In energetic-ion analysis and
Rutherford backscattering spectrometry, sample whose thickness is sufficiently small that the variation in energy of particles backscattered from atoms of each constitutive element is small with respect to the
system resolution.
Source:
PAC, 2020, 92, 1781. 'Glossary of methods and terms used in surface chemical analysis (IUPAC Recommendations 2020)' on page 1837 (https://doi.org/10.1515/pac-2019-0404)