FIB/SEM Characterization of Paper Materials

3D microscopy is of interest for structural characterization of paper materials to study the use of cellulose nanofibrils as a paper additive. Focused ion beam (FIB) tomography is a promising microscopy technique for this application, combining scanning electron microscopy (SEM) with serial sectioning by ion beam, potentially with nanoscale resolution. In this work, FIB tomography is demonstrated for paper samples, showing that the technique is applicable to this class of materials. Volume reconstructions with voxel resolution down to 13x13x 15nm3 for volumes of up to approximately 10x10x2 μm3 are obtained. The latter is limited by the acquisition time, and can therefore be extended. A working protocol is developed, from sample preparation and image acquisition to processing and volume reconstruction. The method is discussed in comparison to established 3D methods for paper materials, and suggestions are made for improving the resolution and increasing the volume