Structural analysis of (Ga,Mn)N epilayers and self-organized dots using MeV ion channeling

Rutherford backscattering (RBS) and particle-induced X-ray emission (PIXE) experiments were performed on (Ga,Mn)N epilayers and self-organized dots grown by plasma-assisted MBE. The combined channeling RBS and Mn PIXE experiments were performed on Ga0.949Mn0.051N epilayer, which was confirmed to be of pure diluted phase by X-ray difffaction (XRD) in our previous study, in order to check the presence of Mn atoms in the interstitial site in wurtzite crystal. The axis scan around < 0001 > and < 10 (1) over bar2 > axes and the plane scan around (10 (1) over bar0) plane revealed that almost all the Mn atoms were in the substitutional site of wurtzite GaN crystal. For self-organized dots of (Ga,Mn)N grown on AlN by MBE, the PIXE spectra were measured and the Mn composition in the dot layer was estimated from the ratio of emission intensity of Mn and Ga K-alpha lines. At a result, it was found that the Mn composition in the dots was higher by two or three times than that in thick epilayers grown with the addition of the same amount of Mn flux. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.