Evaluation of commercial silicon diode for electron dosimetry

Ionization chambers have been widely used as the reference detector for measurements of photon and electron beams. However, advances in silicon planar technology have allowed the use of silicon diodes in spectrometry and dosimetry of radiations. The aim of this study is to evaluate the response of a PIN silicon diode for electron dosimetry. The diode selected for this study is a planar-processed silicon diode XRA-50. Its active area is 25 mm2 and it is characterized by a low leakage current and a low terminal capacitance of 14 pF for reverse voltage of 30 V. The results showed a linear dose response of the diode for 4, 9, and 15 MV electron beam energies, with a determined coefficient of 0.99997. The results of the depth dose curves measured with the diode showed a good agreement with the ones obtained with the ionization chamber. The difference is lower than 2%. These results demonstrate that the XRA-50 is suitable for electron dosimetry.