Novel high-current-density fast recovery diode structure and manufacturing method thereof

Abstract

The invention discloses a novel high-current-density fast recovery diode structure and a manufacturing method thereof, is applicable to the production of large-current fast recovery diodes, and belongs to the field of semiconductor devices. The method is characterized in that the grooving technology is used, grooves are formed in the active area on the front side of a chip, groove intervals are correspondingly adjusted according to device performance parameters, boron-doped polycrystalline silicon is then used for deposition, and a device grooved anode area is formed through pushing; a method using vacuum platinum steaming before annealing is used on the back of a single chip, and good central fast recovery feature is achieved; a terminal area is consistent with a conventional device and adopts a field ring structure; compared with the prior art, the novel high-current-density fast recovery diode structure can evidently increase device current density in unit chip area and increase device current capacity; the device active area of devices with identical current indexes can be effectively reduced, wafer utilization rate is increased, and economic benefits are increased; the heavily-doped polycrystalline silicon can be in ohmic contact with an N-type chip, and device reliability is increased.

Description

technical field [0001] The invention relates to a novel high current density fast recovery diode structure and its manufacturing method, which belongs to the technical field of power semiconductor devices. Background technique [0002] Fast recovery diodes are widely used in pulse width modulators, switching power supplies, uninterruptible power supplies, etc. In the device, it is used for high-frequency, high-voltage, high-current rectification, freewheeling and protection, and has become an indispensable part of the application device. [0003] The research and development of power semiconductor devices has led to the continuous development of fast recovery diodes in the direction of large capacity, high frequency, high efficiency, high reliability and lower cost. [0004] In the manufacture of fast recovery diodes, the method to reduce the reverse recovery time is to introduce recombination centers inside the device. Currently widely used technical means are light ion i...

AI Technical Summary

Problems solved by technology

[0006] The technical problem solved by the present invention is: to overcome the deficiencies of the existing technology, to provide a new type of high current density fast recovery diode structure and its manufacturing method, by digging grooves on the front of the chip, and then depositing boron-doped polysilicon to push the junction to form the anode region of the device. The grooved anode region is formed, which effectively solves the problem of limited current density of the conventional planar junction structure and improves the current density of the device

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