Different defective structures of nitrogen-doped 6H-SiC single crystals were examined using a combination of laser scanning confocal microscopy (LSCM), scanning electron microscope (SEM) and KOH-K(2)CO(3) etching. The form, depth and size of the defects in etched silicon carbide (SiC) crystals were observed by LSCM. Using these 3D LSCM images, defective structures varying in the growth direction were observed from a side view for the first time. To study the size, depth and form of defect etch pits in detail, we observed the defect etch pits configuration in some volumes through taking 3D LSCM pictures. Information on defects obtained using this approach will be very helpful for investigation of MP and SD formation mechanism in conducting SiC substrates, as well as the observation of polytype stability in nitrogen-doped SiC crystals.