Structure and chemistry of the (111)Sc2O3/(0001) GaN epitaxial interface

The structure and chemistry of the (111)Sc2O3/(0001) GaN epitaxial interface grown by molecular-beam epitaxy have been investigated. High-resolution transmission electron microscopy reveals an abrupt Sc2O3/GaN interface with a hexagonal misfit dislocation network. These dislocations have Burgers vectors of (a/3)< 11 (2) over bar0 >(GaN) and line directions parallel to < 1 (1) over bar 00 >(GaN), with an average spacing of similar to 3.8 nm. Scanning transmission electron microscopy and electron energy loss spectrometry reveal the intermixing of Sc, O, and N over a region with a width of similar to 1.5 nm at the interface. (C) 2010 American Institute of Physics. [doi:10.1063/1.3454924]