Investigation of the scintillation screens used for low energy DC ion beam profiling

A ion beam profile monitoring system based on scintillation screens has been established for a neutron generator used for neutron radiography. Three types of scintillation screens (monocrystalline Al2O3, Quartz and BGO) were investigated for their response to the 100 keV, 30 μA, DC deuterium ion beams. The light yield, beam width, and electric charge accumulation effect of the scintillation materials were tested. The temperature rises of the scintillation screens caused by ion irradiation was calculated. Results showed that, the electric charge accumulation effect is very serious for this type of ion beams, and the using of metal film or mesh on the scintillation screen surface to diminish the electric charging is necessary. Al2O3 screen owns the best behavior of radiation hardness, its measured beam width only shows a little change for the ion irradiation of up to 2.3×1015 particles/mm2. The temperature rises of Al2O3, Quartz and BGO under ion irradiation of 2.3×1015 particles/mm2 was 120°C, 243°C, and 768°C respectively. The temperature rise difference is quite coincident with the light yield degradation of the three material, so temperature might be the key factor that affect the light yield degradation of scintillation materials.