Development of a cryo-FIB technique for the 3D structural characterization of liquid samples

The observation of three-dimensional distributions in some liquids or colloids is important, for example in cosmetics, functional paints and a catalyst. Furthermore, there is increasing demand to microscopically investigate the structures inside a liquid colloid, such as the interface of a dispersoid and dispersant. In order to meet these requirements, we have developed a cryo-transfer holder which is fully compatible between FIB and TEM/STEM. The cross section of frozen emulsions and a thin film sample were made by FIB-SEM (NB5000). As a result, the dispersion state of a dispersoid was observed by sequential FIB and SEM. Furthermore a 100nm thick sample was made by FIB and observed by 200 kV STEM (HD- 2700). The dispersoid (TiO₂ and Fe₂O₃) morphology and distribution were shown at nanometer level. (paper)