[en] Measurement and analysis were made for radiation damages in silicon induced by MeV ions. A single crystal silicon was bombarded by 800 keV O⁺ and 700 keV Si⁺ with the dose from 2x10¹⁵ up to 8x10¹⁵ cm^-2. And defects induced by the ion bombardments were observed by the channeling method. Some new modifications were made to the analysis of the channeling RBS spectrum so that the accuracy of the unfolded defect distribution may be improved. A new model of point-defect clustering and amorphous formation was proposed, which well reproduced the observed defect distribution in silicon. (author)