tailieunhanh - Báo cáo hóa học: " Strain Relief Analysis of InN Quantum Dots Grown on GaN ´ ´ Juan G. Lozano Æ Ana M. Sanchez Æ Rafael Garcıa Æ ´ Sandra Ruffenach Æ Olivier Briot Æ David Gonzalez"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Strain Relief Analysis of InN Quantum Dots Grown on GaN ´ ´ Juan G. Lozano Æ Ana M. Sanchez Æ Rafael Garcıa Æ ´ Sandra Ruffenach Æ Olivier Briot Æ David Gonzalez | Nanoscale Res Lett 2007 2 442-446 DOI s11671-007-9080-6 NANO EXPRESS Strain Relief Analysis of InN Quantum Dots Grown on GaN Juan G. Lozano Ana M. Sanchez Rafael García Sandra Ruffenach Olivier Briot David Gonzalez Received 19 May 2007 Accepted 18 July 2007 Published online 10 August 2007 to the authors 2007 Abstract We present a study by transmission electron microscopy TEM of the strain state of individual InN quantum dots QDs grown on GaN substrates. Moire fringe and high resolution TEM analyses showed that the QDs are almost fully relaxed due to the generation of a 60 misfit dislocation network at the InN GaN interface. By applying the Geometric Phase Algorithm to plan-view high-resolution micrographs we show that this network consists of three essentially non-interacting sets of misfit dislocations lying along the ZĨ2Ĩ0 directions. Close to the edge of the QD the dislocations curve to meet the surface and form a network of threading dislocations surrounding the system. Keywords Misfit relaxation Strain mapping High misfit interface HRTEM InN Introduction Indium Nitride InN with a band gap of eV 1 2 has become the focus of increased attention among the III-N compounds due to its potential for near-infrared optoelectronic devices or high efficiency solar cells 3 . Moreover the combination of the intrinsic properties of InN with quantum phenomena 4 resulting from the J. G. Lozano El A. M. Sanchez R. García D. Gonzalez Departamento de Ciencia de los Materiales e Ingeniería Metalurgica y Quimica Inorganica Facultad de Ciencias Universidad de Cadiz 11510 Puerto Real Cadiz Spain e-mail S. Ruffenach O. Briot Groupe d Etilde des Semiconducteurs UMR 5650 CNRS Place Eugene Bataillon Universite Montpellier II 34095 Montpellier France growth of self-assembled quantum dots QDs promises further applications. However the fabrication of high quality crystalline InN is not straightforward one of the main difficulties is the lack of a .