Defect structure of high temperature hydride vapor phase epitaxy-grown epitaxial (0Â 0Â 0Â 1) AlN/sapphire using growth mode modification process

Above 2 μm thickness, the film consists of isolated threading dislocations with a total density of 8 × 108 cm−2. Most of threading dislocations are either pure edge or mixed dislocations. The threading dislocation reduction in these films is associated with dislocation loops formation and dislocation aggregation-interaction during island growth with high V/III ratio.