We are evaluating the use of polyatomic and cluster primary ion beams for characterization of semiconductor materials by secondary ion mass spectrometry using both magnetic sector and time-of-flight SIMS instruments. Primary ion beams ofSF5+,C8−andCsC6−have been used to analyze low energy arsenic implants in silicon, boron delta-doped structures, thin gate oxides, metal multilayers, organic surface contamination and photoresist thin films. Compared to monoatomic bombardment under the same conditions, cluster ion beams offer improved depth resolution for silicon depth profiling and a reduction in sputter-induced topography for metals. For organic materials, the use of a cluster ion beam can give large improvements in yield for characteristic secondary ions and can minimize beam-induced degradation in some materials. ©2001 American Institute of Physics.