Fast neutron radiation effects in siicon detectors fabricated by different thermal oxidation processes

This paper reports on high resistivity silicon detectors along with MOS capacitors made on five silicon dioxides with different thermal conditions (975 degrees C to 1200 degrees C) that have been exposed to fast neutron irradiation up to the fluence of a few times 1014 n/cm2. New measurement techniques such as capacitance-voltage (C-V) of MOS capacitors and current-voltage (I-V) of back to back diodes (p+-n--p+ if n- is not inverted to;) or resistors (p+-p-+ if inverted) have been introduced in this study in monitoring the possible type-inversion (n → p) under high neutron fluence. No type-inversion in the material underneath SiO2 and the p+ contact has been observed so far in this work for detectors made on the five oxides up to the neutron fluence of a few times 1013 n/cm2. However, it has been found that detectors made on higher temperature oxides (T ≥ 1100 degrees C) exhibit less leakage current increase at high neutron fluence (φ ≥ 1013 n/cm2)