Superjunction metal-oxide-semiconductor field effect transistor (MOSFET) containing p-SiC and integrated with Schottky diode

Abstract

The invention provides a superjunction metal-oxide-semiconductor field effect transistor (MOSFET) device. A second type of semiconductor area of the second conductive type in a voltage withstanding layer of the MOSFET device can be made of silicon carbide materials, a first type of semiconductor area of the first conductive type in the voltage withstanding layer of the MOSFET device can be made ofsilicon materials, at least part of the upper surface of the first type of semiconductor area of the first conductive type in the voltage withstanding layer makes contact with a conductor to form a Schottky contact electrode, and the Schottky contact electrode is connected with a source electrode through a wire. Compared with a common superjunction MOSFET device, the breakdown voltage of the superjunction MOSFET device is more not prone to being affected by charge non-equilibrium, and the reverse recovery characteristics of a diode are better.

Description

technical field [0001] The invention belongs to semiconductor devices, especially semiconductor power devices. Background technique [0002] Superjunction Metal-Oxide-Semiconductor Field Effect Transistor (Superjunction Metal-Oxide-Semiconductor Field Effect Transistor, Superjunction MOSFET) is a widely used power switching device with superior performance. The super-junction MOSFET adopts a voltage-resistant structure in which n-column regions / p-column regions are arranged alternately, which can enable the n-column region and p-column region to obtain a higher breakdown voltage at a higher doping concentration. Therefore, the on-resistance of super-junction MOSFETs is usually relatively low. However, super-junction MOSFETs also have two major disadvantages. [0003] First, the super-junction MOSFET needs to precisely control the doping concentration of the n-column region and the p-column region to achieve charge balance (that is, the total number of effective donor impur...

AI Technical Summary

Problems solved by technology

Excess ionized donors in the N-pillar region will significantly increase the highest electric field at the top of the n-pillar region, while excess ionized acceptors in the p-pillar region will significantly increase the highest electric field at the bottom of the p-pillar region, which will lead to the breakdown voltage of the superjunction MOSFET significantly reduce

[0004] Second, the reverse recovery characteristics of the body diode of the super junction MOSFET are relatively poor

However, this approach increases the reverse recovery charge and also increases the on-resistance

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