Evaluation of Grain-Boundary Conduction of Dense AlN-SiC Solid Solution by Scanning Nonlinear Dielectric Microscopy

Dense and elemental homogeneous 2H AlN–SiC solid solution doped with Al and C was fabricated by using spark plasma sintering. The p‐type electrical conduction of the sample was confirmed by measurements of electrical conductivities and Seebeck coefficient. Dopant profiling of the sample by scanning nonlinear dielectric microscopy showed that the AlN–SiC grains respond to p‐type electrical conduction. These results indicated that added Al and C were dissolved to the grains and acted as p‐type dopants. In contrast, the grain boundaries did not show any response, suggesting the presence of depletion layer in the boundary.