Super-junction device

Abstract

The present invention discloses a super-junction device. The super-junction device comprises an epitaxial layer, a plurality of surface structures and an isolation region; a super-junction structure is arranged in the epitaxial layer; the super-junction structure is composed of a plurality of first doped upright columns and a plurality of second doped upright columns which are alternately arranged; the doping type of the first doped upright columns is different from the doping type of the second doped upright columns; each of the plurality of surface structures comprises a first doped well region and a second doped well region arranged in the first doped well region; the doping type of the first doped well region is different from the doping type of the second doped well region; the isolation region is arranged between the first doped upright columns of the super-junction structure and the first doped well regions; the doping type of the first doped upright columns is same with the doping type of the first doped well regions; and the doping type of the isolation region is the same with the doping type of the second doped upright columns. The invention aims to solve the technical problem of long consumed time of the reverse recovery of a super-junction VDMOS in the prior art. The reverse recovery charge Qrr of the super-junction device can be greatly decreased, and the reverse recovery characteristic of the device can be improved.

Description

technical field [0001] The invention relates to the field of semiconductors, in particular to a super junction device. Background technique [0002] In the field of power semiconductors, a vertical metal oxide semiconductor field effect transistor (Metal Oxide Semiconductor Field Effect Transistor, MOSFET) formed by a vertical double diffusion process is called a VDMOSFET, or VDMOS for short. Such as figure 1 As shown, the withstand voltage layer of VDMOS is composed of a lightly doped epitaxial drift region, and the electric field is approximately trapezoidal in distribution, and the area surrounded by the electric field is the breakdown voltage (BV). Increasing the BV requires increasing the thickness of the drift region and reducing the doping concentration of the drift region, which will lead to an increase in the on-resistance Ron and greatly increase power consumption. There is a restrictive relationship between BV and Ron, which is called the silicon limit. Since t...

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Problems solved by technology

[0008] By providing a super-junction device, the present invention solves the technical problem that the super-junction VDMOS in the prior art takes a long time for reverse recovery of the device

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