Evaluation of Defects in a SiC Substrate Using the Photoluminescence Measurement Method

Abstract

Photoluminescence (PL) imaging provide defect and dislocation characteristics not only in a 4H silicon carbide (SiC) epilayer but also in a substrate. In this work, to detect a large-pit or a bar-shaped stacking fault (BSF) before epilayer growth, we employed PL under various detection conditions. A large-pit was detected as a dark spot on a 4H-SiC substrate due to dislocations orthogonal to a micropipe. The BSF was clearly observed as a bright rectangle by tuning the observation conditions. The finding indicates that device killing defects or dislocations should be detected as soon as possible and thus improve the yield.