Two strain relaxation processes have been observed in AGaN layers grown on thick AlN templates. In Process I, a-type threading dislocations (TDs) with b = 1/3(112̄0) from the AlN underlayer are inclined away from the  axis toward the (11̄00) directions when they enter the AlGaN film, forming dislocation line projection perpendicular to the Burger vector. In Process II, a + c-type TDs from the AlN underlayer with Burgers vector of b = 1/3(112̄3) glide on (01̄11) planes when they enter the AlGaN film to generate interfacial misfit dislocations lying along the (2̄110) directions at the AlGaN/AlN interface.
ASJC Scopus subject areas
- Physics and Astronomy(all)