A Power MOSFET with P-base Schottky Diode and Built-in Channel Diode for Fast Reverse Recovery

Ping Li,Jingwei Guo,Zhi Lin,Shengdong Hu

doi:10.1109/jeds.2021.3060152

Ping Li, Jingwei Guo + Show 2 more

Open Access

https://doi.org/10.1109/jeds.2021.3060152

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Abstract

A power MOSFET with P-base Schottky diode and built-in channel diode is proposed and numerically investigated in this article. The P-base Schottky diode formed by the P-base Schottky contact is in reverse series with the P-base/N-drift junction diode. Besides, by coupling the gate of the dummy MOSFET to the source, a built-in channel diode is introduced, which provides a unipolar reverse conduction current path and drastically reduces the gate-to-drain charge. When the proposed MOSFET serves as the freewheeling diode, the reverse-biased P-base Schottky diode inactivates the P-base/N-drift junction diode, so that the reverse current will be carried out by the built-in channel diode. As a result, in comparison with the planar gate power MOSFET, the reverse recovery charge and the gate-to-drain charge could be reduced by 96.9 % and 75.4%, respectively.

Highlights

The power metal-oxide-semiconductor field-effect transistors (MOSFETs) are widely adopted in high-frequency power switching applications due to their fast switching capability when compared with the bipolar devices
Due to a large number of the minority carriers in the drift region during the reverse conduction period, the body PiN diode of the power MOSFETs suffers from a high reverse recovery current and a high reverse recovery charge
We propose a new power MOSFET architecture by integrating a built-in channel diode and a P-base Schottky diode

Summary

INTRODUCTION

The power metal-oxide-semiconductor field-effect transistors (MOSFETs) are widely adopted in high-frequency power switching applications due to their fast switching capability when compared with the bipolar devices. Due to a large number of the minority carriers in the drift region during the reverse conduction period, the body PiN diode of the power MOSFETs suffers from a high reverse recovery current and a high reverse recovery charge. Minority carriers lifetime control and integrated Schottky diode have been developed, but they tend to degrade the leakage current or the on-state voltage of the power MOSFETs [10]–[16]. Reverse-biased P-type Schottky diode, so the injection of the minority carriers is suppressed and the reverse current would be conducted by the unipolar built-in channel diode during the reverse conduction state. When q Bp is low, a huge leakage current would flow through the body PiN diode, leading to a large number of the minority carriers in the N-drift region. The P-base Schottky diode could be very effective in suppressing the injection of the minority carriers when q Bp is equal to or higher than 0.5 eV

The reverse recovery characteristics of the proposed

Findings

CONCLUSION