Most neutron detection systems at spallation sources are based on 3Hedetectors that have an excellent intrinsic efficiency (>70% for thermal neutrons) andcan cover large areas (several m2). Nevertheless the production of 3He from tritiumdecay has declined as the nuclear weapons stockpile has been reduced. This has led toa substantial increase of the 3Heprice preventing its extensive use for researchapplications including future neutron sources such as the European Spallation Source(ESS). Besides the need for replacing 3He,it is essential to develop high-rate neutrondetectors that can fully exploit the increase of neutron flux of ESS compared topresent-day sources. Thus, it is necessary to develop a large area and high-rateneutron detector that does not use 3Hebut has a comparable detection efficiency, anaffordable price and a space resolution of 1-100 mm.