Coincidence Counting in Time-of-Flight Mass Spectrometry: A Test for Chemical Microhomogeneity

See allHide authors and affiliations

Science  25 May 1990:
Vol. 248, Issue 4958, pp. 988-990
DOI: 10.1126/science.248.4958.988


Coincidence counting techniques have been combined with time-of-flight mass spectrometry in the examination of surfaces for chemical microhomogeneity. A mathematical formalism was developed to describe the principles underlying this coincidence counting technique and was used to produce a quantitative method for handling the data obtained. This technique of testing for chemical homogeneity has been demonstrated with a sample that consists of a physical mixture of polystyrene and crystals of NaF which were tenths of micrometers in diameter. Ultimately this approach is expected to be useful for the routine testing of surfaces for chemical homogeneity at the level of tens of nanometers.

Stay Connected to Science