Time-of-Flight Secondary Mass Spectrometry (TOF-SIMS) is widely used inindustrial fields such as impurity analysis of semiconductors,analysis of hightechnology micro scale materials,and mass spectroscopy of polymer and organicmaterials,because it provides high sensitivity detection of all elements and manymolecular species,simultaneously.In these analyses,there are quite a lot oftopographic rough samples such as fibers,nozzles,trenches,and so on.However,there were some limitations to apply it to these samples due to the high bias voltagewith small gap between the sample and extraction plate of secondary ions.In thisstudy,in order to analyze these samples without significant loss of the secondary ionsignal,we have investigated the field effect around the topographic rough conductivesamples using SIMION code and have established an optimized characterizationmethod for these samples.In the presentation,we will discuss the result of theinvestigation and show you the practical applications.