Modelling of indium rich clusters in MOCVD InxGA1-xN/GaN multilayers

[摘要] Chemical composition in a ternary alloy is examined using a quantitative high resolution transmission electron microscopy, finite element modelling of the thin foil relaxation phenomena and microscopy image simulation. The measurement of local lattice distortion on transmission electron microscopy images is a powerful tool for chemical composition determination. However, for the correct interpretation of the results, one needs to take into account the inhomogeneous relaxation of the sample and the strain averaging across the sample. The 3D finite element modelling of such phenomena have been performed as a function of chemical composition and geometry of an indium rich cluster in a MOCVD InxGal-N-x/GaN quantum well. Lattice distortion field measured on: experimental transmission electron microscopy image and simulated one, obtained on the basis of finite element simulation, are compared. This procedure allows an accurate determination of chemical composition in such heterostructures. (C) 2004 Elsevier B.V. All rights reserved.

[发布日期] 2004-11-17

[效力级别]  Proceedings Paper

[关键词] indium clusters;vapour deposition;transmissionelectron microscopy;elasticity;finite element method;lattice distortion;image simulation