Observation of surface roughness at the interface by neutron reflectometry

The surface roughness of Fe-blocks, manufactured by mechanical grinding, has been observed by neutron reflectometry in air and at the interface with a Si-block. A reflectometer, MINE, at JRR-3 in JAEA was used. Fe-blocks having various types of surface roughness were prepared with roughnesses, R-max of 0-1-0.8 mu m. The beam distribution observed by an imaging plate (IP) was compared with the intensity distribution estimated from the surface roughness measured by a contact-type roughness gauge. The intensity distribution observed on the IP agrees well with the calculated intensity distribution and becomes more dispersive with increasing roughness. Neutron reflectometry was found to be very useful for observing the mechanical surface roughness with an accuracy of 0.1 mu m, especially at the solid-solid interface. (c) 2006 Elsevier B.V. All rights reserved.