¹V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine, 41, prosp. Nauky, 03680 Kyiv, Ukraine
²Institute for Nanoscience & Engineering, University of Arkansas, W. Dickson 731, Fayetteville, Arkansas 72701, United States
³Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46 PL-02-668 Warsaw, Poland *E-mail: lubchenco.a@gmail.com

Abstract. Compositionally graded AlxGa1–xN alloys with the Al concentration in the (7 ≤ x ≤ 32) range were implanted with (Ar+) ions to study the structural and strain changes (strain engineering). It was shown that ion-implantation leads to ~0.3…0.46% hydrostatic strains and a relatively low damage of the crystal structure. The ion-implantation leads mainly to an increase of the density of point defects, while the dislocation configuration is almost unaffected. The density of microdefects is sufficiently reduced after the post-implantation annealing. The structural quality of the AlxGa1–xN layers strongly depends on the Al concentration and is worsen with increasing Al. The implantation induced structural changes in highly dislocated AlxGa1–xN layers are generally less pronounced. Based on the X-ray diffraction, a model is developed to explain the strain field behavior in the AlxGa1–xN/GaN heterostructures by migration of point defects and strain field redis-tribution. The approach to simulate 2θ/ω scans using statistical dynamical theory of X-ray diffraction for implanted compositionally graded structures AlGaN has been developed.

Keywords: AlxGa1–xN, graded layers, ion implantation, statistical X-ray diffraction theory, microdefects.

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