Secondary ion mass spectrometry (SIMS) and Rutherford backscattering spectrometry (RBS) were used for the characterization of SrS thin films doped with SiCl4 and Ce, and to establish the correlation of SIMS intensities with chlorine concentration. The film thicknesses were determined by RBS and X-ray fluorescence spectrometry. Two types of doped SrS samples were studied: SiCl4-codoped SrS : Ce thin films and SiCl4-doped SrS thin films. The SrS thin films were deposited on alumina-coated soda-lime glass substrates by the atomic layer epitaxy process. The quantification of SIMS intensities was performed by plotting the intensity ratio of the chlorine and sulfur against the chlorine concentration measured by RBS. Correlation factors for the calibration graphs were 0.997 for SrS : Ce, SiCl4 and 0.993 for SrS : SiCl4 in the chlorine concentration range 0–5.3 at.-%.