Diamond-like carbon coatings for Ultracold Neutron applications

Diamond-like carbon (DLC) is a promising new wall coating material for use in applications with Ultracold Neutrons (UCN). It can potentially replace the toxic beryllium which has been widely used for the storage and transport of UCN.Our aim is to produce DLC-coated neutron guide tubes of up to 1.2 m length with a Pulsed Laser Deposition (PLD) setup which is currently under construction. In order to find optimal process parameters and appropriate settings for the tube coating facility, we are carrying out a research program which includes the production and characterization of DLC films on small test samples.The characterization of the test samples is done by Raman spectroscopy, X-ray Photoelectron Spectroscopy (XPS) and Neutron Reflectometry. We report on first results from the test samples with sp3 fractions up to 55% and give an overview of the tube coating setup.