Silicon carbide UMOSFET device integrated with TJBS

Abstract

The invention relates to a silicon carbide UMOSFET device integrated with a TJBS. The device comprises an N+ substrate region, an N- epitaxial region, a P-well region, an N+ injection region, first P+injection regions, second P+ injection regions, a grid electrode, a source electrode and a drain electrode, wherein the second P+ injection regions and the first P+ injection regions are arranged atintervals and are consistent in depth; first grooves are formed in the first P+ injection regions; second grooves are formed in the second P+ injection regions, the depth of the grid electrode is larger than that of the P-well region and smaller than these of the first P+ injection regions, the source electrode forms ohmic contact with the interfaces of the P-well region, the N+ injection region,the first P+ injection regions and the second P+ injection regions, and forms Schottky contact with the interface of the N-epitaxial region. According to the device, a groove structure is introducedinto a Schottky diode structure integrated in the device, so that the depths of the first P+ injection regions and the second P+ injection regions are increased, P+ injection is carried out on the surface of a thinner N-epitaxial region formed through etching, the depths of the P+ injection regions are larger, and the avalanche resistance of the device is improved.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, and in particular relates to a silicon carbide UMOSFET device integrating TJBS. Background technique [0002] In recent years, with the continuous development of power electronic systems, higher requirements have been placed on the power devices in the system. Silicon (Si)-based power electronic devices have been unable to meet the requirements of system applications due to the limitations of the material itself. As a representative of the third-generation semiconductor material, silicon carbide (SiC) materials are far better than silicon materials in many characteristics. Silicon carbide MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor, Metal-Oxide-Semiconductor Field-Effect Transistor) device, as a commercialized device in recent years, has an alternative in terms of on-resistance, switching time, switching loss and heat dissipation performance. The huge potential of the existi...

AI Technical Summary

Problems solved by technology

However, due to the large bandgap of silicon carbide materials, the turn-on voltage of the parasitic PiN diodes integrated in silicon carbide UMOSFET devices is mostly around 3V, which cannot provide freewheeling for the device itself, resulting in the internal freewheeling capability of silicon carbide UMOSFET devices. weaker

Therefore, in power electronic system applications such as full bridges, an additional Schottky diode is often used in antiparallel as a freewheeling diode, which greatly increases the complexity and cost of the circuit system.

In addition, in the blocking mode, a series of reliability problems will be caused due to the strong electric field of the gate oxide at the corner of the trench

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