Study on secondary electron suppression in compact D–D neutron generator

Structural and Secondary Electron Yield Properties of Titanium–Palladium Films with Laser-Treated Copper Substrate for Application in Neutron Generators

“…Besides, the ion beam instability in the vacuum chamber of neutron generators is another problem that cannot be ignored when the neutron yield is increased. Beam instability is mainly induced by the secondary electron emission on the target, which affects the operation stability of the neutron generator, and poses a potential safety hazard [ 16 ]. In this case, characterizing these neutron generators is essential for improving their functionality.…”

“…The neutron generator is mainly composed of an ion source, an ion extraction–accelerating system, a target system, and a vacuum system [ 16 , 17 ]. Generally, deuterium ions are produced in the ion source, then extracted and accelerated by the extraction–accelerating electrode.…”

“…Due to the voltage difference, secondary electrons (SEs) are produced inevitably from the target surface when bombarded by the high-energy deuterium ion beam, and then accelerated back to the vacuum, as well as the ion source. This results in the formation of the secondary electron current, an increase in power loads, and the unstable operation of the neutron generator [ 16 , 18 , 19 ]. To reduce the secondary electron yield (SEY) in neutron generators, various methods of secondary electron suppression have been developed, such as Faraday cup suppression, magnetic and electric field suppression, and combinations of these methods [ 16 , 20 ].…”

“…This results in the formation of the secondary electron current, an increase in power loads, and the unstable operation of the neutron generator [ 16 , 18 , 19 ]. To reduce the secondary electron yield (SEY) in neutron generators, various methods of secondary electron suppression have been developed, such as Faraday cup suppression, magnetic and electric field suppression, and combinations of these methods [ 16 , 20 ]. However, the disadvantages are that they introduce extra components and occupy the neutron generation space.…”

“…For the electric field suppression method, a resistor connecting the extraction–accelerating electrode to the target is applied to provide a bias voltage during the D+ ion bombardment. Secondary electrons can be completely suppressed with high resistance [ 16 ]. Different neutron generator structures require different bias voltages.…”