Structural properties of quaternary InAlGaN MQWs grown by plasma-assisted MBE
|George P. Dimitrakopulos 2, Philomela Komninou 2, Thomas Kehagias 2, Joseph Kioseoglou 2, Alexandros Georgakilas 3, Gerard Nouet 1, Theodoros Karakostas 2|
1. SIFCOM, UMR6176, CNRS-ENSICAEN, 6 Bld Maréchal Juin, Caen 14050, France
Quaternary InxAlyGa1-x-yN multiple quantum wells (MQWs) with nominal composition x = 0.085, y = 0.285, and GaN spacers are characterized by high resolution transmission electron microscopy (HRTEM), geometric phase analysis (GPA), and energy dispersive x-ray nano-analysis in a scanning transmission electron microscope (STEM). The MQWs were grown by rf plasma MBE using metal-rich conditions and a relatively low growth temperature. Specimen preparation was performed by tripod polishing in order to minimize artifacts due to excessive ion milling. The material exhibits sharp well-defined interfaces. Indium clustering is not observed; the onset of clustering occurs only after prolonged observation under the electron beam. The GPA indicates that the quantum wells are lattice-matched to the GaN spacers. The chemical concentration profiles are obtained by de-convolution of EDX scans and confirm the chemical sharpness of the interfaces.
Presentation: poster at E-MRS Fall Meeting 2005, Symposium F, by George P. Dimitrakopulos
See On-line Journal of E-MRS Fall Meeting 2005
Submitted: 2005-05-30 13:09 Revised: 2009-06-07 00:44