InN polarity determination by convergent-beam electron diffraction

摘要

To establish an accurate determination technique for the polarity of InN by convergent-beam electron diffraction (CBED), we clarified the influence of the electron incidence direction, film thickness, and the temperature factor B on CBED patterns by simulation. The electron incidence direction of [1100] and a film thinner than 50 nm were found to be preferable for easy and reliable polarity determination. Using an InN film grown on a (0001) GaN template on (0001) sapphire by metalorganic vapor-phase epitaxy, observation of the CBED pattern in the thin region of the film was confirmed from the simulation result. This InN film was clearly determined to have N polarity and the value of B was estimated to be less than 2.0 A~2.