Power device and manufacturing method thereof

A manufacturing method for a power device, comprising steps:

• S100:
• growing an epitaxial layer on a substrate;
• S200:
• dividing a gate contact region, an active region, a termination region, and a termination peripheral region along a horizontal direction, forming gate interconnection structures in the gate contact region, forming trench gates in the active region, and forming voltage-withstanding rings and at least one field ring in the termination region;
• S300:
• forming a first implantation region in an upper portion of the epitaxial layer by ion implantation, wherein a thickness of the first implantation region is less than a depth of the at least one field ring, and a portion of the first implantation region within the gate contact region and the active region form a body region;
• S400:
• forming a source region on one side of each of the trench gates by ion implantation;
• S500:
• depositing an isolation layer on the epitaxial layer, and manufacturing gate interconnection contacts, source contacts, field ring contacts, and drain contacts that extend through the isolation layer;
• wherein the gate interconnection contacts are respectively connected to the gate interconnection structures, each of the source contacts is connected to a corresponding source region, one of the field ring contacts is connected to the at least one field ring, and the drain contacts are connected to a portion of the first implantation region within the termination peripheral region;
• and
• S600:
• performing metallization deposition on the isolation layer, and forming a gate metal, a source metal, a field ring metal, and a drain metal that are isolated from each other by photolithography and etching;
• wherein the gate metal is connected to the gate interconnection contacts, the source metal is connected to the source contacts, the field ring metal is connected to the field ring contacts, and the drain metal is connected to the drain contacts.