| 摘要 |
PURPOSE:To hold generation of step differences on the surface of a substrate and crystal defects at the minimum limit by a method wherein poly-Si surrounded with a thin SiO2 film is buried in an element isolation region. CONSTITUTION:Ion etching is performed to the N type Si substrate 4 to provide a perpendicular groove, and the thin SiO2 film 5 is formed. Generation of the crystal defects is held at the minimum limit because thickness of the film is not necessitated. Then the extremely narrow groove is filled up with poly-Si 6 according to the CVD method, and poly-Si 6 on the surface is etched to be removed to leave poly-Si 6 in the groove. N ions are implanted in high concentration in poly-Si 6 in succession using an Si3N4 mask, and the mask is removed to complete. By this constitution, the step differences on the surface of the substrate and the crystal defects can be held at the minimum limit. |
