Serious degradation of the optical and electrical properties of Al₂O₃ is concerned under the irradiation environment due to energetic particles. Also, it is pointed out that the intrinsic impurities and transmutation products such as hydrogen in the ceramics influence defect formation.  In the present study, damage evolution and hydrogen behavior under the H and He ion irradiation was examined by using the ion beam analysis techniques and luminescence measurements.

Single crystals of Al₂O₃ were irradiated by H and He ions with 5 ~ 200 keV up to a fluence of 2 x 10¹⁸ cm^-2.   Rutherford Backscattering Spectroscopy combined with channeling technique (RBS/C) was employed to investigate the evolution and thermal annealing of ion-induced damages.    The concentration depth profiles of retained H and He were measured by the Elastic Recoil Detection Analysis.     The ion- and photo- stimulated luminescence were also detected during the ion irradiation.   The depth distribution of the displaced atoms by D ions extended to the depth far beyond the projected ranges of incident D ions, coinciding with retained D distribution, while He ion-induced defects has a similar profile to calculation.   The formation rate of the Al displacements was considerably lower than that of the O displacements at small fluence below 2 x 10¹⁶ cm^-2 for D ions.   Luminescence measurements showed the formation of F⁺ and F₂ type bands and annihilation of F and Cr³⁺ bands during the ion irradiation.    The F⁺ bands were more effectively created by the D ion irradiation, in comparison with He irradiation.