Characterization of Dislocations in GaN Thin Film and GaN/AlN Multilayer

The dislocations in GaN thin film with GaN/AlN multilayer (ML) as the buffer layer were evaluated using transmission electron microscopy. A high density of dislocations parallel to the GaN/ML interface and a sudden decrease in the dislocation density at the GaN/ML interface were found. Dislocation propagation in the direction parallel to the GaN/ML interface by turning horizontally on the GaN/ML interface is considered to be effective in decreasing the dislocation density at the top layer of GaN.