Search for radiation-induced electrical degradation in ion irradiated sapphire and polycrystalline Al2O3

An international discussion is being carried out on whether radiation-induced electrical degradation in ceramic insulators does or does not exist. In the present experiments on radiation-induced conductivity and radiation-induced electrical degradation in high purity polycrystalline Al2O3 and sapphire all interfering effects resulting from surface conductances have been eliminated. The results have not confirmed a permanent degradation of the volume conductivity. Radiation-induced conductivity values were observed to decrease with dose. A transient in the electrical conductivity after ion beam off was discovered. (C) 1999 American Institute of Physics. [S0021-8979(99)05702-3].