Si PIN diodes for detecting topsoil contamination

In some environmental cleanup applications, there is a need for utilizing Si PIN diodes to detect electrons, x-rays, and low-energy gamma rays with very good energy resolution. The advantage of these detectors in such particular applications when compared with others is the ease of the operation at room temperature and at much lower bias voltages. We are currently investigating the feasibility of using silicon PIN photodiodes to detect the x-rays of radioisotopes such as Cs, Eu, La, U, Th, Am, and Pu for monitoring and characterizing topsoil contamination. The design and development of this Si PIN diode array will be discussed and the results of tests and its overall performance will be presented.