  Nowadays neutron facilities are going toward higher fluxes, e.g. the European
Spallation Source (ESS) in Lund (Sweden), and this translates into a higher
demand in the instrument performances. Because of its favorable properties,He-3
has been the main actor in thermal neutron detection for years. Starting in
about 2001 the He-3 stockpile has been declining. The world is now experiencing
the shortage of He-3. This makes the construction of large area detectors
(several squared meters) not realistic anymore. A way to reduce the He-3 demand
for those applications is to move users to alternative technologies, such as
Boron-10. Although it is absolutely necessary to replace He-3 for large area
applications, this is not the main issue for what concerns small area detectors
for which the research is focused on improving their performances. Some
technologies appear promising, though implementation would likely present
technical challenges. There are several aspects that must be investigated in
order to validate those new technologies; e.g. detection efficiency and
gamma-ray sensitivity. Several detectors, based on Boron-10 layers, have been
conceived, built and tested. We have laid a solid theoretical basis, confirmed
by experiments, for the understanding of the main aspects of solid converter
layers employed in neutron detectors. We also explored practically, by the
construction and characterization of prototypes, a specific type of
solid-converter-based neutron detector, the Multi-Blade, especially suited for
application in neutron reflectometry.
