Trench type metal-oxide semiconductor device and manufacture method thereof

Abstract

The invention relates to a manufacture method of a trench type metal-oxide semiconductor device. On a grid dielectric layer, a first polycrystalline silicon layer is deposited along the inner wall of a grid trench. Then, a first conductivity type dopant is implanted to the first polycrystalline silicon layer located at the bottom of the grid trench. Subsequently, a second polycrystalline silicon layer doped with a second conductivity type dopant is deposited to cover the first polycrystalline silicon layer. Subsequently, a high-temperature process is applied to enable the dopants in the firstpolycrystalline silicon layer and the second polycrystalline silicon layer to diffuse, and thereby, a first conductivity type first doping area and a second conductivity type second doping area whichare arranged at the bottom of the grid trench are formed.

Description

technical field [0001] The invention relates to a trench type metal oxide semiconductor element and a manufacturing method thereof, in particular to a trench type metal oxide semiconductor element with low gate capacitance (Cgd) and a manufacturing method thereof. Background technique [0002] Compared with the traditional planar metal oxide semiconductor device, the current direction is along the direction parallel to the surface of the substrate, and the trench metal oxide semiconductor device sets the gate in the channel, changing the channel of the metal oxide semiconductor device position, so that the current direction of the metal oxide semiconductor device is perpendicular to the substrate. Therefore, the size of the element can be reduced, the activeness of the element can be improved, and the manufacturing cost can be reduced. Common metal oxide semiconductor devices on the market include metal oxide semiconductor field effect transistors (MOSFETs), insulated gate ...

AI Technical Summary

Problems solved by technology

However, in order to reduce the capacitance value from the gate to the drain of the metal oxide semiconductor device, the complexity of the process of the metal oxide semiconductor device is often greatly increased, resulting in an increase in the production cost.

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