Korrelation von Materialqualität und Ausfallmechanismen leistungselektronischer SiC-Bauelemente

Description

The purpose of this work was to establish a correlation between the material defects in Silicon Carbide (SiC) and failure modes of high-voltage and high-power 4H-SiC semiconductor trench-MOSFET devices. N-type SiC homoepitaxial layers were grown to be able to investigate epilayers in addition to the substrates. These layers were analysed for their surface and crystallographic defects. The method of characterisation was utilizing confocal as well as differential interference contrast (DIC) optics for surface inspection and ultra-violet photoluminescence (UV-PL) imaging. The defect-characterized epitaxial wafers were then used to manufacture trench-MOSFET devices. All finished devices were electrically tested. The electrical yield received through this method was then overlayed with the defect data previously measured during processing. Finally, those extensively investigated devices were used for reliability tests.