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Strain Relaxation in an AlGaN/GaN Quantum Well System

  • P D Cherns
  • C McAleese
  • M J Kappers
  • C J Humphreys
Part of the Springer Proceedings in Physics book series (SPPHY, volume 120)

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.

Keywords

Slip System Burger Vector Half Plane Misfit Dislocation Strain Relaxation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Reference

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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  • P D Cherns
    • 1
  • C McAleese
    • 1
  • M J Kappers
    • 1
  • C J Humphreys
    • 1
  1. 1.Department of Materials Science and MetallurgyUniversity of CambridgeCambridgeUK

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