Abstract: The present disclosure provides a split gate MOSFET and a manufacturing method thereof. An epitaxy layer with a first conductivity type is formed on a substrate. A plurality of trenches are formed in the epitaxy layer. Impurities with a second conductive type is implanted and driven to the trenches to form a plurality of first doping areas. Since the first doping areas and none-doping areas of the epitaxy layer are alternately arranged with each other, and the first conductive type and the second conductive type are different conductivity types selected from P type or N type, the split gate MOSFET including the super junction structure is manufactured, and the advantages of simplifying manufacturing process, reducing cost and greatly reducing the on-resistance are achieved.

Abstract: A manufacturing method of a gate structure includes steps of forming a mask oxide layer on the substrate, performing a photolithography process on the mask oxide layer and the substrate to form a trench, etching the trench, removing the mask oxide layer, forming a bottom oxide layer on a surface of the substrate and a trench surface of the trench, forming a silicon nitride layer on the trench, removing a part of the bottom oxide layer, removing the silicon nitride layer, forming a gate oxide layer on the surface and a part of the trench surface, and forming a poly layer on the trench. Therefore, the advantages of simplifying the gate structure process and reducing the production cost are achieved.

Abstract: A manufacturing method of a split gate structure includes steps of forming a mask oxide layer on the substrate, performing photolithography and etching on the mask oxide layer and the substrate, forming a trench, removing the mask oxide layer, forming a bottom oxide layer on a bottom part and a side wall of the trench and a surface of the substrate, forming a silicon nitride layer on the trench, removing a part of the bottom oxide layer, forming a gate oxide layer on part of the side wall and the surface, forming a gate poly layer on the trench, removing the silicon nitride layer, forming an inter-poly oxide layer on the gate poly layer, and forming a shield poly layer on the trench, thereby benefiting the increasing of the thickness of the inter-poly oxide layer, so that the advantages of improving the characteristics of the split gate structure are achieved.

Abstract: A manufacturing method of a gate structure includes steps of forming a mask oxide layer on the substrate, performing a photolithography process on the mask oxide layer and the substrate to form a trench, etching the trench, removing the mask oxide layer, forming a bottom oxide layer on a surface of the substrate and a trench surface of the trench, forming a silicon nitride layer on the trench, removing a part of the bottom oxide layer, removing the silicon nitride layer, forming a gate oxide layer on the surface and a part of the trench surface, and forming a poly layer on the trench. Therefore, the advantages of simplifying the gate structure process and reducing the production cost are achieved.

Abstract: A manufacturing method of a split gate structure includes steps of forming a mask oxide layer on the substrate, performing photolithography and etching on the mask oxide layer and the substrate, forming a trench, removing the mask oxide layer, forming a bottom oxide layer on a bottom part and a side wall of the trench and a surface of the substrate, forming a silicon nitride layer on the trench, removing a part of the bottom oxide layer, forming a gate oxide layer on part of the side wall and the surface, forming a gate poly layer on the trench, removing the silicon nitride layer, forming an inter-poly oxide layer on the gate poly layer, and forming a shield poly layer on the trench, thereby benefiting the increasing of the thickness of the inter-poly oxide layer, so that the advantages of improving the characteristics of the split gate structure are achieved.