaxial region between the second P + injection region and the third P + injection region; the first N-PolySi grid electrode and the second N-PolySi grid electrode are respect