Device Degrdation from the Effects of Nuclear Radiation on Passivation Materials

Devices that utilized three different commercial passivation processes were studied in a nuclear radiation environment to determine if the passivation process influences the radiation tolerance of the device. Comparisons were made between devices obtained from the same manufacturer. The passivation processes studied featured silicon dixoide, silicon nitride and aluminum oxide. Irradiations were performed with the devices in both a biased and unbiased mode. The results show that the device with silicon dioxide passivation degraded the most. The nitride devices having beam leads showed no saturation of the induced degradation while the other processes did for a dose of 1 × 107 (Si). All devices studied showed a small bias dependence. The addition of an aluminum oxide or silicon nitride passivation layer (over the silicon dioxide surface) for an increased reliability definitely induces no increased radiation degradation.