Depth profiles and resolution limits in accelerator-based solid state analysis

摘要

A ubiquitous problem in solid state analysis is the determination of the elemental composition of a sample as a function of the depth. The deterination of the depth profiles from ion-beam experiments is an ill-posed inversion problem due to ion-beam and detector-induced energy spreads as well as energy-loss straggling and small-angle scattering effects. The inversion problem is solved in the framework of Bayesian probability theory, which provides a method for quantifying and combining uncertain data and uncertain additional information. By deconvolving the apparatus transfer function and modeling the scattering events in the sample we reconstructed depth profiles of ~(13)C in tetrahedral amorphous carbon (ta-C) and depth profiles in ~(12)C/~(13)C marker probes. An enhancement of the energy resolution by a factor of 6 was obtained.