The ceramic-cup microwave ion source for sealed-tube neutron generator

A microwave proton source for sealed-tube neutron generator has been built in the radiation Technology Institute of Northeast Normal University. The plasma resonance chamber is made of 95%Al2O3 ceramic material. The microwave absorption as a function of the magnetic field and the pressure is studied. The microwave absorption efficiencies, (P-i-P-r)/P-i are more than 90% when the magnetic field at the microwave windows is 0.095 T and incident microwave power is 300-500 W, at the same time, the impedance between the microwave circuit and the plasma source is well matched. Two-grid multi-hole extraction electrodes are employed to extract ion. The maximum proton current of 30 mA is obtained when the extraction voltage is 5.4 KV and the incident microwave power is 300 W. (C) 2001 American Institute of Physics.