| 摘要 |
Provided are a trench-type DMOS device and a manufacturing method thereof. The DMOS device comprises: a substrate (100) used as a public drain region, an active region (102) and a voltage-dividing ring (103) formed on the substrate (100), and a first dielectric layer (110) formed on the substrate (100). Multiple trenches are disposed on the first dielectric layer (110), and the trenches extend from the surface of the first dielectric layer (110) into the interior of the substrate (100). The trenches comprise at least one first trench (141) distributed in the active region (102) and a second trench (142) outside the active region (102). A gate oxide layer (144) is formed in the trench and polysilicon (143) is filled to form a gate. The active region (102) further comprises a source region (104) and a P-type heavily doped region (105) under the source region (104). A second dielectric layer (120) covers the first dielectric layer (110) and the multiple trenches. A metal layer (130) covers the second dielectric layer (120) to form a first electrode region (131) and a second electrode region (132). By increasing the cross-sectional area of the polysilicon (143) in the gate, the resistance of the gate is reduced. |
