Properties of the photodiode PiN as neutron detector

The photodiode can be used to measure the ambient dose equivalent for an Am-Be source, as well placed in a paraffin sphere with LiF6 converter as nude with a PE converter. The ratio between the counting rate and the ambient dose equivalent is linear in the two cases. The sensitivity of the diode with the converter 6LiF is evaluated to 8.4 shocks by micro sievert by square centimeter of active surface of diode. The photodiode with the PE converter has a sensitivity lower of 2.1 shocks by micro sievert by square centimeter (for the Am-Be source) of active surface of diode. About the disadvantages, the disadvantage of photodiode inside the paraffin sphere is its size and weight; the disadvantage of the diode with the PE converter is its sensitivity to the orientation of the neutron flux and the necessity to calibrate for the source type. (N.C.)