Gate structure of semiconductor device and manufacturing method therefor

Abstract

A gate structure of a semiconductor device, includes: a trench gate and a planar gate including a plurality of polysilicon structures () separated from each other; the gate structure of the semiconductor device further includes a well region () being adjacent to the trench gate and being disposed under the planar gate; a first conduction type doped region () being disposed in the well region () and including a plurality of regions separated from each other, wherein each region is disposed under adjacent polysilicon structures (), and respective regions are electrically connected to the planar gate; and a source () being disposed in the well region (); wherein the trench gate includes: a silicon oxide filler () including a side wall silicon oxide and a bottom silicon oxide; a control gate () being located over the trench gate, wherein a side wall of the control gate is enclosed by the side wall silicon oxide, and the control gate () is electrically-connected to the planar gate; a shield gate () having a single segment structure or a longitudinally arranged multiple segments structure; and an insulation silicon oxide () being filled between adjacent control gate and shield gate in vertical direction.