Three-Dimensional Analysis of Biological Samples using Dual FIB ToF-SIMS

Secondary Ion Mass Spectrometry (SIMS) has been used as an analysis tool for biological samples using cluster ions of C60, Bin, etc. However, because of bad focusing of cluster ions, accurate three-dimensional analysis is difficult. On the other hand, FIB (Focused Ion Beam) using Ga ions can be focused to about 50 nm, and applied to samples of micro region such as biological samples. However, three-dimensional analysis is difficult because of surface damage by primary ions. Therefore, we have developed Shave-off section processing method. Shave-off scan is extremely unique section processing method. Raster scan of FIB is very slow in vertical direction compared with in horizontal direction. In this study, we evaluated surface damage in section processing and carried out three-dimensional analysis of biological sample using Dual FIB ToF-SIMS with Shave-off scan. We evaluated surface damage by primary ions and actually analyzed biological sample with Shave-off scan. We demonstrated the utility of this instrument by analyzing biological samples.