| 摘要 |
PURPOSE:To prevent the deterioration of the mutual conductance of an MOSFET due to an offset by attaching an insulating film having an impurity reverse to an Si substrate to the side wall of a gate electrode and diffusing the impurity to the Si substrate from the insulating film. CONSTITUTION:A field oxide film 2 is formed to an N type Si substrate 1. A gate oxide film 3 and polycrystalline silicon 4 to which phosphorus is doped are grown, thus forming a gate electrode. An SiO2 film 11 to which boron is doped is shaped. The thickness of the gate electrode is proper as film thickness. The SiO2 film 11 is etched by reactive ions so as to remain on the side wall of the gate electrode, and a high melting-point metal 6 is attached and silicified 7. An SiO2 8 to which phosphorus is doped is formed, and thermally treated at 900 deg.C in an N2 atmosphere with the object of compacting. The mutual conductance of an MOSFET is not deteriorated because boron is diffused to the Si substrate 1 from the SiO2 film 11 through the heat treatment and impurity layers 12 are shaped. |
