A semiconductor device and a manufacturing method thereof

Abstract

The invention provides a semiconductor device and a manufacturing method thereof. The semiconductor manufacturing method comprises the following steps of: providing a first substrate; forming a firstwell region on a surface of the first substrate; forming a second well region in the first well region; Providing a second substrate having the same conductivity type as the first substrate; Forming athird well region on the surface of the second substrate; Bonding a surface of the first substrate that does not form a well and a surface of the second substrate that does not form a well. The device formed by the method can realize high-voltage reverse voltage withstand, and the manufacturing process is compatible with the traditional IGBT manufacturing process, the process is simple, the implementability is strong, and the problems of the prior art such as difficulty in manufacturing the high-voltage reverse resistance IGBT, high cost and the like are overcome.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a semiconductor device and a manufacturing method thereof. Background technique [0002] Semiconductor devices with bidirectional blocking capability are mainly represented by IGBT (Insulated Gate Bipolar Transistor), also known as insulated gate bipolar transistor. The reverse blocking IGBT (Reverse Blocking IGBT, RB-IGBT) is a new type of IGBT device evolved on the basis of the traditional punch-through IGBT. Compared with the traditional IGBT, the reverse blocking IGBT has reverse blocking ability. Both forward and reverse can withstand voltage, and are widely used in matrix converters, neutral point clamp topologies and T-type converters. [0003] attached figure 1 It is a common RB-IGBT structure, and the existing RB-IGBT manufacturing process is (attached figure 1 RB-IGBT as an example): [0004] Epitaxial N- epitaxial layer 2 with a certain thicknes...

AI Technical Summary

Problems solved by technology

However, for diffusion isolation, the depth of diffusion is proportional to the square root of time, so a large thermal budget is required (200um depth needs to be diffused for about 1 week), which is unrealistic for high-voltage devices, and due to lateral diffusion increases chip The size of the chip will cause a waste of chip area

It is very difficult to achieve high aspect ratio etching and sidewall ion implantation for trench isolation; and as the voltage level increases, the n-drift region becomes thicker and the process becomes more difficult

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