Nondestructive analysis of propagation of stacking faults in SiC bulk substrate and epitaxial layer by photoluminescence mapping

The effectiveness of room -temperature photoluminescence (PL) mapping was demonstrated for nondestructive detection of in-grown stacking faults in off-axis 4H-SiC bulk substrates and epitaxial layers. The use of a deep-UV light excitation is essential to detect the stacking fault related intensity pattern in the bulk substrates because of its shallow penetration depth. A bar-shaped PL intensity pattern agreed well with the etch-pit pattern due to the stacking faults in the bulk substrate. The expansion length of the bar pattern from a bulk substrate to an epitaxial layer corresponded to the projected width of basal plane in the epitaxial layer. These results allowed us to analyze the stacking faults propagated from the bulk substrate to the epitaxial layer.