Radiation-induced conductivity of doped silicon in response to photon, proton and neutron irradiation

The opto-electronic performance of semiconductors during reactor operation is restricted by radiation-induced conductivity (RIC) and the synergistic e ffects of neutrons/ions and photons. The RICs of Si due to photons, protons and pulsed neutrons have been evaluated, aiming at radiation correlation. Protons of 17 MeV with an ionizing dose rate of 10(3) Gy/s and/or photons ( hv = 1.3 eV) were used to irradiate impurity-doped Si (2 x 10(16) B atoms/c m(3)) at 300 and 200 K. Proton-induced RIC (p-RIC) and photoconductivity (P C) were intermittently detected in an accelerator device. Neutron-induced R IC (n-RIC) was measured for the same Si in a pulsed fast-fission reactor, B ARS-6, with a 70-mus pulse of 2 x 10(12) n/cm(2) (E > 0.01 MeV) and a dose rate of up to 6 x 10(5) Gy/s. The neutron irradiation showed a saturation t endency in the flux dependence at 300 K due to the strong electronic excita tion. Normalization of the electronic excitation, including the pulsed regi me, gave a fair agreement among the different radiation environments. Detai led comparison among PC, p-RIC and n-RIC is discussed in terms of radiation correlation including the in-pile condition. (C) 2000 Elsevier Science B.V . All rights reserved.