Our new Zeiss Merlin FEG-SEM and High Resolution Bruker EBSD system have been installed. Arantxa Vilalte-Clemente and Hamidreza Abdolvand are getting to grips with the new instrument with help from Gabriella Chapman and Gareth Hughes in the EM research Support Group. A few days in and they already has some initial images of atomic terraces on GaN surfaces and threading dislocations making up mosiac cells in a thin InAlN film. These were obtained with the forescatter detectors on the Bruker EBSD system, with the sample highly tilted to the normal EBSD geometry.
This shows terraces and atomic steps on a (0001} GaN surface. Dislocations show as dot like features at the ends of the atomic steps.
Here the contrast indicates the small misorientations in the mosaic cell structure in a ~10nm thick (0001} InAlN layer. Dislocations can be seen along the edges of the cells.
Electron backscatter diffraction and electron channeling contrast imaging of tilt and dislocations in nitride thin films
C. Trager-Cowan and F. Sweeney, P. W. Trimby, A. P. Day, A. Gholinia, and N.-H. Schmidt, P. J. Parbrook, A. J. Wilkinson, and I. M. Watson
Physical Review B, (2007), vol. 75, 085301
Characterisation of nitride thin films by electron backscatter diffraction and electron channelling contrast imaging
C. Trager-Cowan, F. Sweeney, A. Winkelmann, A. J. Wilkinson, P. W. Trimby, A. P. Day, A. Gholinia, N. H. Schmidt, P. J. Parbrook and I. M. Watson
Materials Science and Technology (2006) vol.22, 1352-1358
Contact: Angus Wilkinson