Transistor and manufacturing method of terminal structure thereof

Abstract

The invention provides a transistor and a manufacturing method of a terminal structure thereof. The method includes the following steps: providing a substrate of a first conductivity type, forming anepitaxial layer of the first conductivity type on the upper surface of the substrate, forming a first trench on the upper surface of the epitaxial layer, forming a first oxide layer on the upper surface of the first trench, forming a gate oxide layer on the upper surfaces of the epitaxial layer and the first oxide layer, forming a polysilicon layer on the upper surface of the gate oxide layer, forming a plurality of second trenches on the polysilicon layer, forming a body region on the upper surface of the epitaxial layer, forming a second oxide layer on the upper surface of the polysilicon layer, forming a dielectric layer and a contact hole on the upper surface of the transistor, and forming a source metal layer on the upper surface of the dielectric layer. According to the scheme of theinvention, the source metal layer is connected with a low potential, the substrate is connected with a positive potential, and once the reverse bias potential difference is larger, a better inversionlayer is formed on the outer side of the polysilicon layer to counteract a strong electric field extending from the body region, and thus the withstand voltage performance of the device is realized.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a manufacturing method of a semiconductor transistor and a terminal structure thereof. Background technique [0002] The withstand voltage capability of a power device mainly depends on the reverse bias breakdown voltage of a specific PN junction in the device structure, and in order to obtain a certain current capability, a power device is usually composed of many cells connected in parallel. When the device reverses the withstand voltage, because the transverse electric field between the cells cancels each other, because the breakdown generally does not occur inside the cell, but the outermost cell will break down due to the concentration of the electric field, so A specific structure is required to reduce the electric field and thus increase the breakdown voltage. These special structures are called terminal technology. [0003] Junction terminals can be roughly divide...

AI Technical Summary

Problems solved by technology

Due to the large area of ​​the JTE junction terminal, for high-voltage devices, the longer the lateral length of the JTE structure, the larger the source-drain capacitance of the device will affect the operating frequency of the device.

In addition, the production of JTE structure will consume a lot of time

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