Research on silicon PIN neutron dose detector

Two batches of Si PIN diodes, with different area, are fabricated. The silicon resistivity is 2k Omega.cm and 20k Omega.cm respectively for the two batches. The response of the diodes to Pu-239-Be isotopic neutron source, whose average energy is similar to 4.5 MeV, is measured. The change of the forward I-V curve after radiation is studied. The experimental results indicate that the diode with high resistivity biased at high level injection is more sensitive to the neutron radiation. It is also shown that, the sensitivity increases as the geometry size increases at low neutron dose, but decreases when the neutron dose gets high enough.