Open AccessАнализ особенностей кристаллической структуры НЕМТ-гетероструктур GaN/Al-=SUB=-0.32-=/SUB=-Ga-=SUB=-0.68-=/SUB=-N по данным рентгеновской дифрактометрии методом Вильямсона-Холла
Author(s) -
С. С. Пушкарев,
М. М. Грехов,
Н.В. Зенченко
Publication year - 2018
Publication title -
fizika i tehnika poluprovodnikov
Language(s) - English
Resource type - Journals
eISSN - 1726-7315
pISSN - 0015-3222
DOI - 10.21883/ftp.2018.06.45920.8661
Subject(s) - intensity (physics) , diffraction , polynomial , scattering , inverse , domain (mathematical analysis) , function (biology) , degree (music) , physics , materials science , probability density function , computational physics , optics , mathematics , condensed matter physics , geometry , mathematical analysis , statistics , evolutionary biology , acoustics , biology
The fitting of θ/2θ and ω peaks in X-ray diffraction curves is shown to be most accurate in the case of using an inverse fourth-degree polynomial or probability density function with Student’s distribution (Pearson type VII function). These functions describe well both the highest-intensity central part of the experimental peak and its low-intensity broadened base caused by X-ray diffuse scattering. The mean microdeformation ε and mean vertical domain size D are determined by the Williamson–Hall method for layers of GaN (ε ≈ 0.00006, D ≈ 200 nm) and Al_0.32Ga_0.68N (ε = 0.0032 ± 0.0005, D = 24 ± 7 nm). The D value obtained for the Al_0.32Ga_0.68N layer is most likely to result from the nominal thickness of this layer, which is 11 nm.