High resolution surface analysis by TOF-SIMS

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) has developed int o a mature technique meanwhile applied in many industrial laboratories for elemental and molecular surface characterization. Not only spectroscopic in formation but also information on the lateral distribution of surface speci es can be obtained (TOF-SIMS Imaging). The lateral resolution for the detec tion of elements is well beyond 100 nm using modern liquid metal ion Suns. For molecular species, however, the achievable lateral resolution not only depends on the performance of the instruments but also on sample parameters like obtainable secondary ion yield and the area disturbed on the sample b y impact of a single primary ion. Whereas for larger molecules the achievab le resolution can be several micron, imaging with sub-mu m resolution is po ssible if one monitors characteristic fragment ions.