MOS type fast recovery diode chip structure and manufacturing method thereof

The invention discloses an MOS type fast recovery diode chip structure and a manufacturing method thereof. An N-drift region is arranged on a heavily doped N + substrate, a P region is arranged in an active region on the N-drift region, an N + region is arranged on the P region, the N + region and P + short-circuit points are optionally arranged on the P region, the P + short-circuit points are uniformly arranged in the N + region, and the depth of the P + short-circuit points exceeds that of N +; longitudinal grooves parallel to each other are formed in the surface layer of an active region, the grooves penetrate through an N + layer on the surface layer of the active region and a P layer below the N + layer and then reach an N-layer of a drift region, doped heavy metal such as gold or platinum is distributed in an N-superficial area on the lower side of the bottom of each groove, silicon dioxide and polycrystalline silicon are filled in the grooves, and the bottom of the polycrystalline silicon exceeds the