3C silicon carbide diode device structure on silicon substrate and preparation method thereof

The invention discloses a 3C silicon carbide diode device structure on a silicon substrate, which comprises a p-type lightly-doped silicon substrate, and an n-type highly-doped 3C silicon carbide epitaxial layer and an n-type doped 3C silicon carbide drift layer are sequentially arranged above the p-type lightly-doped silicon substrate. And a p-type junction region is arranged at the top of the 3C silicon carbide drift layer. The bottom of the p-type silicon substrate is provided with a groove structure, and the bottom of the groove extends to the n-type 3C silicon carbide epitaxial layer, so that the ohmic contact metal is in contact with the n-type 3C silicon carbide epitaxial layer. A silicon dioxide ILD structure is arranged above the n-type 3C silicon carbide drift layer, the middle of the silicon dioxide ILD structure is open, and Schottky contact metal and pad metal are sequentially filled in the silicon dioxide ILD structure. The pad metal is covered with a passivation layer, and a central opening of