Work

Threshold voltage instability of SiC MOSFETs under very‐high temperature and wide gate bias

Year: 2024

Type: article

Abstract: Threshold voltage ( V TH ) instability affects the reliability of silicon carbide (SiC) MOSFETs. In this article, the influence of gate bias ( V GS ) and high temperature on V TH instability is investigated under wide V GS and very‐high temperature range (150°C to 275°C). The degradation mechanism of gate oxide under coupling of different electrical and thermal stress is revealed. When the device is subjected to + V GS, the relationship between V TH shift and temperature is not monotonic and there is a temperature turning point. This is mainly related to the capture/release and generation of electron traps. However, the V TH shift increases sharply and gate oxide breakdown for the device bias at +35 V, which is related to Fowler–Nordheim (F–N) tunnelling effect. For a large − V GS , the V TH shift is very small. Moreover, when the negative V GS decreases, the V TH shift is positively correlated with temperature, which may result from the activation and charge exchange of hole traps. However, the influence of moving ions changes the temperature dependence of V TH shift for the device bias at −30 V. Finally, the devices of different manufacturers are studied and similar change patterns are found. This finding provides guidance for the further application of SiC MOSFETs under high temperatures and different voltages.

Source: IET Power Electronics

DOI: 10.1049/pel2.12786

Authors: Cong Chen, Yumeng Cai, Peng Sun, Zhibin Zhao

Institution: North China Electric Power University

Language: English

Topic: Silicon Carbide Semiconductor Technologies

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,880

Funder: State Grid Corporation of China