Tritium analysis in zirconium film with BIXS and EBS: Generality test of Al thin film as the β-ray stopping layer in BIXS

The tritium analysis in tritium/deuterium-containing zirconium thin films was performed using elastic backscattering spectrometry (EBS) and β-ray induced X-ray spectrometry (BIXS). The EBS energy spectra were simulated with the SIMNRA program to obtain the tritium depth profiles and the total tritium contents in the samples. Two stopping powers used in the SIMNRA program were compared and it was shown that the SRIM stopping power in the simulations was better than the Ziegler/Biersack stopping power. In the BIXS that incorporated Monte Carlo simulation data, the β-ray stopping layers between the X-ray detector and the sample were Al thin film (BIXS-Al) and Ar gas (BIXS-Ar), respectively. The pile-up effects for BIXS X-ray spectra were corrected using Monte Carlo method for the first time. The tritium depth profiles and the total tritium contents in zirconium thin films obtained by the BIXS-Ar, BIXS-Al, EBS and the pressure, volume and temperature (PVT) method were compared. The possible reasons for the difference between the BIXS-Ar and BIXS-Al were discussed and the generality of Al thin film as the β-ray stopping layer was tested and a standard procedure of BIXS method for analyzing tritium-containing solid materials was proposed, in which the BIXS-Al method was recommended.