Improvement in automated particle measurement using micromanipulation and large geometry secondary ion mass spectrometry to remove the particle mixing effect of uranium particles

A new automated particle measurement (APM) combined with micromanipulation using a large geometry secondary ion mass spectrometry instrument was proposed and demonstrated to remove the particle mixing effect. The particle mixing effect means that the aggregation of uranium particles is detected as a single uranium particle. The particle mixing effect provides instrument operators with nonexistent isotopic abundances of the uranium particle in a sample. In this study, the micromanipulation technique was used to remove the particle mixing effect from the APM results. A test sample containing different types of uranium reference powder was prepared, and the uranium particles in test sample were isolated using the micromanipulation technique under scanning electron microscopy conditions. APM results without and with micromanipulation were compared in terms of accuracy of the APM results and the determination of the existence of minor uranium isotopes. Comparison between APM without and with micromanipulation showed the results of APM with micromanipulation were more accurate by reducing the number of inaccurate data, such as those detected from the particle mixing effect, from 31% to 3.6%. APM combined with micromanipulation was also able to determine the existence of minor uranium isotopes in test samples.