Preferential N‐H bond direction in GaAsN grown by chemical beam epitaxy

The two N-H local vibrations in GaAsN grown by the chemical beam epitaxy have the same preferential orientation in the crystal. The bond orientations of the N-H wagging mode at 961 cm-1 and stretching mode at 2952 cm-1 tend to align along [1-10]. The peak intensities of the three major N-H local vibration modes were examined by the polarized Fourier transform infrared spectroscopy. The integrated absorption peaks at 961and 2952 cm-1 showed the two-fold rotational symmetry in (001) plane, while the one at 3098 cm-1 was almost constant within the accuracy of this measurement. The maximum peak intensities were observed when the IR polarization direction was [110] for the N-H wagging mode at 961 cm-1, and [1-10] for the N-H stretching mode at 2952 cm-1, which means that those bond orientations projected on (001) plane were the same. The result indicates that the N-H wagging mode at 961 cm-1 and stretching mode at 2952 cm-1 are originated from the same N-H bond. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)