ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Strain relaxation in the GaN/AlN/6H-SiC epitaxial system grown by vicinal surfaceepitaxy (VSE) is investigated and compared with that in on-axis epitaxy. High resolution x-raydiffraction (HRXRD) measurements show that GaN films grown by VSE have improved crystallinequality. High resolution transmission electron microscope (HRTEM) studies reveal that there aretwo types of misfit dislocations (MDs) at AlN/6H-SiC interfaces: 60˚ complete dislocations along〈1120 〉 directions with Burgers vector 1/3〈1120 〉 and 60˚ Shockley partials along 〈10 10 〉directions with Burgers vector 1/3〈10 10 〉. The latter are usually geometrical partial misfitdislocations (GPMDs) that are dominant in VSE to accommodate the lattice mismatch and stackingsequence mismatch simultaneously. In VSE, it is the high-density GPMDs formed at the vicinalsurface steps that facilitate rapid strain relaxation at the initial stage of deposition and hence lead tosuperior crystalline quality of the subsequently grown GaN films
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/14/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.527-529.1513.pdf
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