Theoretical analysis of mass and depth resolutions of cyclotron Rutherford backscattering spectrometry system

Cyclotron Rutherford backscattering spectrometry (CRBS), which utilizes the cyclotron motions of scattered ions in a uniform magnetic field, enables us to perform elemental depth profile measurements with an acceptance angle of larger than 10 msr and a relative energy resolution of better than 1%. CRBS thus allows precise measurements with less radiation damage in addition to the features of conventional RBS, i.e., nondestructive and quantitative measurements. In the present paper, the mass and depth resolutions of CRBS are theoretically examined. It is shown that CRBS can provide better mass resolution and a larger acceptance angle than conventional RBS or high-resolution RBS with a reasonably high depth resolution; hence, the CRBS system is a promising tool for thin film analysis.