Preparation and characterisation of thin film nuclear targets for neutron physical measurements

In the target preparation laboratory of the Institute for Reference Materials and Measurements, lithium fluoride, boron, and tristearin thin films are produced by physical vapour deposition for neutron spectroscopy experiments and for neutron cross-section measurements. In all of these applications the accuracy of the obtained measurements greatly depends on the properties of the deposited films and the characterisation of the areal density. In this work we describe the production of various nuclear targets. The characterisation methods depend on the nature of the particular film/substrate system. Different characterisation techniques and the uncertainties in the determined areal densities necessary for neutron physical calculations are presented and compared.