Performance and Reliability Review of 650 V and 900 V Silicon and SiC Devices: MOSFETs, Cascode JFETs and IGBTs

Jose Ortiz Gonzalez,Olayiwola Alatise,Saeed Jahdi,Ruizhu Wu

doi:10.1109/tie.2019.2945299

Abstract

The future of power conversion at low-to-medium voltages (around 650 V) poses a very interesting debate. At low voltages (below 100 V), the silicon (Si) MOSFET reigns supreme and at the higher end of the automotive medium-voltage application spectrum (approximately 1 kV and above) the SiC power MOSFET looks set to topple the dominance of the Si insulated-gate bipolar transistor (IGBT). At very high voltages (4.5 kV, 6.5 kV and above) used for grid applications, the press-pack thyristor remains undisputed for current source converters and the press-pack IGBTs for voltage source converters. However, around 650 V, there does not seem to be a clear choice with all the major device manufacturers releasing different technology variants ranging from SiC Trench MOSFETs, SiC Planar MOSFETs, cascode-driven WBG FETs, silicon NPT and Field-stop IGBTs, silicon super-junction MOSFETs, standard silicon MOSFETs, and enhancement mode GaN high electron mobility transistors (HEMTs). Each technology comes with its unique selling point with gallium nitride (GaN) being well known for ultrahigh speed and compact integration, SiC is well known for high temperature, electro-thermal ruggedness, and fast switching while silicon remains clearly dominant in cost and proven reliability. This article comparatively assesses the performance of some of these technologies, investigates their body diodes, discusses device reliability, and avalanche ruggedness.

Highlights

S ILICON technology has dominated power electronics for decades with silicon MOSFETs applied in Manuscript received May 1, 2019; revised August 9, 2019; accepted September 17, 2019
The results show that silicon carbide (SiC) MOSFETs still lag the silicon devices as far as gate oxide reliability is concerned
This article presented a comparative analysis of automotive medium voltage 650 V power devices including SiC Planar MOSFETs, SiC Trench MOSFETs, CoolMOS, SiC Cascode, and field stop insulated-gate bipolar transistor (IGBT)

Summary

INTRODUCTION

S ILICON technology has dominated power electronics for decades with silicon MOSFETs applied in Manuscript received May 1, 2019; revised August 9, 2019; accepted September 17, 2019. A good way to compare power devices from different technologies is to use figures-of-merit (FOM) that account for die area including specific-ON-state resistance (RSPEC ) and RON ∗ QG (which accounts for the tradeoff between conduction and switching losses.) Table II shows the results of this comparison using values taken from datasheets Because these parameters are often measured under different conditions, it is necessary to compare these devices under the same test conditions.

CONDUCTION PERFORMANCE

SWITCHING PERFORMANCE

BODY DIODES

AVALANCHE RUGGEDNESS

GATE OXIDE RELIABILITY

CONCLUSION