Crystal quality evaluation of 6H-SiC layers grown by liquid phase epitaxy around micropipes using micro-Raman scattering spectroscopy

We performed homoepitaxial growth of 6H-SiC layers on substrates including micropipes by the LPE method and evaluated the crystal quality by Raman scattering spectroscopy. In particular, we focused on the crystal quality of layers covering micropipes. It was made clear that there is no stress due to morphological macroscopic defects in the crystal over micropipes. Moreover, LPE growth not only closes a micropipe but also reduces the inhomogeneity of carrier density which exists in the area of the micropipe before growth.