Auriga small dual beam fib sem

Imaging of internal crystal morphology was performed using a Zeiss Auriga Small Dual-Beam FIB-SEM.^{12 (link),13} For these analyses all samples were first coated with 4 nm iridium prior to SEM imaging, then coated with 50 nm of Au prior to performing FIB. A 30 kV 120 pA gallium ion beam was oriented perpendicular to the sample by tilting the sample stage to 54° and utilized to mill 15 nm serial cross-sections. SEM images of cross-sectioned surfaces were then obtained using a 2.0 kV 600 pA electron beam and a secondary electron detector at a working distance of 5.0 mm. Images of surfaces containing electron beam damage were created for comparison to images of undamaged surfaces but were not used for the purposes of discussion in this publication. Images were taken shortly after cross sectioning to limit the exposure of the uncoated surfaces to the electron beam.^{12 (link),13}