Local Structure Analysis of Ga1-xAIxN Epitaxial Layer

We used the strained-tetrahedron model to interpret published extended x-ray absorption fine structure data on the wurtzite structure of epitaxial GaAIN thin films grown on a sapphire substrate. Site occupation preference coefficients were determined and the nearest neighbour and next-nearest neighbour interion distances were estimated. The three observed ion-pair preference coefficients and the related configuration population coefficients strongly deviate from the random distribution, which indicates that the occurrence of tetrahedral with 1AI+3Ga is highly improbable. Moreover, instead of the eight lines expected the GaAIN phonon spectra display only four strong lines. Finally, the analysis suggests that beyond a concentration of 50% of AI, these thin films grow less homogeneously whatever the method of preparation.

ROBOUCH B.V.;  KISIEL Andrej;  ROBOUCH Piotr;  KUTCHERENKO I.;  VODOPYANOV L. K.;  INGROSSO L.;  MARCELLI A.; 

2008-11-12

AMER INST PHYSICS

JRC48564

0021-8979,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC48564,