4.5 kV-8 A SiC-Schottky Diodes / Si-IGBT Modules
Résumé
Due to the significant achievements in SiC bulk material growth and in SiC device processing technology, this semiconductor has received a great interest for power devices, particularly for SiC high-voltage Schottky barrier rectifiers. The main difference to ultra fast Si pin diodes lies in the absence of reverse recovery charge in SiC SBDs. This paper reports on 4.5kV-8A SiC Schottky diodes / Si-IGBT modules. The Schottky termination design and the fabrication process gives a manufacturing yield of 40% for large area devices on standard starting material. Modules have been successfully assembled, containing Si-IGBTs and 4.5kV-SiC Schottky diodes and characterized in both static and dynamic regimes. The forward dc characteristics of the modules show an on-resistance of 33mohm.cm2 @ room temperatue (RT) and a very low reverse leakage current density (JR < 10 5A/cm2 @ 3.5kV). An experimental breakdown voltage higher than 4.7kV has been measured in the air on polyimide passivated devices. This value corresponds to a junction termination efficiency of at least 80% according to the epitaxial properties. These SiC SBDs are well suited for high voltage, medium current, high frequency switching aerospace applications, matching perfectly as freewheeling diodes with Si IGBTs.