Abstract: A trench-gate field effect transistor includes a plurality of trenches, a plurality of gate electrode units, and a plurality of source electrode units. Each of the trenches has a first trench region, a second trench region having a width less than that of the first trench region, and a neck trench region extending between the first trench region and the second trench region. Each of the gate electrode units includes a pair of first gate electrode portions disposed in the first trench region, a pair of second gate electrode portions disposed in the neck trench region, and a third gate electrode portion disposed in the second trench region. Each of the source electrode units includes a first source electrode portion disposed between a pair of the first gate electrode portions, and a second source electrode portion connected to the first source electrode portion.

Abstract: A fabricating method of a shielded gate MOSFET is provided, includes the steps of forming a semiconductor substrate having a trench, forming a sacrifice oxide layer in the trench, the sacrifice oxide layer covering a side wall of the trench, forming a source polycrystalline silicon region in the trench, forming an insulation oxide layer above the source polycrystalline silicon region to have the source polycrystalline silicon region fully enclosed by the sacrifice oxide layer and the insulation oxide layer, depositing polycrystalline silicon into the trench and carrying out a back etching to control a thickness of the insulation oxide layer above the source polycrystalline silicon region, forming a gate oxide layer in the trench, the gate oxide layer covering the side wall of the trench, forming a gate polycrystalline silicon region in the trench, and forming a body layer and a heavily doped region around the trench in an ion implantation manner.

Abstract: A fabricating method of a shielded gate MOSFET is provided, including steps of: forming a semiconductor substrate having a trench; forming a sacrifice oxide layer in the trench, the sacrifice oxide layer covering a side wall of the trench; forming a source polycrystalline silicon region in the trench; forming an insulation oxide layer above the source polycrystalline silicon region to have the source polycrystalline silicon region fully enclosed by the sacrifice oxide layer and the insulation oxide layer; depositing polycrystalline silicon into the trench and carrying out a back etching to control a thickness of the insulation oxide layer above the source polycrystalline silicon region; forming a gate oxide layer in the trench, the gate oxide layer covering the side wall of the trench; forming a gate polycrystalline silicon region in the trench; and forming a body layer and a heavily doped region around the trench in an ion implantation manner.