| 摘要 |
PURPOSE:To form a defect-free region on the surface of a silicon substrate by executing gettering of microscopic defect and heavy metal, by conducting high-temperature and low-temperature heat treatments after injecting oxygen ions into a semiconductor substrate. CONSTITUTION:Oxygen ions 2 are injected into an entire surface of a silicon substrate 1, and a high-density injection region 3 is formed in the substrate. And then, by conducting high-temperature heat treatment in inert gas atmosphere, oxygen atoms are precipitated in the neighborhood of the peak of the injected oxygen density distribution and a layer 4 of precipitant of SiO2 is formed. By this high-temperature heat treatment, defect in the ion injecting layer is removed and a layer 5 of a low oxygen density and less defect is formed. And then, the silicon substrate is oxidized in dry oxygen atmosphere, microscopic defects composed of oxygen precipitants, etc. of the region 4 are made to grow, and by effects of intrinsic gettering, the region 5 is turned into a defect-free region. |
