Summary
AlGaN/GaN quantum well stacks have been grown in a series with 10.5nm Al0.5Ga0.5N barriers and 1.5nm, 2.5nm and 3.5nm GaN wells. These samples have been studied by weak beam dark field (WBDF) TEM. Threading dislocations form ‘staircases’ in the stack, generating a short misfit segment at the lower interface of each well. By imaging dislocations at different tilts and opposite values of the deviation parameter s, it is established that the misfit segments are pure edge type and relieve strain in the GaN layers. Two mechanisms are proposed for the formation of these ‘staircase’ structures by climb.
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsPreview
Unable to display preview. Download preview PDF.
Reference
Cherns P D, McAleese C, Kappers M J and Humphreys C J 2005 Springer Proc. in Phys. 107, 55
Matthews J W 1979 Misfit Dislocations, in Dislocations in Solids Vol 2 ed Nabarro F R N pp. 461–545
Srinivasan S, Geng L, Liu R, Ponce F A, Narukawa Y and Tanaka S 2003 Appl. Phys. Lett. 83, 5187
Costa P M F J, Datta R, Kappers M J, Vickers M E, Humphreys C J, Graham D M, Dawson P, Godfrey M J, Thrush E J and Mullins J T 2006 Phys. Stat. Sol. a 203, 1729
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2008 Springer Science+Business Media B.V.
About this paper
Cite this paper
Cherns, P.D., McAleese, C., Kappers, M.J., Humphreys, C.J. (2008). Strain Relaxation in an AlGaN/GaN Quantum Well System. In: Cullis, A.G., Midgley, P.A. (eds) Microscopy of Semiconducting Materials 2007. Springer Proceedings in Physics, vol 120. Springer, Dordrecht. https://doi.org/10.1007/978-1-4020-8615-1_5
Download citation
DOI: https://doi.org/10.1007/978-1-4020-8615-1_5
Publisher Name: Springer, Dordrecht
Print ISBN: 978-1-4020-8614-4
Online ISBN: 978-1-4020-8615-1
eBook Packages: Chemistry and Materials ScienceChemistry and Material Science (R0)