Development of non-destructive in-house observation techniques for dislocations and stacking faults in SiC epilayers

We have developed non-destructive in-house observation techniques for dislocations and stacking faults (SFs) in 4H-SiC epilayers. Low temperature photoluminescence (PL) mapping was carried out at 100K using He-Cd laser (325 nm) as an exciation source. PL mapping at similar to 420 mm was used to investigate basal plane dislocations (BPDs), Shockley stacking faults (SSFs) and boundary, while PL mapping at similar to 470 nm and 100K obtained in-grown SF images. In addition, using a high-resolution laboratory X-ray topography system with a four-crystal collimator, we succeeded in recording BPDs propagating along [11-20]. From the measurement results, new evaluation techniques for dislocations and SFs other than KOH etching and Synchotron radiation topography were demonstrated on Si- and C-face 4H-SiC epilayers.