https://doi.org/10.1051/epjap:2004047
Nanopipes in GaN: photo-etching and TEM study
1
National Center for HREM, Kavli Institute of Nanoscience
Delft University of Technology, Rotterdamseweg 137,
2628 AL Delft, The Netherlands
2
Experimental Solid State Physics III, RIM, University of
Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands
3
High Pressure Research Center, Polish Academy of Sciences,
Sokolowska 29/37, 01-142 Warsaw, Poland
Corresponding author: S.Lazar@tnw.tudelft.nl
Received:
19
June
2003
Accepted:
28
January
2004
Published online: 15 July 2004
Photochemical (PEC) etching and transmission electron microscopy (TEM) have been used to study the defects in hetero-epitaxial GaN layers. TEM proved that PEC etching reveals not only dislocations but also nanopipes in the form of protruding, whisker-like etch features. It is shown by diffraction contrast techniques that the nanopipes are screw coreless dislocations. An example is shown of the transformation of a normal full-core screw dislocation into a nanopipe. The PEC/TEM experiments indicate the presence of electrically active (recombinative) species in the vicinity of the nanopipes.
PACS: 61.72.Ff – Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.)
© EDP Sciences, 2004
