Cracks in GaN/AlN multiple quantum well structures grown by MBE
2008 (English)In: Journal of Physics, Conference Series, ISSN 1742-6588, E-ISSN 1742-6596, Vol. 100, 042026- p.Article in journal (Refereed) Published
Due to the large lattice constant mismatch and thermal expansion coefficient difference between GaN and AlN, large strain is generated inside the GaN/AlN multiple quantum wells, which causes cracks in the structure. We investigated such cracks by optical microscopy and AFM. The crack density was studied with buffer and cap layer thickness, the number of quantum well periods, and the temperature reduction rate after growth as parameters. It was found that the crack density increased exponentially, with the number of periods above 4. Besides, a very thin, 100 nm, GaN buffer layer and similar to 300 nm GaN cap layer greatly reduced the crack density.
Place, publisher, year, edition, pages
Institute of Physics (IOP), 2008. Vol. 100, 042026- p.
IdentifiersURN: urn:nbn:se:kth:diva-87846DOI: 10.1088/1742-6596/100/4/042026ISI: 000275655200074ScopusID: 2-s2.0-58749099363OAI: oai:DiVA.org:kth-87846DiVA: diva2:501971
17th Int. Vacuum Congress and 13th Int. Conf. on Surface Science
QC 201202212012-02-142012-02-142012-02-21Bibliographically approved