This dataset provides the as acquired electron channelling contrast (ECCI) images used to generate figures 4 a) and b) in the paper "AlN overgrowth of nano-pillar-patterned sapphire with different offcut angle by metalorganic vapor phase epitaxy".
Electron channelling contrast imaging is a non-destructive, diffraction technique performed in the scanning electron microscope. ECCI images are generally constructed by measuring the intensity of the backscattered electrons (BSEs) as the electron beam scans across the surface of a suitably-orientated sample. Any changes in crystallographic orientation and local strain can be monitored by the variation in the BSE intensity causing a change in contrast in an ECCI image. This allows the imaging of low-angle tilt and rotation boundaries, atomic steps and extended defects (e.g. TDs).
The ECCI image of Fig 4 a) was acquired at an electron beam energy of 30 keV and the ECCI image of Fig 4 b) was acquired at an electron beam energy of 25 keV using an FEI Quanta 250 Schottky field emission gun environmental/variable pressure SEM operated in low vacuum mode (0.5 mbar) to avoid charging of the insulating specimens.