Various deposits of CdO grains were observed on the surface of N 100 silicon crystals heated at 580 °C and 620 °C for 1 hour in an evaporation-deposition device, respectively. The ball-shaped crystals, and regular-prism-shaped crystals were found on top of bush-like long crystals. Two types of CdO self-organization aggregates were also observed, that is, regular circular-shaped dense aggregate and long-chainshaped aggregate. The self-organization aggregates were composed of numerous submicron CdO grains. The relationship between self-organization aggregates and surface defects of virgin N 100 silicon crystal was investigated. The results showed that the CdO self-organization aggregates were related to surface defects of the virgin N 100 silicon crystal, and a defect induced aggregation (DIA) model is suggested.